CMTXX Cma Treasury Fund (MM)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM N-CSRS CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number 811-06196 and 811-21298 Name of Fund: CMA Treasury Fund and Master Treasury LLC Fund Address: 100 Bellevue Parkway, Wilmington, DE 19809 Name and address of agent for service: Donald C. Burke, Chief Executive Officer, CMA Treasury Fund and Master Treasury LLC, 800 Scudders Mill Road, Plainsboro, NJ, 08536. Mailing address: P.O. Box 9011, Princeton, NJ, 08543-9011 Registrant’s telephone number, including area code: (800) 221-7210 Date of fiscal year end: 03/31/2009 Date of reporting period: 04/01/2008 – 09/30/2008 Item 1 – Report to Stockholders

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Semi-Annual Report (Unaudited) September 30, 2008

CMA Government Securities Fund CMA Treasury Fund

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Table of Contents
		Page
A Letter to Shareholders		3
Semi-Annual Report:
Disclosure of Expenses		4
Current Seven-Day Yield		4
Fund Financial Statements:
Statements of Assets and Liabilities		5
Statements of Operations		6
Statements of Changes in Net Assets		7
Fund Financial Highlights		8
Fund Notes to Financial Statements		10
Master LLC Portfolio Summary		12
Master LLC Financial Statements:
Schedules of Investments		13
Statements of Assets and Liabilities		16
Statements of Operations		17
Statements of Changes in Net Assets		18
Master LLC Financial Highlights		19
Master LLC Notes to Financial Statements		20
Disclosure of Investment Advisory Agreement and Subadvisory Agreement		22
Officers and Directors		26
Additional Information		27

2 SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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A Letter to Shareholders

Dear Shareholder

It has been a tumultuous period for investors, marked by almost daily headlines related to the housing market turmoil, volatile energy prices, and the escalating credit crisis. The news took an extraordinarily heavy tone in September as the credit crisis boiled over and triggered unprecedented failures and consolidation in the financial sector, stoking fears of a market and economic collapse and prompting the largest government rescue plan since the Great Depression.

Through it all, the Federal Reserve Board (the “Fed”) has taken decisive action to restore liquidity and bolster financial market stability. Key moves included slashing the target federal funds rate 275 basis points (2.75%) between October 2007 and April 2008 and providing massive cash injections and lending programs. As the credit crisis took an extreme turn for the worse, the Fed, in concert with five other global central banks, cut interest rates by 50 basis points in early October in a rare move intended to stave off worldwide economic damage from the intensifying financial market turmoil. The U.S. economy managed to grow at a slow-but-positive pace through the second quarter of the year, though recent events almost certainly portend a global economic recession.

Against this backdrop, U.S. stocks experienced intense volatility and generally posted losses for the current reporting period, with small-cap stocks faring noticeably better than their larger counterparts. Non-U.S. markets followed the U.S. on the way down and, notably, decelerated at a faster pace than domestic equities — a stark reversal of recent years’ trends, when international stocks generally outpaced U.S. stocks.

Treasury securities also traded in a volatile fashion, but rallied overall (yields fell and prices correspondingly rose) amid an ongoing flight to quality. The yield on 10-year Treasury issues, which fell to 3.34% in March, climbed to the 4.20% range in mid-June as investors temporarily shifted out of Treasury issues in favor of riskier assets (such as stocks and other high-quality fixed income sectors), then declined again to 3.85% by period-end as the financial market contagion widened. Tax-exempt issues underperformed overall, as problems among municipal bond insurers and the collapse in the market for auction rate securities pressured the group throughout the course of the past year. At the same time, the above mentioned economic headwinds and malfunctioning credit markets led to considerable weakness in the high yield sector.

Facing unprecedented volatility and macro pressures, the major benchmark indexes generally recorded losses over the six- and 12-month reporting periods:

Total Returns as of September 30, 2008		6-month		12-month
U.S. equities (S&P 500 Index)		(10.87)%		(21.98)%
Small cap U.S. equities (Russell 2000 Index)		(0.54)		(14.48)
International equities (MSCI Europe, Australasia, Far East Index)		(22.35)		(30.50)
Fixed income (Barclays Capital U.S. Aggregate Index)*		(1.50)		3.65
Tax-exempt fixed income (Barclays Capital Municipal Bond Index)*		(2.59)		(1.87)
High yield bonds (Barclays Capital U.S. Corporate High Yield 2% Issuer Capped Index)*		(6.77)		(10.51)

*	Formerly a Lehman Brothers index.
	Past performance is no guarantee of future results. Index performance shown for illustrative purposes only. You cannot invest directly in an index.

Through periods of market turbulence, as ever, BlackRock’s full resources are dedicated to the management of our clients’ assets. For our most current views on the economy and financial markets, we invite you to visit www.blackrock.com/funds . As always, we thank you for entrusting BlackRock with your investments, and we look forward to continuing to serve you in the months and years ahead.

Sincerely,

Rob Kapito President, BlackRock Advisors, LLC

THIS PAGE NOT PART OF YOUR FUND REPORT

3

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Disclosure of Expenses Shareholders of the Funds may incur the following charges: (a) expenses related to transactions, including sales charges, redemption fees and exchange fees; and (b) operating expenses including advisory fees, distri- bution fees including 12b-1 fees, and other Fund expenses. The expense example below (which is based on a hypothetical investment of $1,000 invested on April 1, 2008 and held through September 30, 2008) is intended to assist shareholders both in calculating expenses based on an investment in the Funds and in comparing these expenses with similar costs of investing in other mutual funds. The table below provides information about actual account values and actual expenses. In order to estimate the expenses a shareholder paid during the period covered by this report, shareholders can divide their account value by $1,000 and then multiply the result by the number in the first line under the heading entitled “Expenses Paid During the Period.”

The table also provides information about hypothetical account values and hypothetical expenses based on the Funds’ actual expense ratio and an assumed rate of return of 5% per year before expenses. In order to assist shareholders in comparing the ongoing expenses of investing in these Funds and other funds, compare the 5% hypothetical example with the 5% hypothetical examples that appear in other funds’ shareholder reports. The expenses shown in the table are intended to highlight shareholders’ ongoing costs only and do not reflect any transactional expenses, such as sales charges, redemption fees or exchange fees. Therefore, the hypothetical example is useful in comparing ongoing expenses only, and will not help shareholders determine the relative total expenses of owning different funds. If these transactional expenses were included, shareholder expenses would have been higher.

Expense Example

Actual

Hypothetical 1

Beginning

Ending

Beginning

Ending

Account Value

Account Value

Expenses Paid

Account Value

Account Value

Expenses Paid

April 1, 2008

September 30, 2008

During the Period

April 1, 2008

September 30, 2008

During the Period

CMA Government Securities Fund

$1,000

$1,006.40

$3.21 2

$1,000

$1,021.80

$3.23 2

CMA Treasury Fund

$1,000

$1,005.70

$2.81 3

$1,000

$1,022.20

$2.83 3

1 Hypothetical 5% annual return before expenses is calculated by pro-rating the number of days in the most recent fiscal half year divided by 365. 2 Expenses are equal to the Fund’s annualized expense ratio of 0.64%, multiplied by the average account value over the period, multiplied by 183/366 (to reflect the one-half year period shown). Because the Fund is a feeder fund, the expense table example reflects the expenses of both the feeder fund and the master fund in which it invests. 3 Expenses are equal to the Fund’s annualized expense ratio of 0.56%, multiplied by the average account value over the period, multiplied by 183/365 (to reflect the one-half year period shown). Because the Fund is a feeder fund, the expense table example reflects the expenses of both the feeder fund and the master fund in which it invests.

Current Seven-Day Yield
As of September 30, 2008
CMA Government Securities Fund		0.81%
CMA Treasury Fund		0.44%

4 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Statements of Assets and Liabilities
		CMA		CMA
		Government		Treasury
September 30, 2008 (Unaudited)		Securities Fund		Fund
Assets
Investments at value — Master Government LLC and Master Treasury LLC (individually “Government LLC”
and “Treasury LLC”, or collectively, the “Master LLCs”), respectively 1		$ 794,239,216		$ 4,823,085,749
Capital shares sold receivable		5,677		—
Withdrawals receivable from Master LLCs		—		20
Prepaid expenses		34,278		45,704
Other assets		27,362		1,022
Total assets		794,306,533		4,823,132,495
Liabilities
Administration fees payable		139,954		601,810
Distribution fees payable		91,377		368,327
Other affiliates payable		4,911		20,766
Contributions payable to Master LLCs		5,677		—
Officer’s and Director’s fees payable		55		155
Capital shares redeemed payable		—		20
Other accrued expenses payable		—		41,196
Other liabilities		6,696		—
Total liabilities		248,670		1,032,274
Net Assets		$ 794,057,863		$ 4,822,100,221
Net Assets Consist of
Par value $0.10 per share, unlimited number of shares authorized 2		$ 79,400,938		$ 482,202,016
Paid-in capital in excess of par		714,608,438		4,339,818,144
Accumulated net realized gain allocated from the Master LLCs		48,487		80,061
Net Assets , $1.00 net asset value per share		$ 794,057,863		$ 4,822,100,221
1 Investments at cost — affiliated		$ 794,239,216		$ 4,823,085,749
2 Shares issued and outstanding		794,009,378		4,822,020,162

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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Statements of Operations
		CMA		CMA
		Government		Treasury
Six Months Ended September 30, 2008 (Unaudited)		Securities Fund		Fund
Investment Income
Income from affiliates		$ 4,219		$ 414
Net investment income allocated from the Master LLCs:
Interest		6,576,996		18,184,501
Expenses		(798,129)		(1,882,540)
Total income		5,783,086		16,302,375
Expenses
Administration		866,258		2,764,377
Distribution		429,737		1,369,830
Registration		45,560		55,091
Transfer agent		31,940		60,089
Printing		18,126		19,902
Professional		12,391		13,838
Officer and Directors		307		644
Miscellaneous		5,462		4,803
Total expenses		1,409,781		4,288,574
Net investment income		4,373,305		12,013,801
Realized Gain Allocated from the Master LLCs
Net realized gain from investments		6,962		987
Net Increase in Net Assets Resulting from Operations		$ 4,380,267		$ 12,014,788

See Notes to Financial Statements.

