INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO § 240.13d-1(a) AND AMENDMENTS THERETO FILED PURSUANT TO

§ 240.13d-2(a)

(Amendment No.     )*

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

Note. Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See § 240.13d-7 for other parties to whom copies are to be sent.

(Continued on following pages)

(Page 1 of 14)

* The remainder of this cover page shall be filled out for a reporting person's initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (the “Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

(1) Based on 99,786,406 shares of common stock, without par value, of the Company outstanding as of July 24, 2009, as set forth in the Company’s Form 10-Q for the quarterly period ended June 30, 2009.

(2) Based on 99,786,406 shares of common stock, without par value, of the Company outstanding as of July 24, 2009, as set forth in the Company’s Form 10-Q for the quarterly period ended June 30, 2009.

(3) Based on 99,786,406 shares of common stock, without par value, of the Company outstanding as of July 24, 2009, as set forth in the Company’s Form 10-Q for the quarterly period ended June 30, 2009.

Item 1.            Security and Issuer.

This statement on Schedule 13D (this “Statement”) relates to the shares of common stock, without par value (the “Company Shares”), of Terra Industries Inc., a Maryland corporation (the “Company”).  The Company’s principal executive offices are located at Terra Centre, 600 Fourth Street, P.O. Box 6000, Sioux City, Iowa 51102-6000.

Item 2.            Identity and Background.

This Statement is being filed by CF Industries Holdings, Inc., a Delaware corporation (“CF Holdings”), CF Industries, Inc., a Delaware corporation and wholly-owned subsidiary of CF Holdings (“CF Industries”), and CF Composite, Inc., a New York corporation and wholly-owned subsidiary of CF Industries (“CF Composite” and, together with CF Holdings and CF Industries, the “Reporting Persons”).

CF Holdings is the holding company for the operations of CF Industries. CF Industries is a major producer and distributor of nitrogen and phosphate fertilizer products. CF Industries operates world-scale nitrogen fertilizer plants in Donaldsonville, Louisiana and Medicine Hat, Alberta, Canada; conducts phosphate mining and manufacturing operations in Central Florida; and distributes fertilizer products through a system of terminals, warehouses and associated transportation equipment located primarily in the midwestern United States. CF Holdings, through an indirect wholly-owned subsidiary, also owns a 50% interest in KEYTRADE AG, a global fertilizer trading organization headquartered near Zurich, Switzerland. CF Composite, an indirect wholly-owned subsidiary of CF Holdings and a direct wholly-owned subsidiary of CF Industries, has not carried on any activities other than as described in Item 4 below. The address of the principal business and the address of the principal office of each of the Reporting Persons is 4 Parkway North, Suite 400, Deerfield, Illinois 60015-2590.

(a)–(f) The name, business address, present principal occupation or employment and citizenship of each executive officer and director of each of the Reporting Persons is set forth on Schedule A to this Statement, which is incorporated herein by reference.

(d) During the last five years, neither the Reporting Persons nor, to the best of the Reporting Persons’ knowledge, any person named on Schedule A hereto, has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

(e) During the last five years, neither the Reporting Persons nor, to the best of the Reporting Persons’ knowledge, any person named on Schedule A hereto, was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activity subject to, federal or state securities laws or finding any violation with respect to such laws.

Item 3.            Source and Amount of Funds or Other Consideration.

The aggregate purchase price the Reporting Persons paid for the Company Shares reported on this Statement (the “Purchased Shares”) was $247,063,409. The source of funding

for the purchase of the Purchased Shares was the general working capital of CF Industries. No part of the purchase price of the Purchased Shares is or will be represented by funds or other consideration borrowed or otherwise obtained for the purpose of acquiring, holding, trading or voting the Purchased Shares.

Item 4.            Purpose of Transaction.

The Reporting Persons acquired the Purchased Shares to further CF Holdings’ proposal for a business combination with the Company.

CF Holdings’ Proposals and Actions Related to a Business Combination with the Company

On January 15, 2009, CF Holdings delivered a letter to the board of directors of the Company (the “Board”) setting forth a proposal for a business combination with the Company, whereby CF Holdings would acquire all of the outstanding Company Shares at a fixed exchange ratio of 0.4235 shares of CF Holdings common stock, par value $0.01 per share (the “CF Shares”), for each Company Share.  A copy of CF Holdings’ letter to the Board, dated January 15, 2009, is filed as Exhibit 1 hereto and incorporated herein by reference.  On January 28, 2009, the Board rejected CF Holdings’ proposal.

