Description: This woody vine is up to 10-20' long; it climbs over adjacent shrubs or the lower branches of trees using tendrils. The woody stems are mostly green and round; lower stems are heavily armed with stout straight spines and stiff bristles, while upper stems have few, if any, spines. These spines and bristles become dark brown or black with age. The alternate leaves are up to 5" long and 4" across; they are oval to broadly ovate, smooth along the margins, and hairless. Their margins may have minute teeth, but this is easier to see with a 10x hand lens. Each leaf has 3-7 parallel veins; its upper surface is green, while the lower surface is light green (but not glaucous). At the base of each leaf, there is a slender petiole and a pair of curly tendrils. These tendrils are initially green, but they later become rather stiff and brown.
Occasionally, individual umbels of flowers will be produced from the axils of the upper leaves. The peduncles (stalks) of these umbels are longer than the petioles of the leaves. Each umbel has 8-30 flowers and spans about 2-3" across. Because Smilax spp. are dioecious, a vine will produce either all staminate flowers or all pistillate flowers; perfect flowers are rarely produced. Each staminate (male) flower is about ¼" across; it consists of 6 yellowish or greyish green tepals and 6 stamens. Each pistillate (female) flower is about ¼" across; it consists of 6 yellowish or greyish green tepals, a single ovary, and a short tripartite style. The ovary is ovoid, shiny, and green. The blooming period occurs from late spring to early summer and lasts about 2 weeks. There is no noticeable floral scent. The staminate flowers quickly wither away after blooming. The pistillate flowers develop into fleshy berries. Each berry is about ¼" across, dark blue or black, and contains 1-3 seeds. The leaves are deciduous and fall to the ground during the fall. The root system has short stout rhizomes. This woody vine spreads vegetatively by rhizomes or by reseeding itself.
Cultivation:
The
preference is light shade to partial sun, moist to mesic conditions,
and a fertile loamy soil.
Range & Habitat:
The native Bristly Greenbrier is a common woody vine that has been
observed in
nearly all counties of Illinois (see Distribution
Map); it probably occurs in the remaining counties as well.
Habitats include moist to mesic woodlands, openings in wooded areas,
woodland borders, thickets, and powerline clearances in wooded areas.
Faunal
Associations:
Various bees and flies visit the flowers for nectar or pollen. The
caterpillars of several moths feed on Smilax spp.,
including Phosophila turbulenta (Turbulent
Phosphila), Phosophila miselioides (Spotted
Phosphila), and Phyprosopus callitrichoides
(Curved-Lined Owlet). The berries are eaten by both upland gamebirds
and various songbirds during the fall and winter (see Bird
Table). Black Bears, Raccoons, and other mammals also eat the
berries. White-Tailed Deer occasionally browse on the foliage and stems.
Photographic Location:
Underneath a tree near a powerline clearance at Busey Woods in Urbana,
Illinois.
Comments:
The species in the Smilax genus fall into two
groups: woody vines with thorns, and herbaceous vines or shrubs without
spines. Bristly Greenbrier is a typical example of the former group,
except that it is more ferociously armed than most Greenbriers. Species
in the latter group are called Carrion Flowers. Greenbriers are unusual
among woody vines because their branches are green, even during the
winter. Bristly Greenbrier can be distinguished from other Greenbriers
by the stout straight spines and stiff bristles on its lower branches.
Other Greenbriers in Illinois have stout curved spines without stiff
bristles, and they are restricted to the southern part of the state.
Sometimes Bristly Greenbrier is referred to by the scientific name Smilax
tamnoides hispida.