ANNAPOLIS, MD (September 15, 2006) - Wineberry (Rubus phoenicolasius), a cousin of Raspberries, is one of a number
of species and hybrids in a diverse genus. The plant was introduced into the United
States from Asia in 1890 as breeding stock for Rubus cultivars and is still used today
by berry breeders. Although it is a useful plant when contained, wineberry is
considered a pest now that it has escaped into agricultural and natural ecosystems.
Wineberry has naturalized from New England and eastern Canada south to North Carolina
and west to Michigan and Tennessee. It is found in forest, field, stream, and wetland
edge habitats and in open woods and light gaps, preferring moist soils. It is
considered an invasive plant in Maryland, as well as in neighboring Virginia, West
Virginia, Pennsylvania, and the District of Columbia. Though it is past fruiting
season, the red-bristled canes of Wineberry are distinctive this time of year, so
MISC has named it September’s Invader of the Month.
Like other brambles in its genus, wineberry forms a clump of arching canes that
may reach nine feet in length. Canes may stay vertical or bend toward the earth,
rooting again where they touch and producing more canes that can form dense thickets.
The species’ tongue-twisting scientific name literally means “blackberry with purple
hairs,” an apt, though not entirely accurate description. Younger canes in some
patches may maintain a greenish color, but mature plants have canes that are covered
with distinctive glandular reddish or brown hairs and weak spines. The hairs give
the canes a soft reddish color when seen from a distance.
Wineberry leaves are compound, alternate along the stem, and divided into three
heart-shaped leaflets with serrated edges, purplish veins, and silvery white hairs
on the leaflets’ undersides. Small green flowers with white petals and reddish hairs
occur in spring. The very edible raspberry-like fruit ripens to a bright, clear red
in June and July.
Wineberry’s rapid growth poses a threat to native plants by creating dense patches
that crowd out desirable species. It spreads not only vegetatively by tip-rooting
but also by seeds transported by birds and mammals, including human beings, who seek
out the delicious fruits. Wineberry is difficult to control and should never be
deliberately planted. Small infestations can be handled by pulling individual plants—if
the soil is moist—or digging them out with a shovel or 4-pronged spading fork. Where
accessible, canes can be mowed with brush-type equipment. In some areas workers may
need to use brush-blade power tools. In either case, low re-growth can be treated with
foliar applications of glyphosate or triclopyr herbicides (e. g., Roundup, Rodeo,
Garlon 3A, or Brush B Gon).
For more information about other Invasive Species of Concern,
visit www.mdinvasivesp.org or call the
Maryland Department of Agriculture at 410-841-5920.
photos available electronically on request.