Thuja occidentalis ◘ Eastern Arborvitae
Plant community: Red Maple Swamp
Native region: Eastern North America
Height: 20′-40′
Spread: 10′-15′
Habitat: Grows in average, medium moisture, well-drained soils in full sun to part shade. Somewhat wide range of soil tolerance, but prefers moist, neutral to alkaline, well-drained loams (especially of some limestone content). Intolerant of dry conditions. Best in full sun, but generally appreciates some light afternoon shade in hot summer climates. Does not grow well in full shade or exposed, windy sites.
Hardiness zone: 2 to 7
Flowers: Has male pollen cones and female seed cones on the branchlets of the same tree. Cones bloom from late spring to early summer and are cross-pollinated by the wind. Male cones are about 2 mm long, rounded, and yellowish in color. Female cones 9-13 mm and are initially pink to purple, but become brown and woody at maturity later in the same year. They are ellipsoid in shape and have several pairs of overlapping scales that are ovate in shape. These scales spread apart to release their seeds from late summer into the fall. Each mature female cone has about 8 seeds (4 fertile scales with 2 seeds each).
Leaves: Scale-like, aromatic, yellow-green to green foliage appears in flattened sprays. In exposed sites, foliage may show some winter burn (turns yellow-brown).
Wildlife Benefits:
Birds such as the Ruffed Grouse, Pine Siskin, Common Redpoll, Slate-Colored Junco, and Tree Sparrow eat the seeds or cones. The Red Squirrel will eat the seeds and cones as well. White-Tailed Deer browse on the branchlets and twigs, and also find shelter within stands of Northern White Cedar during the winter. The Pileated Woodpecker may search for carpenter ants within the wood of older trees.
The dense branching habit and evergreen foliage provides good nesting habitat for migratory songbirds such as the Cape May Warbler, Blackburnian Warbler, and Golden-Crowned Kinglet. Other migratory songbirds that are attracted to this tree during the summer include the Swainson's Thrush, Northern Parula, Black-Throated Green Warbler, Black-and-White Warbler, Magnolia Warbler, and White-Throated Sparrow.
Sources:
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c246
http://www.illinoiswildflowers.info/trees/plants/white_cedar.html