Rubus ursinus
Common name: 
Trailing Blackberry
Western Blackberry
California Blackberry
RU-bus ur-si-NUS
Native to (or naturalized in) Oregon: 
  • Evergreen, semi-evergreen, shrub, low-growing, mound forming, climbing, brown, slender tailing stems grow to 10-20 ft (3-6 m) in length, may root where nodes touch the soil, young stems are greenish, pubescent and erect, but arch as they lengthen, stem densely covered with straight prickles ("thorns").  Leaves alternate, compound, 3 leaflets, sometimes 5, upper leaves may be simple, leaflets broad ovate, rounded at base, lobed and coarsely doubly serrate, 4-7.5 cm long, dark green above and paler and hairy below, rachis and petiole armed.  In the first year stems (primocanes) produce only leaves, in the second year lateral branches (floricanes) develop from axillary buds of primocanes and form both leaves and flowers.  Mostly dioecious (male and female plants), flowers white to pink, in pubescent and prickly clusters (corymbs), petals of male flowers about 10 mm long, those of female flowers 6-8 mm long.  Fruit black, usually oblong, 1-2 cm long, sweet and succulent at maturity.  When picked the berry remains attached to the central core (torus).
  • Sun or shade
  • Hardy to USDA Zone 3   Native range from British Columbia to northern California, and eastward to central Idaho, common from the Cascades to the Pacific Coast, the range extends through southern California into Mexico.  Often found in moist and shaded places, shrubland, stream sides, disturbed areas, and canyons below 3000 ft.
  • ursinus: "a bear," referring to one of a bear's favorite foods, the fruit.
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  • plant habit, stems (canes)

    plant habit, stems (canes)

  • leaf


  • stems and leaves

    stems and leaves

  • stems


  • flowers


  • plant habit, fruiting

    plant habit, fruiting

  • leaves and ripening fruit

    leaves and ripening fruit

  • leaves and ripening fruit

    leaves and ripening fruit