Evergreens provide interest in the winter landscape and deep shade in the summer landscape. Botanists identify evergreen species by their needles, bark, and cones. Most evergreens grow in the classic pyramidal shape with horizontal spreading branches that grow longer every year, making the lower branches much longer and wider spreading than the upper branches. Seeds are borne in cones and some varieties keep their cones on the tree for many months.
The classic evergreen, pine trees (Pinus spp.) grow in a pyramidal shape with spreading branches. Pine trees have soft needles that are slender and borne in bundles of five. The bark on young twigs is a purplish color and buds are pronounced with overlapping scales that are arranged similar to fish scales. Cones are twice as long as wide.
Widely planted around foundations and as privacy fences, arborvitae (Thuja spp.) have flattened, scale-like leaves that grow opposite on small branchlets. The tops of the leaves are dark or bright green, with the underside a bluish green. Mature specimens of tree arborvitae varieties can reach 50 feet high. Monoecious flowers appear in clusters of all male or all female on the same tree. Small cones drop off in winter.
Another pyramid-shaped evergreen, fir (Abies spp.) trees have thin, smooth bark that becomes thicker and more furrowed as the trees age. The bluish-green needles are narrow and linear, curving upward and outward. The cones are borne upright and the scales are individually shed, which leaves behind an upright stick that protrudes above the branch.