4. Rubus phoenicolasius Maxim. (wineberry)

Map 2502

Canes to 400 cm long, erect, to 200 cm tall when young, but ultimately arching and often rooting at the tips. Primocanes dark purple, 4–7 mm in diameter, densely covered with stiff purple hairs, many gland-tipped, and occasional prickles. Prickles moderate, 1.0–2.3 prickles per cm of cane, slender and straight, 5–8 mm long. Petioles densely covered with stiff purple hairs, many gland-tipped, and downward-curved prickles to 3 mm long. Stipules 5–14 mm long, linear, glandular. Primocane leaves with 3 leaflets, the margins doubly toothed, the upper surface appearing wrinkled (having deeply impressed veins), grayish and hairy, the undersurface densely white-felted but with dark red veins bearing gland-tipped hairs. Central primocane leaflets 6.5–11.5 cm long, 5.5–12.0 cm wide, broadly ovate, often 3-lobed, cordate to nearly truncate at the base, abruptly tapered to a short, sharply pointed tip, the leaflet stalk about 1/4–2/5 as long as the leaflet blade; lateral leaflets much smaller, oblong or oval, nearly sessile. Inflorescences paniculate, 30–42 cm long, with 6–22 flowers and 6–8 leafy bracts, these mostly with 3 leaflets; flower and inflorescence stalks densely covered with stiff hairs, many gland-tipped, inflorescence stalks also bearing slender, straight prickles. Sepals 7–8 mm long, 2.5–3.5 mm wide, lanceolate, the outer surface with gland-tipped hairs. Petals 4–5 mm long, spatulate, minutely toothed near the tip, white to pale pink. Fruits 10–15 mm long, 10–15 mm wide, hemispheric, enclosed in the calyx when young, orangish red. 2n=14. May–June.

Introduced, uncommon and sporadic south of the Missouri River (native of Asia; naturalized in the eastern U.S.). Bottomland forests, disturbed openings of mesic upland forests, and bases and ledges of bluffs; also railroads and roadsides.

Although it was first-collected in 1949 in Cape Girardeau County, R. phoenicolasius was not included in Steyermark’s (1963) treatment of the genus in Missouri. The species is first-reported from Missouri in the present account. In some other states, it is considered an invasive exotic.