On February 23, 2009, CF Holdings and a wholly-owned subsidiary commenced an exchange offer for all of the outstanding Company Shares at an exchange ratio of 0.4235 CF Shares for each Company Share (the “Exchange Offer”).

On March 9, 2009, CF Holdings delivered a letter to the Board stating that CF Holdings would be prepared to enter into a negotiated merger agreement with the Company that provides for an exchange ratio based on $27.50 for each Company Share, with an exchange ratio of not less than 0.4129 and not more than 0.4539 CF Shares for each Company Share. In addition, CF Holdings stated in such letter that CF Holdings would be prepared to enter into a negotiated merger agreement with the Company that restructured the consideration in the proposed transaction to include shares of a newly issued CF Holdings participating preferred stock. A copy of CF Holdings’ letter to the Board, dated March 9, 2009, is filed as Exhibit 2 hereto and incorporated herein by reference. On March 11, 2009, the Board rejected CF Holdings’ proposal.

On March 23, 2009, CF Holdings delivered a letter to the Board stating that CF Holdings would be prepared to enter into a negotiated merger agreement with the Company, structured as outlined in CF Holdings’ letter to the Board on March 9, 2009, with an exchange ratio based on $30.50 for each Company Share, the exchange ratio to be not less than 0.4129 and not more than 0.4539 CF Shares for each Company Share.  A copy of CF Holdings’ letter to the Board, dated March 23, 2009, is filed as Exhibit 3 hereto and incorporated herein by reference.  On March 24, 2009, the Board rejected CF Holdings’ proposal.

On June 19, 2009, CF Holdings received a standard, unqualified “no action” letter from the Canadian Competition Bureau confirming that the Canadian Commissioner of Competition does not intend to challenge CF Holdings’ proposed business combination with the Company.

On August 5, 2009, CF Holdings delivered a letter to the Board stating that CF Holdings would be prepared to enter into a negotiated merger agreement with the Company that provides for a fixed exchange ratio of 0.4650 CF Shares for each Company Share, the return of a substantial amount of cash to the stockholders of the combined company and the issuance of “contingent future shares” to CF Holdings’ stockholders immediately prior to the closing of the proposed business combination that would convert into CF Shares under certain circumstances.  A copy of CF Holdings’ letter to the Board, dated August 5, 2009, is filed as Exhibit 4 hereto and incorporated herein by reference. On August 25, 2009, the Board rejected CF Holdings’ proposal.

On August 6, 2009, CF Holdings announced that the premerger waiting period applicable to the proposed business combination with the Company under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, expired at 11:59 p.m. on August 5, 2009.

On August 12, 2009, CF Holdings received a letter from the U.S. Federal Trade Commission stating that it had closed its investigation into CF Holdings’ proposed business combination with the Company.

On August 31, 2009, the Exchange Offer expired in accordance with its terms without CF Holdings purchasing any Company Shares thereunder.

As described in Item 5 below, between September 10, 2009 and September 25, 2009, CF Industries purchased 6,985,048 Company Shares, constituting approximately 7.0% of the outstanding Company Shares, in open market transactions for an aggregate purchase price of approximately $247 million.

On September 24, 2009, the Company announced plans for a special cash dividend of $7.50 per Company Share, an aggregate of approximately $750 million, which the Company expected to declare and pay in the fourth quarter of 2009.  The Company also announced the commencement of a tender offer and consent solicitation to purchase any and all outstanding 7.00% Senior Notes due 2017 of the Company (the “2017 Notes”) for cash at a price equal to 104.5% of par, including a consent fee. In addition, the Company announced plans to raise up to $600 million of capital through a debt financing.

