Lightly grease a baking sheet; set aside. In a medium bowl stir together flour, sugar, baking powder, lemon peel, tarragon, and baking soda. Using a pastry blender, cut in butter until mixture resembles coarse crumbs. Make a well in the center of flour mixture. Add the egg and buttermilk all at once. Using a fork, stir just until moistened.
Turn dough out onto a lightly floured surface. Quickly knead dough by gently folding and pressing for 10 to 12 strokes or until nearly smooth. Lightly roll dough into a 12x6-inch rectangle. Cut into twenty-four 6x1/2-inch strips.
Place strips 1/2 inch apart on the prepared baking sheet. Brush with additional buttermilk. If desired, sprinkle with poppy seeds.
Bake in a 425 degree F oven about 10 minutes or until golden brown. Remove from baking sheet and cool slightly on a wire rack. Serve warm.Makes 24 biscuit sticks.