6 SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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Statements of Changes in Net Assets
		CMA				CMA
		Government				Treasury
		Securities Fund				Fund
		Six Months Ended				Six Months Ended
		September 30,		Year Ended		September 30,		Year Ended
		2008		March 31,		2008		March 31,
Increase (Decrease) in Net Assets:		(Unaudited)		2008		(Unaudited)		2008
Operations
Net investment income		$ 4,373,305		$ 20,585,647		$ 12,013,801		$ 26,305,383
Net realized gain		6,962		40,333		987		75,736
Net change in unrealized appreciation/depreciation		—		(317,367)		—		(237,480)
Net increase in net assets resulting from operations		4,380,267		20,308,613		12,014,788		26,143,639
Dividends to Shareholders From
Net investment income		(4,373,305)		(20,585,647)		(12,013,801)		(26,305,383)
Capital Share Transactions
Net proceeds from sale of shares		1,751,146,674		3,558,225,628		8,171,605,679		6,787,124,671
Reinvestment of dividends		4,373,305		20,585,274		12,013,801		26,305,383
Cost of shares redeemed		(1,759,272,230)		(3,283,891,056)		(5,796,103,477)		(4,841,539,372)
Net increase (decrease) in net assets derived from share transactions		(3,752,251)		294,919,846		2,387,516,003		1,971,890,682
Net Assets
Total increase (decrease) in net assets		(3,745,289)		294,642,812		2,387,516,990		1,971,728,938
Beginning of period		797,803,152		503,160,340		2,434,583,231		462,854,293
End of period		$ 794,057,863		$ 797,803,152		$4,822,100,221		$2,434,583,231

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

7

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Financial Highlights								CMA Government Securities Fund
		Six Months Ended
		September 30,
		2008				Year Ended March 31,
		(Unaudited)		2008		2007		2006				2005		2004
Per Share Operating Performance
Net asset value, beginning of period		$ 1.00		$ 1.00		$ 1.00		$ 1.00		$ 1.00				$ 1.00
Net investment income		0.0064		0.0369		0.0439		0.0291				0.0102		0.0053
Net realized and unrealized gain (loss)		0.0000 1		(0.0005)		0.0003		0.0001				(0.0010)		(0.0003)
Net increase from investment operations		0.0064		0.0364		0.0442		0.0292				0.0092		0.0050
Dividends and distributions from:
Net investment income		(0.0064)		(0.0369)		(0.0439)		(0.0291)				(0.0102)		(0.0053)
Net realized gain		—		(0.0000) 2		(0.0000) 2		(0.0000) 2				(0.0000) 2		(0.0001)
Total dividends and distributions		(0.0064)		(0.0369)		(0.0439)		(0.0291)				(0.0102)		(0.0054)
Net asset value, end of period		$ 1.00		$ 1.00		$ 1.00		$ 1.00		$ 1.00				$ 1.00
Total Investment Return
Total investment return		0.64% 3		3.74%		4.46%		2.96%				1.03%		0.52%
Ratios to Average Net Assets 4
Total expenses		0.64% 5		0.66%		0.70%		0.67%				0.66%		0.63%
Net investment income		1.26% 5		3.53%		4.41%		2.89%				0.98%		0.56%
Supplemental Data
Net assets, end of period (000)		$ 794,058		$ 797,803		$ 503,160		$ 467,534		$ 525,113				$ 652,654

1	Amount is less than $0.0001 per share.
2	Amount is less than $(0.0001) per share.
3	Aggregate total investment return.
4	Includes the Fund’s share of the Government LLC’s allocated expenses and/or net investment income.
5	Annualized.

See Notes to Financial Statements.

8 SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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Financial Highlights (concluded)							CMA Treasury Fund
		Six Months Ended
		September 30,		Year Ended March 31,
		2008
		(Unaudited)		2008	2007	2006	2005	2004
Per Share Operating Performance
Net asset value, beginning of period		$ 1.00		$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Net investment income		0.0056		0.0343	0.0421	0.0277	0.0094	0.0040
Net realized and unrealized gain (loss)		0.0000 1		(0.0002)	0.0003	0.0001	(0.0004)	(0.0001)
Net increase from investment operations		0.0056		0.0341	0.0424	0.0278	0.0090	0.0039
Dividends and distributions from:
Net investment income		(0.0056)		(0.0343)	(0.0421)	(0.0277)	(0.0094)	(0.0040)
Net realized gain		—		—	(0.0000) 2	(0.0001)	(0.0000) 2	(0.0001)
Total dividends and distributions		(0.0056)		(0.0343)	(0.0421)	(0.0278)	(0.0094)	(0.0041)
Net asset value, end of period		$ 1.00		$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Total Investment Return
Total investment return		0.57% 3		3.48%	4.28%	2.81%	0.95%	0.41%
Ratios to Average Net Assets 4
Total expenses		0.56% 5		0.60%	0.68%	0.67%	0.66%	0.63%
Net investment income		1.09% 5		2.92%	4.22%	2.76%	0.94%	0.43%
Supplemental Data
Net assets, end of period (000)		$ 4,822,100		$ 2,434,583	$ 462,854	$ 481,630	$ 602,207	$ 673,375

1	Amount is less than $0.0001 per share.
2	Amount is less than $(0.0001) per share.
3	Aggregate total investment return.
4	Includes the Fund’s share of the Treasury LLC’s allocated expenses and/or net investment income.
5	Annualized.

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

9

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Notes to Financial Statements (Unaudited) CMA Government Securities Fund and CMA Treasury Fund

1. Significant Accounting Policies:

CMA Government Securities Fund and CMA Treasury Fund (the “Funds” or
individually the “Fund”) are registered under the Investment Company Act
of 1940, as amended (the “1940 Act”), as no load, diversified, open-
end management investment companies. CMA Government Securities
Fund and CMA Treasury Fund seek to achieve their investment objectives
by investing all of their assets in Master Government Securities LLC and
Master Treasury LLC (individually “Government LLC” and “Treasury LLC,”
or collectively the “Master LLCs”), respectively, each of which has the
same investment objective and strategies as the related Fund. The value
of each Fund’s investment in the related Master LLC reflects each Fund’s
proportionate interest in the net assets of the respective Master LLC.
The performance of each Fund is directly affected by the performance
of the related Master LLC. The financial statements of the Master LLCs,
including the Schedules of Investments, are included elsewhere in this
report and should be read in conjunction with the Funds’ financial state-
ments. The Funds’ financial statements are prepared in conformity with
accounting principles generally accepted in the United States of America,
which may require the use of management accruals and estimates.
Actual results may differ from these estimates. The percentages of the
Government LLC and Treasury LLC owned by CMA Government Securities
Fund and CMA Treasury Fund at September 30, 2008 were 60.8% and
75.5%, respectively.

The following is a summary of significant accounting policies followed
by the Funds:

Valuation of Investments: The Funds record their investment in the appli-
cable Master LLC at fair value. Valuation of securities held by the Master
LLCs is discussed in Note 1 of the Master LLCs’ Notes to Financial
Statements, which are included elsewhere in this report. The Funds seek
to maintain the net asset value per share at $1.00, although there is no
assurance that it will be able to do so on a continuing basis.