On September 28, 2009, in addition to filing this Statement, CF Holdings delivered to the Company a proposed draft form of merger agreement setting forth the terms of the proposed business combination between CF Holdings and the Company (the “Proposed Merger Agreement”). Among other things, the Proposed Merger Agreement contains the terms of the proposed merger pursuant to which the business combination would be effected, the conditions to the consummation of the merger, and the parties’ respective representations, warranties, covenants and agreements in connection therewith.  Under the terms of the Proposed Merger Agreement, upon the closing of the transaction, each outstanding Company Share would be converted into the right to receive 0.4650 CF Shares (the “Exchange Ratio”). If the Company declares the special dividend of $7.50 per Company Share that the Company announced on September 24, 2009, the Exchange Ratio would be appropriately adjusted based on trading

prices of CF Shares for an agreed period prior to the closing of the transaction. Under the terms of the Proposed Merger Agreement, the Company would also have the option to cause CF Holdings to issue, in lieu of the common stock consideration, a combination of a fraction of a CF Share and a fraction of a share of a new series of CF Holdings participating preferred stock, which is intended to be equivalent in value, in the aggregate, to 0.4650 CF Shares (or the applicable adjusted Exchange Ratio if the Company declares the special dividend); however, the Company’s election of such option would only become effective if CF Holdings stockholders do not approve the issuance of the CF Shares in the transaction. The terms of the Proposed Merger Agreement include that CF Holdings would issue contingent future shares to CF Holdings’ stockholders immediately prior to the closing of the business combination that would convert into an aggregate of 5 million CF Shares if for a specified period following the business combination CF Shares trade at over $125 per share.  In addition to other customary closing conditions, the Proposed Merger Agreement is conditioned upon the Company exercising its right, pursuant to the provisions of the charter of the Company establishing the terms of the 4.25% Series A Cumulative Convertible Perpetual Preferred Shares, without par value, of the Company, to require all holders of such shares to exchange such shares for convertible subordinated debentures of the Company.  In addition to the conditions set forth in the Proposed Merger Agreement, the proposed business combination is subject to approval by the Board and CF Holdings’ satisfactory completion of confirmatory due diligence on the Company and its subsidiaries.

The Proposed Merger Agreement also contains provisions relating to the Board and the Company’s officers and charter and bylaws following the proposed merger. Pursuant to the Proposed Merger Agreement, at the effective time of the proposed merger, the directors and officers of CF Holdings’ wholly-owned merger subsidiary (“Merger Sub”) would become the initial directors and officers of the Company. The existing directors of Merger Sub are Stephen R. Wilson, Anthony J. Nocchiero and Douglas C. Barnard. The existing officers of Merger Sub are Stephen R. Wilson, President, Douglas C. Barnard, Vice President and Secretary, and Anthony J. Nocchiero, Vice President, Treasurer, and Assistant Secretary. Also pursuant to the Proposed Merger Agreement, at the effective time of the proposed merger, the Company’s charter would be amended and restated in its entirety as set forth in an exhibit to be attached to the Proposed Merger Agreement, and, as so amended, would be the charter of the Company until amended as provided therein or by applicable law. The amended and restated charter would amend the Company’s current charter to simplify the authorized capital stock, eliminate provisions relating to takeover defenses and otherwise contain customary provisions for a wholly-owned subsidiary of a public company. Pursuant to the Proposed Merger Agreement, at the effective time of the proposed merger, the bylaws of Merger Sub would become the bylaws of the Company until amended as provided therein or by applicable law. The new bylaws would eliminate provisions related to takeover defenses contained in the Company’s current bylaws and otherwise contain customary provisions for a wholly-owned subsidiary of a public company. In addition, upon consummation of the proposed merger, the Company Shares would be delisted from the New York Stock Exchange and would become eligible for termination of registration pursuant to Section 12(g)(4) of the Securities Act.

A copy of the Proposed Merger Agreement, including term sheets for the preferred stock and contingent future shares, is filed as Exhibit 5 hereto and incorporated herein by reference.  The above summary and description of the Proposed Merger Agreement is qualified in its entirety by reference to such Exhibit 5.

Election of Directors at the Company’s 2009 Annual Meeting of Stockholders

To further CF Holdings’ proposal for a business combination with the Company, CF Composite, the record owner of 1,000 Company Shares, nominated three individuals for election as directors of the Company at the Company’s 2009 Annual Meeting of Stockholders of the Company (the “2009 Annual Meeting”).  CF Composite nominated the three nominees, John N. Lilly, David A. Wilson and Irving B. Yoskowitz (the “Nominees”), by delivering a notice to the Company on February 3, 2009, in accordance with the Amended and Restated Bylaws of the Company (the “Bylaws”).

