Cornus sericea

Redosier dogwood

Cornaceae

The Basics

Taxonomy: Kingdom - Plantae (plants). Subkingdom - Tracheobionta (vascular plants). Superdivision - Spermatophyta (seed plants). Division - Magnoliophyta (flowering plants). Class - Magnoliopsida (dicotyledons). Subclass - Rosidae. Order - Cornales. Family - Cornaceae (dogwood). Genus - Cornus L. Species - Cornus sericea L.

Ecology: Redosier dogwood is shade tolerant but generally grows best at intermediate to high light levels. Cover and size of redosier dogwood are often greater in open stands or canopy gaps than beneath heavily shaded canopies, but redosier dogwood persists and may be abundant in dense shade. Redosier dogwood is typically present throughout all stages of succession, but abundance is often greater in earlier than later stages. Similarly, redosier dogwood occupies open sites and occurs beneath closed canopies, but abundance is typically greater in sun than shade. Redosier dogwood tolerates disturbance and generally appears early in postdisturbance succession of shrublands, floodplains, forests, and old fields. Abundance of redosier dogwood is often greater many years after disturbance than immediately following disturbance. Redosier dogwood is common on the edges of lakes, ponds, within wetlands, and along streams. Not as tolerant of long-term root saturation as are some other shrubs, dogwood seems to prefer wetland margins where soils are nitrogen-rich, saturated, and shallowly inundated in the spring, and may be completely dry by late summer. It is tolerant of fluctuating water tables. The “osier” in redosier dogwood is derived from French, meaning “willow-like”; it is often called red willow because of its red stems.

Identification

Redosier dogwood is a multistemmed, erect to loosely spreading, deciduous shrub that grows 1-6 m tall and often as wide. Shrubs often form clumps or dense thickets by stolons and prostrate, rooting stems and lower branches. Redosier dogwood branches are opposite, and twigs are generally less than 2 mm in diameter. Growth form and size of redosier dogwood are highly variable and many local forms exist. While most often a multibranched shrub, in areas with a dense grass layer redosier dogwood may be restricted to a single main stem. Shrubs growing in full sun are typically dense and compact, with many lateral branches; shrubs growing in shade are typically open and sprawling, with few branches. Redosier dogwood leaves growing in the shade are generally larger and thinner than those growing in full sun.

Habit: Shrub generally 1.5--4 m. Stem: branches +- red to purple, +- glabrous to minute-strigose, in age gray-green, generally glabrous. Leaf: blade generally 5--10 cm, lanceolate to ovate or elliptic, paler abaxially, veins 4--7 pairs. Inflorescence: cyme, strigose; bracts 0. Flower: petals 2--4.5 mm; style 1--3 mm. Fruit: 7--9 mm, white to cream; stone smooth or 3-ridged on faces, furrowed on sides.

Threats

In the YFDP: Redosier dogwood primarily grows in riparian areas, which served as fire refugia during the 2013 fire.

Fire effects: Most fires only top-kill redosier dogwood shrubs. Mortality is likely restricted to severely burned sites where duff and litter are consumed and upper soil layers experience extended heating. Redosier dogwood seeds appear to be heat tolerant, and seedlings were reported within a year of burning in a riparian site in the northern Sierra Nevada.

Reproduction

Pollination and breeding system - Redosier dogwood produces perfect flowers that are obligate outcrossing and insect-pollinated. Observations suggest that bumblebees may be the most frequent visitors to redosier dogwood flowers, but many bee, fly, and butterfly visitors have been observed.

Seed dispersal - Redosier dogwood seeds are primarily dispersed by birds and mammals. Many bird species eat redosier dogwood fruits and likely disperse its seed. Redosier dogwood seeds were not harmed by consumption by bears, and seeds in bear feces may present an opportunity for secondary dispersal by rodents.

Seedling establishment and plant growth - Redosier dogwood seedlings were commonly found in riparian and forested habitats. Seedlings occurred in open to closed-canopy conditions at riparian sites and disturbed sites. The primary root growth of seedlings is vigorous, and seedlings can typically sprout after aboveground damage.

Vegetative regeneration - Vegetative spread and regeneration are important to the persistence of redosier dogwood. Redosier dogwood spreads and regenerates vegetatively by stolons, layering, and root crown sprouts. Shrub size commonly increases through the rooting of prostrate stems and lower branches.

Species Distribution

Citation

USDA Plants Database
USDA, NRCS. 2016. The PLANTS Database. National Plant Data Team, Greensboro, NC 27401-4901 USA.

USFS Plant Database
Habeck, R. J. 1992. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.

The Jepson Herbarium
The Jepson Manual: Vascular Plants of California. B.G. Baldwin, D.H. Goldman, D.J. Keil, R. Patterson, T.J. Rosatti, and D.H. Wilken [editors]. 2012. 2nd edition, thoroughly revised and expanded. University of California Press, Berkeley, CA.

Burke Museum of Natural History and Culture
Burke Museum. 2016 [Online]. University of Washington.
Photo credit: Ben Legler 2005