Effective April 1, 2008, each Fund adopted Financial Accounting
Standards Board Statement of Financial Accounting Standards No. 157,
"Fair Value Measurements" ("FAS 157"). FAS 157 clarifies the definition
of fair value, establishes a framework for measuring fair values and
requires additional disclosures about the use of fair value measure-
ments. Various inputs are used in determining the fair value of invest-
ments, which are as follows:

_{• Level 1 — price quotations in active markets/exchanges for}
identical securities

_{• Level 2 — other observable inputs (including, but not limited to:}
quoted prices for similar assets or liabilities in markets that are not
active, inputs other than quoted prices that are observable for the
assets or liabilities (such as interest rates, yield curves, volatilities,
prepayment speeds, loss severities, credit risks, and default rates)
or other market-corroborated inputs)

_{• Level 3 — unobservable inputs based on the best information avail-}
able in the circumstance, to the extent observable inputs are not
available (including the Funds’ own assumption used in determining
the fair value of investments)

The following table summarizes the inputs used as of September 30,
2008 in determining the fair valuation of each Fund’s investments:

		Investments in Securities
		CMA
		Government		CMA
		Securities		Treasury
Valuation Inputs		Fund		Fund
Level 1		—		—
Level 2		$ 794,239,216		$4,823,085,749
Level 3		—		—
Total		$ 794,239,216		$4,823,085,749

Investment Transactions and Net Investment Income: Investment trans-
actions in the Master LLCs are accounted for on a trade date basis. The
Funds record daily their proportionate share of the related Master LLC’s
income, expenses and realized gains and losses. In addition, the Funds
accrue their own income and expenses.

Dividends and Distributions to Shareholders: Dividends from net
investment income are declared and reinvested daily and paid
monthly. Distributions of realized gains, if any, are recorded on the
ex-dividend dates.

Income Taxes: It is each Fund’s policy to comply with the requirements
of the Internal Revenue Code applicable to regulated investment compa-
nies and to distribute substantially all of its taxable income to its share-
holders. Therefore, no federal income tax provision is required.

The Funds file U.S. federal and various state and local tax returns.
No income tax returns are currently under examination. The statute of
limitations on the Funds’ U.S. federal tax returns remains open for the
years ended March 31, 2005 through March 31, 2007. The statute of
limitations on the Funds’ state and local tax returns may remain open
for an additional year depending upon the jurisdiction.

Recent Accounting Pronouncement: In March 2008, Statement of
Financial Accounting Standards No. 161, "Disclosures about Derivative
Instruments and Hedging Activities — an amendment of FASB Statement
No. 133" ("FAS 161"), was issued. FAS 161 is intended to improve
financial reporting for derivative instruments by requiring enhanced
disclosure that enables investors to understand how and why an entity
uses derivatives, how derivatives are accounted for, and how derivative
instruments affect an entity’s results of operations and financial position.
In September 2008, FASB Staff Position No. 133-1 and FASB Interpre-
tation No. 45-4 (the “FSP”), “Disclosures about Credit Derivatives and

10 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Notes to Financial Statements (concluded) CMA Government Securities Fund and CMA Treasury Fund

Certain Guarantees: An Amendment of FASB Statement No. 133 and
FASB Interpretation No. 45; and Clarification of the Effective Date of
FASB Statement No. 161” was issued and is effective for fiscal years
and interim periods ending after November 15, 2008. The FSP amends
FASB Statement No. 133, “Accounting for Derivative Instruments and
Hedging Activities,” to require disclosures by sellers of credit derivatives,
including credit derivatives embedded in hybrid instruments. The FSP
also clarifies the effective date of FAS 161, whereby disclosures required
by FAS 161 are effective for financial statements issued for fiscal years
and interim periods beginning after November 15, 2008. The impact
on the Funds' financial statement disclosures, if any, is currently
being assessed.

Other: Expenses directly related to each Fund are charged to that Fund.
Other operating expenses shared by several funds are pro-rated among
those funds on the basis of relative net assets or other appropriate
methods.

2. Transactions with Affiliates:

The Funds have entered into an Administration Agreement with
BlackRock Advisors, LLC (the “Administrator”), an indirect, wholly
owned subsidiary of BlackRock, Inc., to provide administrative services
(other than investment advice and related portfolio activities). For such
services, each Fund pays the Administrator a monthly fee at an annual
rate of 0.25% of the average daily value of each Fund’s net assets.
Merrill Lynch & Co., Inc. (“Merrill Lynch”) and The PNC Financial Services
Group, Inc. (“PNC”) are principal owners of BlackRock, Inc.

The Funds have also entered into a Distribution Agreement and a
Distribution and Shareholder Servicing Plan (the “Distribution Plan”)
with Merrill Lynch, Pierce, Fenner and Smith Incorporated (“MLPF&S”),
a wholly owned subsidiary of Merrill Lynch.

Pursuant to the Distribution Plan adopted by each Fund in accordance
with Rule 12b-1 under the 1940 Act, each Fund pays MLPF&S an
ongoing distribution fee accrued daily and paid monthly at an annual
rate of 0.125% of the average daily value of each Fund’s net assets for
shareholders whose Fund accounts are serviced by MLPF&S or directly
with the Funds’ transfer agent.

Financial Data Services, Inc. (“FDS”), a wholly owned subsidiary of
Merrill Lynch and an affiliate of the Administrator, serves as transfer
agent. Interest is earned by the Funds from FDS based on the difference,
if any, between estimated and actual daily share activity, which results in
uninvested net proceeds from sales of Fund shares. This is shown as
income from affiliates on the Statements of Operations.

Certain officers and/or directors of the Funds are officers and/or
directors of BlackRock, Inc. or its affiliates. The Funds reimburse
the Administrator for compensation paid to the Funds’ Chief
Compliance Officer.

3. Capital Share Transactions:

The number of shares sold, reinvested and redeemed during the past
two periods corresponds to the amounts included in the Statements
of Changes in Net Assets for net proceeds from the sale of shares,
reinvestment of dividends and distributions and cost of shares
redeemed, respectively, since shares are recorded at $1.00 per share.

4. Subsequent Events:

On September 15, 2008, Bank of America Corporation announced
that it has agreed to acquire Merril Lynch, one of the principal owners
of BlackRock, Inc. The purchase has been approved by the directors of
both companies. Subject to shareholder and regulatory approvals, the
transaction is expected to close on or before December 31, 2008.

Effective October 1, 2008, BlackRock Investments, Inc., an affiliate
of the Administrator, replaced MLPF&S as the sole distributor of the
Funds. The distribution fee will not change as a result of this transaction.

On October 9, 2008, the Board approved the Funds’ participation in
the U.S. Treasury Department Temporary Guarantee Program for Money
Market Funds (the “Program”). As a result of the Funds’ participating in
the Program, shareholders will have Federal insurance up to the lesser
of the amount of a shareholder’s balance in the Funds as of the close
of business on September 19, 2008, or the amount held in the Funds
on the date that a claim is filed for payment under the Program. Any
increase in the number of shares in a shareholder’s balance after the
close of business on September 19, 2008 and any future investments
after a shareholder has closed their account will not be guaranteed.
As a participant of the program, which expires December 18, 2008,
the Funds have paid a participation fee of 0.01% of the Funds’ shares
outstanding value as of September 19, 2008.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 11

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Portfolio Summary

Portfolio Composition as a Percent of Net Assets

	As of
Master Government Securities LLC	9/30/08	3/31/08
Repurchase Agreements	54%	71%
U.S. Government Obligations	46	33
Liabilities in Excess of Other Assets	—	(4)
Total	100%	100%

	As of
Master Treasury LLC	9/30/08	3/31/08
U.S. Government Obligations	102%	106%
Liabilities in Excess of Other Assets	(2)	(6)
Total	100%	100%

12 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Schedule of Investments September 30, 2008 (Unaudited) Master Government Securities LLC
(Percentages shown are based on Net Assets)

	Par
Issue	(000)	Value
U.S. Government Obligations — 46.3%
U.S. Treasury Bills (a):
1.83%, 10/02/08	$ 3,834	$   3,833,610
0.20% — 1.86%, 10/09/08	66,142	66,122,945
0.38%, 10/16/08	20,000	19,996,622
0.05%, 10/30/08	3,030	3,029,874
1.45% — 1.70%, 11/06/08	76,290	76,165,930
0.40%, 11/13/08	35,000	34,982,889
0.10% — 0.15%, 11/20/08	24,140	24,136,205
1.68% — 1.70%, 11/28/08	39,448	39,338,411
0.23% — 1.65%, 12/04/08	77,546	77,470,028
1.48% — 1.58%, 12/11/08	49,009	48,860,088
2.25%, 12/26/08	10,000	9,945,625
0.76% — 1.10%, 1/02/09	31,404	31,336,126
1.97%, 1/08/09	9,380	9,328,671
1.81%, 1/15/09	40,000	39,784,811
1.89% — 1.90%, 1/29/09	8,000	7,949,046
1.88% — 1.89%, 2/05/09	15,000	14,899,538
1.99% — 2.00%, 2/12/09	20,000	19,850,637
1.94%, 2/19/09	7,828	7,768,206
1.91%, 2/26/09	10,000	9,920,947
0.69%, 3/19/09	60,000	59,804,500
Total U.S. Government Obligations		604,524,709
Repurchase Agreements — 53.5%
Banc of America Securities Corp., purchased on
9/24/08 to yield 0.50% to 10/01/08, repurchase
price $63,706,193, collateralized by GNMA, 6.50%
due 9/20/38	63,700	63,700,000
Barclays Capital Inc., purchased on 7/28/08
to yield 2.20% to 10/27/08, repurchase price
$56,210,866, collateralized by U.S. Treasury Inflation
Bonds, 2.63% due 5/31/10	55,900	55,900,000
Citigroup Global Markets Inc., purchased on 9/24/08
to yield 1.20% to 10/01/08, repurchase price
$63,714,863, collateralized by GNMA, 6%
due 9/20/38	63,700	63,700,000
Credit Suisse Securities (USA) LLC, purchased on
8/01/08 to yield 2.25% to 11/03/08, repurchase
price $55,323,125, collateralized by GNMA,
5% to 7.50% due 9/15/13 to 9/15/38	55,000	55,000,000
Deutsche Bank Securities Inc., purchased on 9/24/08
to yield 2.25% to 10/01/08, repurchase price
$63,727,869, collateralized by GNMA, 5.50% to 7%
due 7/15/36 to 9/15/38	63,700	63,700,000

