Silky Dogwood is a plant of moist places, that grows from 3 to 10 feet high as a multi-stemmed shrub, not as a small tree. Bark is reddish-purple on young thicker stems, turning brown with age. Twigs are grayish-green when new, then reddish-purple with silky hair and with buds that are hairy, pointed and appressed to the stem. The pith of older twigs is brown.
The leaves are opposite, entire, ovate to oval shape, 2 - 4 inches long, stalked, pale beneath and tapered at both ends. Leaf veins curve toward the tip. Stalks have fine hair.
The inflorescence is a flat branched cluster (a cyme ) about 2 inches wide.
The flowers are perfect, white, 4-part, 1/4 inch wide, with 4 white spreading lance-shaped petals, 4 stamens that arise alternate with the petals on long filaments with yellow anthers and a pistil with a single style that has a yellow-green knob-like tip. The green calyx is quite small. Flower stalks and the stalk of the cyme may have fine hair.
Fruit: The fruit is a 1/3 inch diameter round drupe containing one seed. Drupes are green initially and mature to a dark blue in late August.
Varieties: There are 2 known subspecies and one variety: var. schuetzeana, which is considered the species native to Minnesota; and then ssp. obliqua. Some authorities, such as USDA, consider both of these as forms and synonyms of Cornus obliqua. The second subspecies is ssp. amomum, a form of Cornus amomum. So we have two main scientific names that use the common name of 'Silky Dogwood'. Minnesota authorities, the DNR and the U of M Herbarium, simply list it (the species native to Minnesota) as C. amomum var. schuetzeana (Silky Dogwood). Eloise Butler also used C. amomum. The details between the variety differences are probably not pertinent to this general discussion of the species.
Habitat: Silky Dogwood grows in moist soils from a shallow spreading root system. Full sun is preferred but it will tolerate partial shade. A good specimen grows at the intersection of Lady's-slipper Lane and Geranium Path at the far end of the Woodland Garden. You will find it's branches intertwined with the Ninebark that grows next to it.
Names: The genus, Cornus, is from the Latin cormu which refers to a 'horn'. Most references believe that name was applied as a reference to the density of the wood of this genus, which also includes the boxwoods. Dogwood is very dense and was once used for loom shuttles. Cornus is also the old Latin name for the cornelian cherry, Cornus mas. The species obliqua, which means 'lopsided' or 'oblique' and refers to the drupe's stone pit which is of a lopsided shape, narrowed and pointed at the base. Other dogwoods have more round stones. The species name amomum, is from the Greek name amomom, referring to a spice plant. The author name for the plant classification - "Mill." is for Philip Miller, Scottish botanist (1691-1771) who was chief gardener at the Chelsea Physic Garden and wrote "The Gardener's Dictionary". For C. obliqua - ‘Raf.’ is for Constantine Samuel Rafinesque, (1783-1840), European polymath who traveled in the United States, lived here many years, collected specimens, and published over 6,700 binomial names for plants. He applied to be botanist on the Lewis & Clark expedition but Jefferson turned him down in favor of training Lewis to be botanist and saving the expense of another person.
Comparisons: There are four Dogwoods in the Garden. All have similar looking flowers. An identification key is presented below the photos.
Above:The individual flowers have 4 spreading petals with the stamens rising opposite them. The green calyx of the flower head is very small.
Below: The upper side of the leaf - veins curve toward the tip. The underside of the leaf is paler color, often with very fine hair.
Below: 1st photo - Flower cluster of late-June. 2nd photo - Green fruit of early July.
Below: 1st photo - Fruit of early August. 2nd photo - Mature blue fruit of late August.
Below: 1st photo - Bark on medium age stems is reddish-purple. 2nd & 3rd photos - Twigs are grayish-green when new first year, then reddish-purple with silky hair and with buds that are hairy, pointed and lateral buds appressed to the stem.
|Dogwood Species||C. racemosa||C. amomum (C. obliqua)||C. alternifolia||C. sericea|
|Common Name||Gray Dogwood||Silky Dogwood
|Pagoda Dogwood||Red Osier Dogwood|
|Alternate Names||Panicled Dogwood||Silky Dogwood||Alternate-leaf Dogwood|
|Height & Size||to 6' forming a thicket||3 to10' shrub||to 30' small tree||to 9' in thickets|
|Flowers||All four dogwoods have small 4-part white flowers that are borne in branching clusters.|
|Flower cluster||nearly as high as wide and NOT flat topped||Flat-topped, flower stalks silky (hairy)||Flat-topped, mostly at the ends of branches||Flat-topped|
|Bloom period (typical - varies with season)||mid- to late June||late May to June||Late May to mid-June||Early May onwards.|
|Leaves||Opposite, entire, stalked, oval to lance shape, pale under, veins curve to tip.||Opposite, entire, stalked, ovate to oval shape, taper at both ends, pale under, veins curve to tip.||Alternate, entire, stalked, broadly oval, rounded base, taper at tip. Glossy green above, form clusters at end of branches. 'Quilt-like' surface.||Opposite, entire, stalked, oval to lance shaped, 5 to 7 pairs of veins, whitish under.|
|Branches||Gray, smooth, some wart-ish bumps||Purplish||Greenish, smooth. Twigs red.||Younger branches reddish in fall, winter and spring|
|Mature Fruit||White with conspicuous red stalks||dark blue||dark blue||white to lead|
Notes: Eloise Butler originally introduced Silky Dogwood to the Garden on April 26, 1913 with plants obtained from Kelsey's Nursery in North Carolina. Her reference was to the scientific name C. amomum which in var. schuetzeana, is considered the species native to Minnesota. It is known in both Minnesota and North Carolina. This species was not listed on Martha Crone's 1951 Plant Census. Native to Minnesota in the east central counties and in the SE. In North America it grows from the central U.S. (Dakotas to Oklahoma) eastward to the coast, but no further south than Kentucky and Virginia. In Canada it is found from Ontario eastward.
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"