Plastic Tree Armatures 2" - 3" Deciduous from Woodland Scenics. Bend plastic Tree Armatures into any shape. This package contains 57 deciduous Tree Armatures from 2 to 3 inches tall. In scale, these trees would be approximately this tall: 27 to 40 feet tall (N scale); 15 to 22 feet tall (HO scale); and 8 to 12 feet tall (O scale).