	Par
Issue	(000)	Value
Repurchase Agreements (concluded)
Goldman Sachs & Co., Inc., purchased on 7/15/08
to yield 2.04% to 10/14/08, repurchase price
$58,399,602, collateralized by GNMA, 4.50% to 6%
due 6/15/18 to 7/15/38	$ 58,100	$   58,100,000
Greenwich Capital Markets, Inc., purchased on
9/24/08 to yield 1.25% to 10/01/08, repurchase
price $63,715,483, collateralized by GNMA,
4.85% to 7% due 3/15/38 to 3/15/48	63,700	63,700,000
HSBC Securities (USA) Inc., purchased on 9/30/08
to yield 0.20% to 10/01/08, repurchase price
$62,500,347, collateralized by U.S. Treasury Inflation
Bonds, 2% due 1/15/26	62,500	62,500,000
J Morgan Securities Inc., purchased on 9/30/08
to yield 1% to 10/07/08, repurchase price
$62,512,153, collateralized by GNMA, 4.50% to 13%
due 10/15/08 to 2/15/49	62,500	62,500,000
Merrill Lynch Government Securities Inc., purchased
on 9/24/08 to yield 1.20% to 10/01/08,
repurchase price $63,714,863, collateralized by
GNMA, 5% to 7.50% due 12/20/21 to 2/20/38 (b)	63,700	63,700,000
Mizuho Securities USA LLC, purchased on 9/30/08
to yield 0.25% to 10/01/08, repurchase price
$28,000,194, collateralized by U.S. Treasury Bills,
due 9/24/09	28,000	28,000,000
UBS Securities LLC, purchased on 7/16/08 to yield
2.15% to 10/15/08, repurchase price 59,320,649,
collateralized by GNMA, 3.50% to 13.50%
due 12/15/08 to 9/15/38	59,000	59,000,000
Total Repurchase Agreements		699,500,000
Total Investments (Cost — $1,304,024,709*) — 99.8%		1,304,024,709
Other Assets Less Liabilities — 0.2%		2,794,270
Net Assets — 100.0%	$ 1,306,818,979
* Cost for federal income tax purposes.
(a) Traded on a discount basis. Rates shown are the discount rates or range of
discount rates paid at the time of purchase.
(b) Investments in companies considered to be an affiliate of the Master LLC, for
purposes of Section 2(a)(3) of the Investment Company Act of 1940, were
as follows:
	Net
	Activity
Affiliate	(000)	Income
Merrill Lynch Government Securities Inc.	$ (4,800)	$ 611,530

See Notes to Financial Statements.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 13

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Schedule of Investments (concluded) Master Government Securities LLC

_{• Effective April 1,2008,the Master LLC adopted Financial Accounting Standa rds}
Board Statement of Financial Accounting Standards No. 157, “Fair Value
Measurements” (“FAS 157”). FAS 157 clarifies the definition of fair value,
establishes a framework for measuring fair values and requires additional
disclosures about the use of fair value measurements. Various inputs are
used in determining the fair value of investments, which are as follows:
_{• Level 1 — price quotations in active markets/exchanges for identical}
securities
_{• Level 2 — other observable inputs (including,but not limited to: quoted}
prices for similar assets or liabilities in markets that are not active, inputs
other than quoted prices that are observable for the assets or liabilities
(such as interest rates, yield curves, volatilities, prepayment speeds, loss
severities, credit risks, and default rates) or other market-corroborated inputs)
_{• Level 3 — unobservable inputs based on the best information available}
in the circumstance, to the extent observable inputs are not available
(including the Master LLC’s own assumption used in determining the fair
value of investments)
The inputs or methodology used for valuing securities are not necessarily an
indication of the risk associated with investing in those securities. For infor-
mation about the Master LLC’s policy regarding valuation of investments and
other significant accounting policies, please refer to Note 1 of the Notes to
Financial Statements.

The following table summarizes the inputs used as of September 30, 2008
in determining the fair valuation of the Master LLC’s investments:

Valuation		Investments in
Inputs		Securities
Level 1		—
Level 2		$1,304,024,709
Level 3		—
Total		$1,304,024,709

See Notes to Financial Statements.

14 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Schedule of Investments September 30, 2008 (Unaudited) Master Treasury LLC
(Percentages shown are based on Net Assets)

	Par
Issue	(000)	Value
U.S. Government Obligations — 102.4%
U.S. Treasury Bills (a):
0.05% — 1.90%, 10/02/08	$ 785,943	$ 785,915,154
0.05% — 1.865%, 10/09/08	695,276	695,167,769
0.05% — 1.505%, 10/16/08	581,014	580,860,561
0.05% — 1.56%, 10/23/08	701,350	701,147,066
0.05% — 1.72%, 10/30/08	501,427	500,942,095
0.10% — 1.71%, 11/06/08	845,607	844,767,596
0.08% — 1.82%, 11/13/08	187,475	187,290,867
0.15% — 1.88%, 11/20/08	546,629	546,082,185
0.11% — 0.403%, 11/28/08	31,318	31,300,370
0.10% — 1.73%, 12/04/08	263,817	263,359,178
1.75%, 12/11/08	150,000	149,475,000
0.25% — 2.25%, 12/26/08	161,410	161,186,815
1.203% — 2.125%, 1/02/09	99,000	98,638,138
2.034% — 2.07%, 1/08/09	26,000	25,851,800
1.81% — 1.935%, 1/15/09	171,485	170,542,990
1.958%, 1/22/09	40,000	39,752,050
1.895% — 1.896%, 2/05/09	60,000	59,595,598
1.986% — 2.002%, 2/12/09	61,000	60,544,052
1.749% — 1.98%, 2/19/09	96,000	95,292,449
1.95%, 2/26/09	100,000	99,192,917
1.815%, 3/12/09	70,000	69,424,746
0.69% — 1.41%, 3/19/09	355,000	353,444,854
		6,519,774,250
U.S. Treasury Notes, 4.75%, 12/31/08	20,000	20,216,594
Total Investments
(Cost — $6,539,990,844*) — 102.4%		6,539,990,844
Liabilities in Excess of Other Assets — (2.4)%		(150,274,897)
Net Assets — 100.0%		$6,389,715,947

_{• Effective April 1,2008,the Master LLC adopted Financial Accounting Standards}
Board Statement of Financial Accounting Standards No. 157, “Fair Value
Measurements” (“FAS 157”). FAS 157 clarifies the definition of fair value, estab-
lishes a framework for measuring fair values and requires additional disclosures
about the use of fair value measurements. Various inputs are used in determin-
ing the fair value of investments, which are as follows:
_{• Level 1 — price quotations in active markets/exchanges for identical securities
• Level 2 — other observable inputs (including,but not limited to: quoted prices}
for similar assets or liabilities in markets that are not active, inputs other than
quoted prices that are observable for the assets or liabilities (such as interest
rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks,
and default rates) or other market-corroborated inputs)
_{• Level 3 — unobservable inputs based on the best information available in}
the circumstance, to the extent observable inputs are not available (includ-
ing the Master LLC’s own assumption used in determining the fair value
of investments)

The inputs or methodology used for valuing securities are not necessarily
an indication of the risk associated with investing in those securities. For infor-
mation about the Master LLC’s policy regarding valuation of investments and
other significant accounting policies, please refer to Note 1 of the Notes to
Financial Statements.

The following table summarizes the inputs used as of September 30, 2008 in
determining the fair valuation of the Master LLC’s investments:

Valuation		Investments in
Inputs		Securities
Level 1		—
Level 2		$6,539,990,844
Level 3		—
Total		$6,539,990,844

* Cost for federal income tax purposes.
(a) Traded on a discount basis. Rates shown are the discount rates or range of dis-
count rates paid at the time of purchase.

