picket n Cp DAE ~ 5 'thin, narrow strip of wood used as a lath or as a paling for a fence' (1800-), ~ fence [open fence] (1800-). A tall, slender, uniform, round stick of fir or spruce, with or without bark, placed vertically for fencing. Attrib ~ fence.
1842 BONNYCASTLE i, 292 Fences here are made ... by placing pickets, or small sticks, close alongside of each other, with the ends in the ground, and then nailing a riband over the whole, at about two feet, or so from the top; these fences are called, in the 'vernacular,' picket fences. 1946 MACKAY (ed) 153 There is a picturesqueness about the Newfoundland settlement with its houses huddled together without rhyme or reason, its narrow roadways, and its distinctive 'Picket' fences of tiny, trimmed trees. T 43/7-64 If you had a bit of a front garden you'd get palings for that, but the pasture fields or the gardens were fenced with pickets. 1971 NOSEWORTHY 230 Pickets. Small, 'green,' round sticks with the rind removed. Made from small trees. 1979 Evening Telegram 25 Aug, p. 8 'Diter Walls' were rock walls. The farmers of long ago, when clearing land, put all their boulders in straight lines. In that way you didn't have to go in the woods and cut pickets.
