Thomas Main (ca. 1753–by 1814), nurseryman, was a native of Scotland who rented land about 1803 near the Little Falls of the Potomac, two miles from Georgetown in the District of Columbia. After first attempting to establish a vineyard, he turned his attention to the cultivation of indigenous thorn bushes and fruit trees. Between 1805 and 1807 Main sold TJ apple, mulberry, peach, and other varieties of trees, as well as grapevines and thousands of Washington hawthorn seedlings for the creation of live fences at Monticello. The hawthorn hedges failed to prosper, however, and by 1811 they had been largely abandoned (David B. Warden, A Chorographical and Statistical Description of the District of Columbia [Paris, 1816], 117–20; MB description begins James A. Bear Jr. and Lucia C. Stanton, eds., Jefferson’s Memorandum Books: Accounts, with Legal Records and Miscellany, 1767–1826, 1997, The Papers of Thomas Jefferson, Second Series description ends , 2:1148, 1182–3, 1208, 1216; Betts, Garden Book description begins Edwin M. Betts, ed., Thomas Jefferson’s Garden Book, 1766–1824, 1944 description ends , 299, 313, 334, 342, 386; Joseph C. Cabell to TJ, 4 July 1816; Peter Hatch, The Fruits and Fruit Trees of Monticello [1998], 27, 73, 88, 135, 154–5; Washington National Intelligencer, 15 Feb. 1814).

Based on TJ’s response of 20 Jan. 1810, the enclosed paper, not found, was probably an unsuccessful prospectus for either a new work on hawthorn cultivation or a new edition of Main’s earlier pamphlet, Directions for the Transplantation and Management of young Thorn or other Hedge Plants, preparative to their being set in Hedges (Washington, 1807; Sowerby, description begins E. Millicent Sowerby, comp., Catalogue of the Library of Thomas Jefferson, 1952–59, 5 vols. description ends no. 723). During his presidency TJ failed to lure Main to more fertile fields in Virginia (TJ to James Currie, 29 Oct. 1805 [MHi]; Main to TJ, 29 Oct. [MHi], 18 Nov. 1805 [DLC]).