See Notes to Financial Statements.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 15

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Statements of Assets and Liabilities
		Master
		Government		Master
September 30, 2008 (Unaudited)		Securities LLC		Treasury LLC
Assets
Investments at value — unaffiliated 1		$ 604,524,709		$6,539,990,844
Repurchase agreements at value — unaffiliated 2		635,800,000		—
Repurchase agreements at value — affiliated 3		63,700,000		—
Cash		266		707
Investments sold receivable		—		290,541,608
Contributions receivable from investors		2,009,337		—
Interest receivable		1,014,132		232,155
Prepaid expenses		23,159		31,723
Total assets		1,307,071,603		6,830,797,037
Liabilities
Investments purchased payable		—		440,496,903
Investment advisory fees payable		190,960		491,211
Other affiliates payable		9,762		23,858
Withdrawals payable to investors		—		486
Officer’s and Directors’ fees payable		100		230
Other accrued expenses payable		51,802		68,402
Total liabilities		252,624		441,081,090
Net Assets		$1,306,818,979		$6,389,715,947
Net Assets Consist of
Investors’ capital		$1,306,818,979		$6,389,715,947
1 Investments at cost — unaffiliated		$ 604,524,709		$6,539,990,844
2 Repurchase agreements at cost — unaffiliated		$ 635,800,000		—
3 Repurchase agreements at cost — affiliated		$ 63,700,000		—

See Notes to Financial Statements.

16 SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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Statements of Operations
		Master
		Government		Master
Six Months Ended September 30, 2008 (Unaudited)		Securities LLC		Treasury LLC
Investment Income
Interest		$ 10,800,281		$ 26,624,665
Income from affiliates		611,530		—
Total Income		11,411,811		26,624,665
Expenses
Investment advisory		1,189,629		2,454,622
Accounting services		114,978		194,989
Custodian		32,280		40,490
Professional		22,813		23,397
Officer and Directors		15,312		22,451
Printing		662		1,381
Miscellaneous		8,767		12,442
Total expenses		1,384,441		2,749,772
Net investment income		10,027,370		23,874,893
Realized Gain
Net realized gain from investments		11,856		7,721
Net Increase in Net Assets Resulting from Operations		$ 10,039,226		$ 23,882,614

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

17

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Statements of Changes in Net Assets
		Master Government Securities LLC				Master Treasury LLC
		Six Months Ended				Six Months Ended
		September 30,		Year Ended		September 30,		Year Ended
		2008		March 31,		2008		March 31,
Increase (Decrease) in Net Assets:		(Unaudited)		2008		(Unaudited)		2008
Operations
Net investment income		$ 10,027,370		$ 42,522,869		$ 23,874,893		$ 52,666,503
Net realized gain		11,856		71,881		7,721		130,747
Net change in unrealized appreciation/depreciation		—		(27,831)		—		(186,066)
Net increase in net assets resulting from operations		10,039,226		42,566,919		23,882,614		52,611,184
Capital Transactions
Proceeds from contributions		3,091,226,130		6,967,978,832		13,032,158,513		12,960,360,648
Fair value of withdrawals		(3,102,568,544)		(6,666,836,245)		(10,152,643,720)		(10,401,372,105)
Net increase (decrease) in net assets derived from capital transactions		(11,342,414)		301,142,587		2,879,514,793		2,558,988,543
Net Assets
Total increase (decrease) in net assets		(1,303,188)		343,709,506		2,903,397,407		2,611,599,727
Beginning of period		1,308,122,167		964,412,661		3,486,318,540		874,718,813
End of period		$1,306,818,979		$ 1,308,122,167		$ 6,389,715,947		$ 3,486,318,540

See Notes to Financial Statements.

18 SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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Financial Highlights Master Government Securities LLC

¹ Aggregate total investment return.
² Annualized.

		Six Months Ended
		September 30,	Year Ended March 31,
		2008
		(Unaudited)	2008	2007	2006	2005	2004
Total Investment Return
Total investment return		0.85% 1	4.16%	4.90%	3.37%	1.44%	0.94%
Ratios to Average Net Assets
Total expenses		0.23% 2	0.24%	0.26%	0.26%	0.25%	0.22%
Net investment income		1.67% 2	3.99%	4.84%	3.31%	1.39%	0.94%
Supplemental Data
Net assets, end of period (000)		$ 1,306,819	$ 1,308,122	$ 964,413	$ 968,809 $	936,566	$ 1,194,238

Master Treasury LLC

		Six Months Ended
		September 30,	Year Ended March 31,
		2008
		(Unaudited)	2008	2007	2006	2005	2004
Total Investment Return
Total investment return		0.77% 1	3.87%	4.70%	3.22%	1.35%	0.81%
Ratios to Average Net Assets
Total expenses		0.17% 2	0.21%	0.26%	0.26%	0.25%	0.23%
Net investment income		1.48% 2	3.42%	4.63%	3.14%	1.34%	0.82%
Supplemental Data
Net assets, end of period (000)		$ 6,389,716	$ 3,486,319	$ 874,719	$ 873,537 $	969,383	$ 1,115,732

¹ Aggregate total investment return.
² Annualized.

See Notes to Financial Statements.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 19

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Notes to Financial Statements (Unaudited) Master Government Securities LLC and Master Treasury LLC

1. Significant Accounting Policies:

Master Government Securities LLC and Master Treasury LLC
(collectively the “Master LLCs”) are registered under the Investment
Company Act of 1940, as amended (the “1940 Act”), and are each
organized as Delaware limited liability companies. The Limited Liability
Company Agreement of each Master LLC permits the Directors to
issue non-transferable interests in the Master LLC, subject to certain
limitations. Throughout this report, the Board of Trustees is referred
to as the Board of Directors (the “Board”). The Master LLCs’ financial
statements are prepared in conformity with accounting principles gen-
erally accepted in the United States of America, which may require the
use of management accruals and estimates. Actual results may differ
from these estimates.

The following is a summary of significant accounting policies followed
by the Master LLCs:

Valuation of Investments: Master LLCs’ securities are valued under the
amortized cost method which approximates current market value in
accordance with Rule 2a-7 of the 1940 Act. Under this method, securi-
ties are valued at cost when purchased and thereafter, a constant pro-
portionate amortization of any discount or premium is recorded until the
maturity of the security.

Repurchase Agreements: The Master LLCs may invest in U.S. government
and agency securities pursuant to repurchase agreements. Under such
agreements, the counterparty agrees to repurchase the security at a
mutually agreed upon time and price. The counterparty will be required
on a daily basis to maintain the value of the securities subject to the
agreement at no less than the repurchase price. The agreements are
conditioned upon the collateral being deposited under the Federal
Reserve book entry system or held in a segregated account by each
of the Master LLC’s custodians. If the counterparty defaults and the
fair value of the collateral declines, liquidation of the collateral by
the Master LLCs may be delayed or limited.

Investment Transactions and Investment Income: Investment trans-
actions are recorded on the dates the transactions are entered into
(the trade dates). Realized gains and losses on security transactions
are determined on the identified cost basis. Interest income is recog-
nized on the accrual basis. The Master LLCs amortize all premiums
and discounts on debt securities.

Income Taxes: The Master LLCs are classified as a partnership for
federal income tax purposes. As such, each investor in a Master LLC is
treated as owner of its proportionate share of the net assets, income,
expenses and realized and unrealized gains and losses of the Master LLC.

Therefore, no federal income tax provision is required. It is intended that
the Master LLCs’ assets will be managed so an investor in the Master
LLCs can satisfy the requirements of Subchapter M of the Internal
Revenue Code. The Master LLCs are disregarded as an entity separate
from its owner for tax purposes, therefore they are not required to file
income tax returns.

Recent Accounting Pronouncement: In March 2008, Statement of
Financial Accounting Standards No. 161, “Disclosures about Derivative
Instruments and Hedging Activities — an amendment of FASB Statement
No. 133” (“FAS 161”), was issued. FAS 161 is intended to improve
financial reporting for derivative instruments by requiring enhanced
disclosure that enables investors to understand how and why an entity
uses derivatives, how derivatives are accounted for, and how derivative
instruments affect an entity’s results of operations and financial
position. In September 2008, FASB Staff Position No. 133-1 and
FASB Interpretation No. 45-4 (the “FSP”), “Disclosures about Credit
Derivatives and Certain Guarantees: An Amendment of FASB Statement
No. 133 and FASB Interpretation No. 45; and Clarification of the
Effective Date of FASB Statement No. 161” was issued and is effective
for fiscal years and interim periods ending after November 15, 2008.
The FSP amends FASB Statement No. 133, “Accounting for Derivative
Instruments and Hedging Activities,” to require disclosures by sellers of
credit derivatives, including credit derivatives embedded in hybrid instru-
ments. The FSP also clarifies the effective date of FAS 161, whereby
disclosures required by FAS 161 are effective for financial statements
issued for fiscal years and interim periods beginning after November 15,
2008. The impact on each Master LLC’s financial statement disclosures,
if any, is currently being assessed.

Other: Expenses directly related to each Master LLC are charged to
that Master LLC. Other operating expenses shared by several funds are
pro-rated among those funds on the basis of relative net assets or other
appropriate methods.

2. Investment Advisory Agreement and Other Transactions
with Affiliates:

Each Master LLC has entered into an Investment Advisory Agreement
with BlackRock Advisors, LLC (the “Advisor”), an indirect, wholly owned
subsidiary of BlackRock, Inc., to provide investment and administration
services. Merrill Lynch & Co., Inc. and The PNC Financial Services Group,
Inc. are principal owners of BlackRock, Inc.