On April 14, 2009, the Company announced that on and effective April 13, 2009, the Board had amended the Bylaws in order to eliminate the requirement that the Company’s annual meeting of stockholders be held during the period from April 15 to May 15 of each calendar year and to instead provide that the Company’s annual meeting of stockholders be held on such day of each calendar year as shall be designated by the Board.

On August 31, 2009, as the Company had not yet announced a date for the 2009 Annual Meeting, CF Composite filed a complaint in the Circuit Court for Baltimore City, captioned CF Composite, Inc. v. Terra Industries Inc., requesting that the court compel the Company to schedule the 2009 Annual Meeting immediately and hold the 2009 Annual Meeting as soon as reasonably possible.

Later on August 31, 2009, the Company announced that it planned to hold the 2009 Annual Meeting on Thursday, November 19, 2009.

On September 8, 2009, the Company announced that it planned to hold the 2009 Annual Meeting on Friday, November 20, 2009.

On September 9, 2009, because the Company scheduled the 2009 Annual Meeting for a date that is more than 60 days after the anniversary date of the 2008 Annual Meeting of Stockholders of the Company, CF Composite resubmitted to the Company its nomination of the Nominees for election as directors of the Company at the 2009 Annual Meeting, notwithstanding CF Composite’s earlier nomination of the Nominees in accordance with the Bylaws.

CF Holdings and CF Composite intend to solicit proxies from the Company’s stockholders for the 2009 Annual Meeting with respect to the Nominees’ election to the Board to give the Company’s stockholders a means of showing their support for a business combination between CF Holdings and the Company. Because the proposed business combination between CF Holdings and the Company may only proceed with the approval of the Board, the election of the Nominees is an important step toward a possible transaction between CF Holdings and the Company. The Board currently consists of eight directors, divided into three separate classes which are elected to staggered three year terms. Only one class of directors is elected per year. As a result, if the Nominees are elected to the Board, they will not constitute a majority of the Board. If necessary, CF Holdings presently intends to nominate additional persons to be considered for election to the Board at the Company’s 2010 Annual Meeting of Stockholders and to ultimately replace a majority of the members of the Board with nominees selected by CF Holdings.

The Reporting Persons intend to vote all of the Company Shares that they beneficially own for the election of the Nominees at the 2009 Annual Meeting.

Potential Changes to the Company’s Business Following Consummation of the Proposed Business Combination

Following the consummation of the proposed business combination or if CF Holdings otherwise obtains access to the books and records of the Company, CF Holdings intends to conduct a detailed review of the Company’s business, operations, capitalization and management and consider and determine what, if any, changes would be desirable in light of the circumstances which then exist. It is expected that, initially following the proposed business combination, the business and operations of the Company will, except as set forth in the Proposed Merger Agreement, be continued substantially as they are currently being conducted, but CF Holdings expressly reserves the right to make any changes that it deems necessary, appropriate or convenient to optimize the Company’s potential in conjunction with CF Holdings’ businesses or in light of future developments. Such changes could include, among other things, changes in the Company’s business, corporate structure, assets, properties, marketing strategies, capitalization, management, personnel or dividend policy and additional changes to the Company’s charter and bylaws. As noted above, on September 24, 2009, the Company announced the commencement of a tender offer and consent solicitation to purchase any and all of its outstanding 2017 Notes and announced plans to raise up to $600 million of capital through a debt financing.

Other

CF Holdings may in the future modify its objectives and proposals regarding the Company. CF Holdings and its representatives and advisors intend to continue to pursue negotiations with the Company and its advisors regarding a business combination with the Company. CF Holdings and its representatives and advisors also intend to communicate formally and informally with other stockholders of the Company, industry participants and other interested parties concerning a business combination with the Company.

The Reporting Persons may exercise any and all of their rights as stockholders of the Company in a manner consistent with their equity interests and investment objectives. The Reporting Persons may from time-to-time (i) acquire additional Company Shares (subject to availability at prices deemed favorable) in the open market, in privately negotiated transactions or otherwise, or (ii) dispose of Company Shares at prices deemed favorable in the open market, in privately negotiated transactions or otherwise. The Reporting Persons reserve the right to formulate other plans and/or make other proposals, and take such actions with respect to Company Shares beneficially owned by the Reporting Persons, including any or all of the actions set forth in paragraphs (a) through (j) of Item 4 of Schedule 13D and any other actions as the Reporting Persons may determine.

