According to observations of naturalists and beekeepers.
Where are you?
30 kilograms per ha
SOURCE FOR HONEY BEES:
Major in some areas
California blackberry grows from British Columbia to northern California and eastward to central Idaho. It is particularly common from the Cascades to the Pacific Coast. California blackberry extends through southern California into Mexico. The subspecies macropetalus occurs from British Columbia and Idaho southward into northern California.
This plant is present in at least 6 states/provinces in this country.
Rubus ursinus is a wide, mounding shrub or vine, growing to 2–5 feet (0.61–1.52 m) high, and more than 6 feet (1.8 m) wide. The prickly branches can take root if they touch soil, thus enabling the plant to spread vegetatively and form larger clonal colonies. Leaves usually have 3 leaflets but sometimes 5 or only 1, and are deciduous. The plant is dioecious, with male and female plants on separate plants, also unusual for the genus. As with other Rubus, the canes are typically vegetative the first year and reproductive in the second. Flowers are white with narrower petals than most related species and have a fragrance. The sweet, very aromatic, edible fruits are a dark purple, dark red, or black and up to 2 centimeters (0.8 inches) in length.
Seasonal development of the California blackberry varies according to geographic and climatic factors.
Flowering Time: Late Spring, Early Summer.
Rubus ursinus (aka: California blackberry, California dewberry, California grapeleaf dewberry, Douglasberry, Pacific blackberry)
Rubus laciniatus (aka: Cutleaf blackberry, Evergreen blackberry, Slashed blackberry)
Salix lutea (aka: Yellow willow)
Salix geyeriana (aka: Geyer willow, Silver willow)
Allium schoenoprasum (aka: Chives)
Brassica napus (aka: Rapeseed)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Cirsium arvense (aka: Creeping Thistle, Canada thistle, Field thistle, California thistle, Lettuce from hell thistle, Corn thistle, Cursed thistle, Green thistle, Hard thistle, Perennial thistle, Prickly thistle, Small-flowered thistle, Way thistle, Stinger-needles)
Salix brachycarpa (aka: Shortfruit willow, Barren-ground willow, Small-fruit sand dune willow, Small-fruit willow)
Rubus parviflorus (aka: Thimbleberry, Western thimbleberry)
Rubus armeniacus (aka: Himalayan blackberry, Rubus discolor, Rubus procerus)
Rubus idaeus (aka: Raspberry, Black-haired red raspberry, Brilliant red raspberry, American red raspberry, Red raspberry, Smoothleaf red raspberry, Wild raspberry, Wild red raspberry, Grayleaf raspberry)
Echium vulgare (aka: Viper's bugloss, Blueweed, Blue thistle)
Brassica rapa (aka: Field mustard, Common mustard, Wild mustard, Wild turnip, Forage turnip, Wild rutabaga, Birdsrape mustard, Rape mustard)
Asclepias syriaca (aka: Сommon milkweed, Butterfly flower, Silkweed, Silky swallow-wort, Virginia silkweed)
Agastache foeniculum (aka: Giant hyssop, Blue giant hyssop, Anise hyssop, Fragrant giant hyssop, Lavender giant hyssop)
Chamaenerion angustifolium (aka: Fireweed, Great willowherb, Rosebay willowherb, Saint Anthony's Laurel, French-willow)
Borago officinalis (aka: Borage, Starflower, Common borage, Cool-tankard, Tailwort)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Hyssopus officinalis (aka: Hyssop)