The Advisor is responsible for the management of each Master LLC’s
portfolio and provides the necessary personnel, facilities, equipment and
certain other services necessary to the operations of the Master LLCs.
The Advisor also performs certain administrative services necessary for
the operation of the Master LLCs. For such services, the Master LLCs pay

20 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Notes to Financial Statements (concluded) Master Government Securities LLC and Master Treasury LLC

the Advisor a monthly fee based upon the average daily value of each
Master LLC’s net assets at the following annual rates: 0.25% of the
Master LLC’s average daily net assets not exceeding $500 million;
0.175% of the average daily net assets in excess of $500 million, but
not exceeding $1 billion; and 0.125% of the average daily net assets
in excess of $1 billion.

The Advisor has entered into a separate sub-advisory agreement with
respect to each Master LLC with BlackRock Institutional Management
Corporation (“BIMC”), an affiliate of the Advisor, under which the Advisor
pays BIMC, for services it provides, a monthly fee that is a percentage of
the investment advisory fee paid by the Master LLC to the Advisor.

For the six months ended September 30, 2008, the Master LLCs reim-
bursed the Advisor for certain accounting services, which are included in
accounting services in the Statements of Operations. The reimburse-
ments were as follows:

		Reimbursement
		to Advisor
Master Government Securities LLC		$ 9,585
Master Treasury LLC		$24,419

Certain officers and/or directors of the Master LLCs are officers
and/or directors of BlackRock, Inc. or its affiliates. The Master LLCs
reimburse the Advisor for compensation paid to the Master LLCs’
Chief Compliance Officer.

3. Subsequent Event:

On September 15, 2008, Bank of America Corporation announced that
it has agreed to acquire Merrill Lynch, one of the principal owners of
BlackRock, Inc. The purchase has been approved by the directors of
both companies. Subject to shareholder and regulatory approvals,
the transaction is expected to close on or before December 31, 2008.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 21

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Disclosure of Investment Advisory Agreement and Subadvisory Agreement

CMA Government Securities Fund (the “Government Fund”) currently
invests all of its investable assets in Master Government Securities LLC
(the “Master Government LLC”). CMA Treasury Fund (the “Treasury Fund,”
and together with the Government Fund, the “Funds”) currently invests all
of its investable assets in the Master Treasury LLC (the “Master Treasury
LLC,” and together with the Master Government LLC, the “Master LLCs”).
Accordingly, the Funds do not require investment advisory services, since
all investments are made at the Master LLC level.

The Board of Directors of each Master LLC met in person in April and
June 2008 to consider the approval of the Master LLC’s investment advi-
sory agreement entered into with BlackRock Advisors, LLC (the “Advisor”)
with respect to the relevant Fund (each, an “Advisory Agreement”). The
Board of each Master LLC also considered the approval of the sub-
advisory agreement between the Advisor and BlackRock Institutional
Management Corporation (the “Subadvisor”) with respect to the relevant
Fund (each, a “Subadvisory Agreement”). The Advisor and the Subadvisor
are referred to herein as “BlackRock.” The Advisory Agreements and
the Subadvisory Agreements are referred to herein as the “Agreements.”
Since each Fund invests all of its investable assets in the relevant Master
LLC, the Board of Trustees of each Fund also considered the approval
of the pertinent Agreements. For ease and clarity of presentation, the
Board of Directors of each Master LLC and the Board of Trustees of
each Fund, which are comprised of the same thirteen individuals, are
herein referred to collectively as the “Boards,” the members of which
are referred to as “Directors.”

Activities and Composition of the Boards

The Boards each consist of thirteen individuals, eleven of whom are not
“interested persons” of either the Funds or the Master LLCs as defined
in the Investment Company Act of 1940, as amended (the “1940 Act”)
(the “Independent Directors”). The Boards are responsible for the over-
sight of the operations of relevant Fund and Master LLC and perform the
various duties imposed on the directors of investment companies by the
1940 Act. The Independent Directors have retained independent legal
counsel to assist them in connection with their duties. The Co-Chairs
of each Board are both Independent Directors. The Boards established
four standing committees: an Audit Committee, a Governance and
Nominating Committee, a Compliance Committee and a Performance
Oversight Committee, each of which is composed of, and chaired by
Independent Directors.

The Agreements

Upon the consummation of the combination of BlackRock’s investment
management business with Merrill Lynch & Co., Inc.’s investment man-
agement business, including Merrill Lynch Investment Managers, L. . and
certain affiliates (the “Transaction”), each Master LLC entered into an

Advisory Agreement with respect to the relevant Fund with the Advisor
with an initial two-year term and the Advisor entered into a Subadvisory
Agreement with respect to the relevant with the Subadvisor with an initial
two-year term. Consistent with the 1940 Act, prior to the expiration of
each Agreement’s initial two-year term, the Boards are required to consider
the continuation of the Agreements on an annual basis. In connection
with this process, the Boards assessed, among other things, the nature,
scope and quality of the services provided to the relevant Fund and/or
Master LLC by the personnel of BlackRock and its affiliates, including
investment management, administrative services, shareholder services,
oversight of fund accounting and custody, marketing services and assis-
tance in meeting legal and regulatory requirements. The Boards also
received and assessed information regarding the services provided to the
relevant Fund and/or Master LLC by certain unaffiliated service providers.

Throughout the year, the Boards, acting directly and through their com-
mittees, consider at each of their meetings factors that are relevant to
their annual consideration of the renewal of the Agreements, including
the services and support provided to the relevant Fund and/or Master
LLC and their shareholders. Among the matters the Boards considered,
as pertinent, were: (a) investment performance for one, three and five
years, as applicable, against peer funds, as well as senior management’s
and portfolio managers’ analysis of the reasons for underperformance, if
applicable; (b) fees, including advisory, administration, if applicable, and
other fees paid to BlackRock and its affiliates by the Fund and/or the
Master LLC, such as transfer agency fees and fees for marketing and
distribution; (c) Fund and/or Master LLC operating expenses; (d) the
resources devoted to and compliance reports relating to the Fund’s and
the Master LLC’s investment objective, policies and restrictions, (e) the
Master LLC’s and the Fund’s compliance with their respective Code of
Ethics and compliance policies and procedures; (f) the nature, cost
and character of non-investment management services provided by
BlackRock and its affiliates; (g) BlackRock’s and other service providers’
internal controls; (h) BlackRock’s implementation of the proxy voting
guidelines approved by the Boards; (i) valuation and liquidity proce-
dures; and (j) periodic overview of BlackRock’s business, including
BlackRock’s response to the increasing scale of its business.

Board Considerations in Approving the Agreements

The Approval Process: Prior to the April 16, 2008 meeting at which
approval of the Agreements was to be considered, the Boards requested
and received materials specifically relating to the Agreements. The
Boards are engaged in an ongoing process with BlackRock to continu-
ously review the nature and scope of the information provided to better
assist their deliberations. These materials included (a) information
independently compiled and prepared by Lipper, Inc. (“Lipper”) on the
relevant Fund’s fees and expenses and the investment performance of

22 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Disclosure of Investment Advisory Agreement and Subadvisory Agreement (continued)

the Fund as compared with a peer group of funds as determined by
Lipper (“Peers”); (b) information on the profitability of the Agreements to
BlackRock and certain affiliates, including their other relationships with
the relevant Fund and/or Master LLC, and a discussion of fall-out bene-
fits; (c) a general analysis provided by BlackRock concerning investment
advisory fees charged to other clients, such as institutional and closed-
end funds, under similar investment mandates, as well as the perform-
ance of such other clients; (d) a report on economies of scale; (e) sales
and redemption data regarding the relevant Fund’s shares and the
Master LLC’s interests; and (f) an internal comparison of management
fees classified by Lipper, if applicable. At the April 16, 2008 meeting,
the Boards requested and subsequently received from BlackRock with
respect to each relevant Fund and Master LLC (i) comprehensive analy-
sis of total expenses on a fund-by-fund basis; (ii) further analysis of
investment performance; (iii) further data regarding Fund and Master
LLC profitability, Fund and Master LLC size and Fund and Master LLC
fee levels; and (iv) additional information on sales and redemptions.

The Boards also considered other matters they deemed important to the
approval process with respect to each relevant Fund and Master LLC,
such as payments made to BlackRock or its affiliates relating to the
distribution of the Fund’s shares, services related to the valuation and
pricing of portfolio holdings of the Master LLC, and direct and indirect
benefits to BlackRock and its affiliates from their relationship with the
Fund and the Master LLC. The Boards did not identify any particular
information as controlling, and each Director may have attributed
different weights to the various items considered.

