Himalayan blackberry
Rubus armeniacus (formerly discolor)
Family: Rosaceae.
Type: Semi-deciduous ground cover to shrub.
Branching: Alternate.
Leaves: Palmately compound leaves, which tend to have five leaflets per leaf; this is not a reliable distinguishing characteristic, however. Leaves are never hirsute.
Twig: Stems are strongly ridged, and are green to purple (darker than the pale colors of the trailing blackberry). As with the trailing blackberry, roots are perennial, but canes are biennial. Prickles are much stouter, thicker, and sparser than in the trailing blackberry.
Fruit & Flower: Fruit is a blackberry, a drupe; the berry of the Himalayan blackberry tends to be bigger, juicier and sweeter than those of the trailing blackberry.
Miscellaneous: The Himalayan blackberry is actually from Armenia, and was introduced to the Himalayas for fruit production, and then subsequently introduced from there to the United States. It is therefore non-native; invasive species are common in riparian areas because of the high disturbance and the easy access to water and nutrients. Like trailing blackberry, Himalayan blackberry spreads asexually because its canes are stolons (also known as runners): they can take root where they touch down.