Except as described herein or as would occur upon completion of any of the actions described herein, the Reporting Persons do not and, to the best of the Reporting Persons’ knowledge, the persons named on Schedule A hereto do not, as of the date of this Statement, have any specific

plans or proposals that relate to or would result in any of the transactions described in paragraphs (a) through (j) of Item 4 of Schedule 13D.

Item 5.                                   Interest in Securities of the Issuer.

(a) According to the Company’s Quarterly Report on Form 10-Q for the quarterly period ended June 30, 2009, there were 99,786,406 Company Shares outstanding as of July 24, 2009.

The Reporting Persons beneficially own, in the aggregate, 6,986,048 Company Shares, or approximately 7.0% of the outstanding Company Shares. Of such shares: (i) 6,985,048 Company Shares, or approximately 7.0% of the outstanding Company Shares, are (a) owned directly by CF Industries and (b) beneficially owned by CF Holdings, as the owner of 100% of the capital stock of CF Industries, and CF Composite, as a direct wholly-owned subsidiary of CF Industries; and (ii) 1,000 Company Shares, or approximately .001% of the outstanding Company Shares, are (a) owned directly by CF Composite and (b) beneficially owned by CF Holdings and CF Industries.

To the best of the Reporting Persons’ knowledge, none of the persons named on Schedule A hereto is the beneficial owner of any Company Shares.

(b) The Reporting Persons have the shared power to vote or direct the vote, and the shared power to dispose or direct the disposition, of the Purchased Shares.

(c) Except as set forth on Schedule B hereto, neither the Reporting Persons nor, to the best of the Reporting Persons’ knowledge, any person named on Schedule A hereto, has effected any transaction in the Company Shares during the past 60 days.

(d) Not applicable.

(e) Not applicable.

Item 6.                                   Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer.

CF Industries is party to a Credit Agreement, dated as of August 16, 2005, as amended, with CF Holdings, CF Composite, the other loan guarantors party thereto, the lenders party thereto and JPMorgan Chase Bank, N.A., as Administrative Agent (the “Credit Agreement”). Under the terms of the Credit Agreement and related documents, obligations under the Credit Agreement are secured by, among other things, substantially all of the personal property and assets, both tangible and intangible, of CF Industries, including the Purchased Shares. No borrowings under the Credit Agreement were used by the Reporting Persons to finance the Reporting Persons’ acquisition of beneficial ownership of the Purchased Shares. Copies of the Credit Agreement and the amendments thereto are filed as Exhibits 6, 7, and 8 to this Statement.

Other than as described in Items 4, 5 and 6 hereof and the documents attached as exhibits hereto, neither the Reporting Persons nor, to the best of the Reporting Persons’ knowledge, any person named on Schedule A hereto, has any contracts, arrangements, understandings or relationships (legal or otherwise) among the persons named in Item 2 and between such persons and any person with respect to any securities of the Company, including but not limited to

transfer or voting of any of the securities, finder’s fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or loss, or the giving or withholding of proxies.

Item 7.                                   Material to be Filed as Exhibits.

The following documents are filed as exhibits:

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date:  September 28, 2009

EXHIBIT INDEX

SCHEDULE A

EXECUTIVE OFFICERS AND DIRECTORS OF REPORTING PERSONS

The following is a list of the executive officers and directors of the Reporting Persons, setting forth the present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted for each such person.  Unless otherwise indicated, the current business address of each person is 4 Parkway North, Suite 400, Deerfield, Illinois 60015-2590. All executive officers and directors listed below are citizens of the United States. Capitalized terms used but not otherwise defined in this Schedule A have the meaning ascribed to them in the Schedule 13D to which this Schedule A is attached.

Board of Directors of CF Holdings

1

Executive Officers of CF Holdings

2

Board of Directors of CF Industries

3

Executive Officers of CF Industries

4

Board of Directors of CF Composite

5

Executive Officers of CF Composite

6

SCHEDULE B

Certain Information Required by Item 5 of Schedule 13D

(c) During the past 60 days, CF Industries purchased Terra Shares in open market transactions as indicated below. The price per share excludes brokerage commissions.

September 10, 2009

1

2

September 11, 2009

3

4

September 14, 2009

5

September 15, 2009

6

7