At an in-person meeting held on April 16, 2008, the Boards discussed
and considered the proposed renewal of the pertinent Agreements. As a
result of the discussions, the Boards requested and BlackRock provided
additional information, as detailed above, in advance of the June 3 – 4,
2008 Board meeting. At the in-person meeting held on June 3 – 4,
2008, the Boards, including the Independent Directors, unanimously
approved, with respect to each pertinent Fund, the continuation of
(a) the Advisory Agreement between the Advisor and the relevant Master
LLC for a one-year term ending June 30, 2009 and (b) the related
Subadvisory Agreement between the Advisor and the Subadvisor for a
one-year term ending June 30, 2009. The Boards considered all factors
they believed relevant with respect to each Fund and Master LLC, as
applicable, including, among other factors: (i) the nature, extent and
quality of the services provided by BlackRock; (ii) the investment per-
formance of the Fund, the Master LLC and BlackRock portfolio manage-
ment; (iii) the advisory fee and the cost of the services and profits to be
realized by BlackRock and certain affiliates from the relationships with
the Fund and the Master LLC; and (iv) economies of scale.

A. Nature, Extent and Quality of the Services: The Boards, including the
Independent Directors, reviewed the nature, extent and quality of ser-
vices provided by BlackRock, including the investment advisory services
and the resulting performance of each relevant Fund and Master LLC.
The Boards compared each Fund’s performance to the performance of a
comparable group of mutual funds as classified by Lipper and the per-
formance of at least one relevant index or combination of indices. The
Boards met with BlackRock’s senior management personnel responsible
for investment operations, including the senior investment officers. The
Boards also reviewed the materials provided by each Master LLC’s port-
folio management team discussing the Master LLC’s performance and
investment objective, strategies and outlook.

The Boards considered, among other factors, the number, education and
experience of BlackRock’s investment personnel generally, and of each
Master LLC’s portfolio management team; BlackRock’s portfolio trading
capabilities; BlackRock’s use of technology; BlackRock’s commitment
to compliance; and BlackRock’s approach to training and retaining port-
folio managers and other research, advisory and management person-
nel. The Boards also reviewed BlackRock’s compensation structure with
respect to the portfolio management team of each Master LLC and
BlackRock’s ability to attract and retain high-quality talent.

In addition to advisory services, the Boards considered the quality of
the administrative and non-investment advisory services provided to the
Funds and Master LLCs. BlackRock and its affiliates provide the Funds
and the Master LLCs with certain administrative, transfer agency, share-
holder and other services (in addition to any such services provided to
the Funds and the Master LLCs by third parties) and officers and other
personnel as are necessary for the operations of the Funds and the
Master LLCs. In addition to investment advisory services, BlackRock
and its affiliates provide the Funds and the Master LLCs with other
services, including, as pertinent, (a) preparing disclosure documents,
such as the prospectus, the statement of additional information and
shareholder reports; (b) assisting with daily accounting and pricing;
(c) overseeing and coordinating the activities of other service providers;
(d) organizing Board meetings and preparing the materials for such
Board meetings; (e) providing legal and compliance support; and
(f) performing other administrative functions necessary for the operation
of the Funds and the Master LLCs, such as tax reporting and fulfilling
regulatory filing requirements. The Boards reviewed the structure and
duties of BlackRock’s fund administration, accounting, legal and com-
pliance departments.

B. The Investment Performance of the Funds, the Master LLCs and
BlackRock: The Boards, including the Independent Directors, also
reviewed and considered the performance history of each relevant Fund.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 23

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Disclosure of Investment Advisory Agreement and Subadvisory Agreement (continued)

In preparation for the April 16, 2008 meeting, the Boards were provided
with reports with respect to each Fund, independently prepared by
Lipper, which included a comprehensive analysis of the Fund perform-
ance. The Boards also reviewed a narrative and statistical analysis of
the Lipper data that was prepared by BlackRock, which analyzed various
factors that affect Lipper rankings. In connection with their review, the
Boards received and reviewed information regarding the investment per-
formance of the Fund (and the related performance of the Master LLC)
as compared to a representative group of similar funds as determined
by Lipper and to all funds in the Fund’s applicable Lipper category. The
Boards were provided with a description of the methodology used by
Lipper to select peer funds. The Boards regularly review the performance
of the relevant Fund and Master LLC throughout the year. The Boards
attach more importance to performance over relatively long periods of
time, typically three to five years.

The Boards noted with favor that BlackRock had generally avoided
significant credit quality and liquidity issues in the challenging fixed-
income market that prevailed during the past 18 months.

In considering the performance data provided by Lipper, the Boards
noted that the Government Fund’s investment performance during each
of the one-, three- and five-year periods was below the median for the
Fund’s Peers. The Boards discussed the performance issues of the
Government Fund with BlackRock. The Boards noted that although the
Government Fund had performed below the median for its Peers in each
of the periods, the underperformance of the Government Fund was not
significant (underperformance was not greater than 10% of their respec-
tive median return) for any such period. Further, BlackRock advised the
Boards that after discussion with Lipper, it was determined that in the
future the Government Fund will be included in a different peer group
composed of funds more comparable to the Fund.

The Boards noted that although the Treasury Fund performed below the
median of its peers for each of the one-, three- and five-year periods,
the underperformance of the Treasury Fund was not significant (under-
performance was not greater than 10% of their respective median
return) for any of these periods.

C. Consideration of the Advisory Fees and the Cost of the Services
and Profits to be Realized by BlackRock and its Affiliates from the
Relationship with Each Fund and Master LLC: The Boards, including
the Independent Directors, reviewed each Master LLC’s contractual advi-
sory fee rates compared with the other funds in the relevant Fund’s
Lipper category. They also compared each Fund’s total expenses to
those of other comparable funds. The Boards considered the services
provided and the fees charged by BlackRock to other types of clients
with similar investment mandates, including separately managed
institutional accounts.

The Boards received and reviewed statements relating to BlackRock’s
financial condition and profitability with respect to the services it provid-
ed to each Master LLC. The Boards were also provided with a profitability
analysis that detailed the revenues earned and the expenses incurred
by BlackRock and certain affiliates that provide services to the Master
LLCs. The Boards reviewed BlackRock’s profitability with respect to each
Master LLC and each fund the Boards currently oversee for the year
ended December 31, 2007 compared to aggregated profitability data
provided for the year ended December 31, 2005.

In addition, the Boards considered the cost of the services provided to
the relevant Fund and Master LLC by BlackRock, and BlackRock’s and its
affiliates’ profits relating to the management and distribution, as perti-
nent, of the Fund and the Master LLC and the other funds advised
by BlackRock and its affiliates. As part of their analysis, the Boards
reviewed BlackRock’s methodology in allocating its costs to the manage-
ment of the relevant Fund and Master LLC and concluded that there
was a reasonable basis for the allocation. The Boards also considered
whether BlackRock has the financial resources necessary to attract and
retain high quality investment management personnel to perform its
obligations under the Agreements and to continue to provide the high
quality of services that are expected by the Boards.

The Boards noted that each Master LLC was subject to contractual advi-
sory fees, prior to any expense reimbursements, lower than or equal to
the median of its Peers. The Boards also took into account that each
Master LLC’s advisory fee arrangement includes breakpoints that adjust
the fee rate downward as the size of the Master LLC increases, thereby
allowing shareholders the potential to participate in economies of scale.

D. Economies of Scale: The Boards, including the Independent Directors,
considered the extent to which economies of scale might be realized as
the assets of each relevant Fund and Master LLC increase and whether
there should be changes in the advisory fee rate or structure in order to
enable the Fund and the Master LLC to participate in these economies
of scale. The Boards, including the Independent Directors, considered
whether the shareholders would benefit from economies of scale and
whether there was potential for future realization of economies with
respect to each relevant Fund and Master LLC. The Boards considered
that the funds in the BlackRock fund complex share common resources
and, as a result, an increase in the overall size of the complex could
permit each fund to incur lower expenses than it would otherwise as a
stand-alone entity. The Boards also considered the anticipated efficien-
cies in the processes of BlackRock’s overall operations as it continues
to add personnel and commit capital to expand the scale of operations.
The Boards found, based on their review of comparable funds, that each
Fund’s/Master LLC’s management fee is appropriate in light of the scale
of the Fund/Master LLC.

