The pagoda dogwood (Cornus alternifolia) is also known as the blue dogwood, green osier, pagoda-cornel, and alternate-leaf dogwood. It is a deciduous shrub or tree that normally grows 15-20 feet high, but has been recorded at 48 feet, with a diameter that can reach up to 8 inches.
Habitat: Found on moist upland woods. Located in the northeast two-thirds of the state.
Hardiness: Zones 4 through 7
Growth Rate: Fast
Mature Shape: Round; horizontal branching
Height: 15-30 feet
Width: 15-30 feet
Site Requirements: Cool, moist, acidic soil and partial shade is ideal, but full sun is acceptable
Flowering Dates: May - July
Seed Dispersal Dates: July - September
Seed Bearing Age: 2-6 years
Seed Bearing Frequency: Yearly
Seed Stratification: Warm stratification for 2 months at 68°F to 85°F followed by pre-chilling for 2 months at 40°F
The leaves measure 3 to 5 inches in length, and 2 1/2 to 3 1/2 inches in width. Each leaf is dark green on top, and paler or whitened underneath, simple, oval to broadly ovate, entire with with wavy margins, alternate and also cluster at the tips of each branchlet. Petioles are 1 to 2 inches and tinged reddish. The fruits are drupes, 3/4 inches in diameter, dark blue-black, and in loose flat-topped clusters. The fruits can be seen July through August, and in some areas as late as October.
The wood is usually not used for commercial purposes due to the small size of the tree. Pagoda dogwood is usually seen as an ornamental tree and used to attract backyard wildlife as many bird species also enjoy the fruit.
In its natural habitat, the pagoda dogwood is found in the understory of cool, moist upland woods, seen often in ravines, bordering swamps, and along wooded stream banks. Its range is from New Brunswick to Minnesota, south to northern Georgia and Alabama, and can be found in Iowa in 2/3 of the state's northeast.