7 U.S.C. § 2224

Employees of the Division of Accounts and Disbursements may be detailed by the Secretary of Agriculture for accounting and disbursing work in any of the bureaus and offices of the department for duty in or out of the city of Washington, and employees of the bureaus and offices of the department may also be detailed to the Division of Accounts and Disbursements for duty in or out of the city of Washington, traveling expenses of employees so detailed to be paid from the appropriation of the bureau or office in connection with which such travel is performed.