24 SEMI-ANNUAL REPORT SEPTEMBER 30, 2008

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Disclosure of Investment Advisory Agreement and Subadvisory Agreement (concluded)

E. Other Factors: The Boards also took into account other ancillary or “fall-out” benefits that BlackRock may derive from its relationship with each Fund and related Master LLC, both tangible and intangible, such as BlackRock’s ability to leverage its investment professionals who manage other portfolios, an increase in BlackRock’s profile in the investment advisory community, and the engagement of BlackRock’s affiliates as service providers to the Fund and the Master LLC, including for adminis- trative, transfer agency and distribution services. The Boards also noted that BlackRock may use third party research, obtained by soft dollars generated by certain mutual fund transactions, to assist itself in manag- ing all or a number of its other client accounts. In connection with their consideration of the Agreements, the Boards also received information regarding BlackRock’s brokerage and trade execution practices throughout the year. Conclusion The Boards approved, with respect to each relevant Fund, the continua- tion of (a) the Advisory Agreement between the Advisor and the relevant Master LLC with respect to the Fund/Master LLC for a one-year term ending June 30, 2009 and (b) the related Subadvisory Agreement between the Advisor and Subadvisor for a one-year term ending June 30, 2009. Based upon their evaluation of all these factors in their totality, the Boards, including the Independent Directors, were satisfied that the terms of the Agreements were fair and reasonable and in the best interest of the relevant Fund and Master LLC and the Fund’s share- holders. In arriving at a decision to approve the Agreements, the Boards did not identify any single factor or group of factors as all-important or controlling, but considered all factors together. The Independent Directors were also assisted by the advice of independent legal counsel in making this determination. The contractual fee arrangements for each Fund and related Master LLC reflect the results of several years of review by the Directors and predecessor Directors, and discussions between the Directors (and predecessor Directors) and BlackRock (and predecessor advisors). Certain aspects of the arrangements may be the subject of more attention in some years than in others, and the Directors’ conclu- sions may be based in part on their consideration of these arrange- ments in prior years.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 25

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Officers and Directors
Ronald W. Forbes, Co-Chairman of the Board and Director		Custodian
Rodney D. Johnson, Co-Chairman of the Board and Director		State Street Bank and Trust Company
David O. Beim, Director		Boston, MA 02101
Richard S. Davis, Director
Henry Gabbay, Director		Transfer Agent
Dr. Matina Horner, Director		Financial Data Services, Inc.
Herbert I. London, Director		Jacksonville, FL 32246
Cynthia A. Montgomery, Director
		Accounting Agent
Joseph P. Platt, Jr., Director		State Street Bank and Trust Company
Robert C. Robb, Jr., Director		Princeton, NJ 08540
Toby Rosenblatt, Director
Kenneth L. Urish, Chairman of the Audit Committee and Director		Independent Registered Public Accounting Firm
Frederick W. Winter, Director		Deloitte & Touche LLP
Donald C. Burke, Fund President and Chief Executive Officer		Princeton, NJ 08540
Anne F. Ackerley, Vice President
Neal J. Andrews, Chief Financial Officer		Legal Counsel
Jay M. Fife, Treasurer		Sidley Austin LLP
Brian P. Kindelan, Chief Compliance Officer of the Funds		New York, NY 10019
Howard B. Surloff, Secretary

26 SEMI-ANNUAL REPORT

SEPTEMBER 30, 2008

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Additional Information

Availability of Quarterly Schedule of Investments

The Funds file their complete schedule of portfolio holdings with the Secu-
rities and Exchange Commission (“SEC”) for the first and third quarters
of each fiscal year on Form N-Q. The Funds’ Forms N-Q are available on
the SEC’s website at http://www.sec.gov and may also be reviewed and

copied at the SEC’s Public Reference Room in Washington, DC. Informa-
tion on the operation of the Public Reference Room may be obtained
by calling (800) SEC-0330. The Funds’ Forms N-Q may also be obtained
upon request and without charge by calling (800) 441-7762.

Electronic Delivery

Electronic copies of most financial reports and prospectuses are available
on the Funds’ website or shareholders can sign up for e-mail notifications
of quarterly statements, annual and semi-annual reports and prospec-
tuses by enrolling in the Funds’ electronic delivery program.

Shareholders Who Hold Accounts with Investment Advisors, Banks
or Brokerages:

Please contact your financial advisor to enroll. Please note that not
all investment advisors, banks or brokerages may offer this service.

General Information

The Funds will mail only one copy of shareholder documents, including
annual and semi-annual reports and proxy statements, to shareholders
with multiple accounts at the same address. This practice is commonly
called “householding” and it is intended to reduce expenses and eliminate
duplicate mailings of shareholder documents. Mailings of your shareholder

documents may be householded indefinitely unless you instruct us other-
wise. If you do not want the mailing of these documents to be combined
with those for other members of your household, please contact the Funds
at (800) 441-7762.

BlackRock Privacy Principles

BlackRock is committed to maintaining the privacy of its current and for-
mer fund investors and individual clients (collectively, “Clients”) and to
safeguarding their non-public personal information. The following infor-
mation is provided to help you understand what personal information
BlackRock collects, how we protect that information and why in certain
cases we share such information with select parties.

If you are located in a jurisdiction where specific laws, rules or regulations
require BlackRock to provide you with additional or different privacy-
related rights beyond what is set forth below, then BlackRock will comply
with those specific laws, rules or regulations.

BlackRock obtains or verifies personal non-public information from and
about you from different sources, including the following: (i) information
we receive from you or, if applicable, your financial intermediary, on appli-
cations, forms or other documents; (ii) information about your transac-
tions with us, our affiliates, or others; (iii) information we receive from a
consumer reporting agency; and (iv) from visits to our websites.

BlackRock does not sell or disclose to non-affiliated third parties any
non-public personal information about its Clients, except as permitted by
law or as is necessary to respond to regulatory requests or to service Client
accounts. These non-affiliated third parties are required to protect the
confidentiality and security of this information and to use it only for
its intended purpose.

We may share information with our affiliates to service your account or to
provide you with information about other BlackRock products or services
that may be of interest to you. In addition, BlackRock restricts access to
non-public personal information about its Clients to those BlackRock
employees with a legitimate business need for the information. BlackRock
maintains physical, electronic and procedural safeguards that are designed
to protect the non-public personal information of its Clients, including
procedures relating to the proper storage and disposal of such information.

SEMI-ANNUAL REPORT SEPTEMBER 30, 2008 27

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This report is transmitted to shareholders only. It is not authorized for use as an offer of sale or a solicitation of an offer to buy shares of the Funds unless accompanied or preceded by the Funds’ current prospectus. An investment in the Funds is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency other than with respect to the Funds’ participation in the U.S. Treasury Department Guarantee Program for Money Market Funds disclosed in this semi-annual report. Although the Funds seek to preserve the value of your investment at $1.00 per share, it is possible to lose money by investing in the Funds. Past performance results shown in this report should not be considered a representation of future performance. Total return information assumes reinvestment of all distributions. For current month-end performance information, call (800) 882-0052. The Funds’ current 7-day yield more closely reflects the current earnings of the Funds than the total returns quoted. Statements and other information herein are as dated and are subject to change. A description of the policies and procedures that the Funds use to determine how to vote proxies relating to portfolio securities is available (1) without charge, upon request, by calling toll- free (800) 441-7762; (2) at www.blackrock.com; and (3) on the Securities and Exchange Commission’s website at http://www.sec.gov. Information about how the Funds voted proxies relating to securities held in the Funds’ portfolio during the most recent 12-month period ended June 30 is available (1) at www.blackrock.com or by calling (800) 441-7762 and (2) on the Securities and Exchange Commission’s website at http://www.sec.gov.

CMA Government Securities Fund CMA Treasury Fund 100 Bellevue Parkway Wilmington, DE 19809

#CMAGOVTR-9/08

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Item 2 – Code of Ethics – Not Applicable to this semi-annual report Item 3 – Audit Committee Financial Expert – Not Applicable to this semi-annual report Item 4 – Principal Accountant Fees and Services – Not Applicable to this semi-annual report Item 5 – Audit Committee of Listed Registrants – Not Applicable Item 6 – Investments (a) The registrant’s Schedule of Investments is included as part of the Report to Stockholders filed under Item 1 of this form. (b) Not Applicable due to no such divestments during the semi-annual period covered since the previous Form N-CSR filing. Item 7 – Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies – Not Applicable Item 8 – Portfolio Managers of Closed-End Management Investment Companies – Not Applicable Item 9 – Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers – Not Applicable Item 10 – Submission of Matters to a Vote of Security Holders – The registrant’s Nominating and Governance Committee will consider nominees to the board of directors recommended by shareholders when a vacancy becomes available. Shareholders who wish to recommend a nominee should send nominations that include biographical information and set forth the qualifications of the proposed nominee to the registrant’s Secretary. There have been no material changes to these procedures. Item 11 – Controls and Procedures 11(a) – The registrant’s principal executive and principal financial officers or persons performing similar functions have concluded that the registrant’s disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the “1940 Act”)) are effective as of a date within 90 days of the filing of this report based on the evaluation of these controls and procedures required by Rule 30a-3(b) under the 1940 Act and Rule 15d-15(b) under the Securities Exchange Act of 1934, as amended. 11(b) – There were no changes in the registrant’s internal control over financial reporting (as defined in Rule 30a- 3(d) under the 1940 Act) that occurred during the second fiscal quarter of the period covered by this report that have materially affected, or are reasonably likely to materially affect, the registrant’s internal control over financial reporting. Item 12 – Exhibits attached hereto 12(a)(1) – Code of Ethics – Not Applicable to this semi-annual report 12(a)(2) – Certifications – Attached hereto 12(a)(3) – Not Applicable 12(b) – Certifications – Attached hereto Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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CMA Treasury Fund and Master Treasury LLC By: /s/ Donald C. Burke Donald C. Burke Chief Executive Officer of CMA Treasury Fund and Master Treasury LLC Date: November 24, 2008 Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated. By: /s/ Donald C. Burke Donald C. Burke Chief Executive Officer (principal executive officer) of CMA Treasury Fund and Master Treasury LLC Date: November 24, 2008 By: /s/ Neal J. Andrews Neal J. Andrews Chief Financial Officer (principal financial officer) of CMA Treasury Fund and Master Treasury LLC Date: November 24, 2008

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