According to observations of naturalists and beekeepers.
Where are you?
Scouler's willow is found primarily in the boreal forests of North America. It is widely distributed, occurring in Canada from the Yukon Territory south through British Columbia and east through Alberta, Saskatchewan and into Manitoba. In the United States, Scouler's willow occurs in Alaska, south through the western states and into Mexico in the mountains, and east to the Black Hills of South Dakota.
This plant is present in at least 18 states/provinces in this country.
Scouler's willow is generally a shrub, reaching 6 to 35 feet (2-10.6 m) in height. It occasionally grows as a tree and may reach 65 feet (20 m) in height. It is nonrhizomatous with a deep, extensive root system and may be multistemmed or have one main trunk with twigs spreading or ascending. It occurs in thickets and forests forming a tall shrub layer in young stands, but is intolerant of shade and can persist only under thin canopies. Beneath a tree canopy, Scouler's willow exhibits a tall, upright growth form, but if top-killed by disturbance it sprouts from the root crown creating a round growth form up to 16 feet (4.8 m) in diameter.
Scouler's willow has slender stems and branches reaching 4 to 8 inches (10-20 cm) in diameter at the base; smooth to flaky bark; and glabrous twigs. Leaves are glabrous to leathery, obovate to oblanceolate, and occasionally serrate. Twigs and leaf undersides of Scouler's willow are densely to thinly pubescent, with appressed, reddish hairs. Young twigs and vigorous shoots are often densely pubescent, while older stems are smooth. Stripped bark of Scouler's willow has a skunky odor.
A dioecious plant, Scouler's willow has large, single-scaled, floral winter buds, and lacks a terminal bud. Aments, expanding before or with leaves and quickly deciduous, are usually sessile or borne on a short spur shoot and flower profusely. Fruiting catkins are 0.8 to 2.4 inches long (2-6 cm) by 0.4 to 0.6 inches thick (1-1.5 cm) with dark floral bracts 4-5 mm long, one gland, and a capsule 5-8 mm long with dense, short hairs and a somewhat long beak.
Scouler's willow bud development begins in April, leafing out occurs in April and May, stem elongation occurs May through July, and leaf fall occurs in July through November. Earlier leaf fall is correlated with limited moisture availability. Flowering occurs in April through June, with fruit ripening and seed dispersal occurring in May through July.
Cercis orbiculata (aka: California redbud, Western redbud, Arizona redbud, Judas tree, Cercis occidentalis)
Rubus ursinus (aka: California blackberry, California dewberry, California grapeleaf dewberry, Douglasberry, Pacific blackberry)
Rubus spectabilis (aka: Salmonberry)
Aesculus californica (aka: California buckeye, Buckeye, Horsechestnut)
Salix lucida (aka: Shining willow, Greenleaf willow, Tail-leaf willow, Whiplash willow, Pacific willow, Lance-leaf willow, Longleaf willow, Red willow, Western shining willow)
Salix scouleriana (aka: Scouler's willow, Upland willow)
Acer circinatum (aka: Vine maple)
Malus fusca (aka: Oregon crab, Oregon crab apple, Pacific crab apple, Western crab apple)
Salix bebbiana (aka: Bebb willow, Beak willow, Beaked willow, Long-beaked willow, Diamond willow, Chaton, Petit Minou, Smooth Bebb willow)
Salix lemmonii (aka: Lemmon's willow, Lemmon willow)
Salix lutea (aka: Yellow willow)
Astragalus (aka: Milkvetch, Locoweed, Goat's-thorn)
Salix boothii (aka: Booth's willow)
Salix geyeriana (aka: Geyer willow, Silver willow)
Robinia pseudoacacia (aka: Black locust, False acacia, Yellow locust, White locust, Green locust, Post locust, Falsa acacia, Robinia)
Rhamnus cathartica (aka: Common buckthorn, European buckthorn, Dahurian buckthorn)
Rubus laciniatus (aka: Cutleaf blackberry, Evergreen blackberry, Slashed blackberry)
Rhus glabra (aka: Smooth sumac, Common sumac, Rocky Mountain sumac, Red sumac, Western sumac, White sumac)
Brassica napus (aka: Rapeseed)
Sinapis arvensis (aka: Charlock mustard, California rape, Charlock, Corn mustard, Canola, Kaber mustard, Rapeseed mustard)
Gleditsia triacanthos (aka: Honey locust, Honey shucks locust, Common honeylocust, Sweet bean locust)
Asclepias tuberosa (aka: Butterflyweed, Butterfly Milkweed, Orange Milkweed, Pleurisy Root, Chigger Flower, Canada root, Fluxroot, Indian paintbrush, Indian posy, Orange root, Orange Swallow-wort, Tuber root, Yellow milkweed, White-root, Windroot, Butterfly love)
Calendula officinalis (aka: Marigold, Calendula, Pot marigold, English marigold)
Prunus virginiana (aka: Chokecherry, Western chokecherry, Common chokecherry, Black chokecherry)
Salix brachycarpa (aka: Shortfruit willow, Barren-ground willow, Small-fruit sand dune willow, Small-fruit willow)
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)
Rubus parviflorus (aka: Thimbleberry, Western thimbleberry)
Amorpha fruticosa (aka: Desert false indigo, False indigo-bush, Bastard indigobush, Indigo Bush)
Brassica rapa (aka: Field mustard, Common mustard, Wild mustard, Wild turnip, Forage turnip, Wild rutabaga, Birdsrape mustard, Rape mustard)
Salix planifolia (aka: Diamondleaf willow, Planeleaf willow)
Rubus armeniacus (aka: Himalayan blackberry, Rubus discolor, Rubus procerus)
Salsola kali (aka: Russian thistle, Tumbleweed, Prickly saltwort)
Cucumis melo (aka: Cantaloupe, Rockmelon, Sweet melon, Spanspek, Honeydew melon, Honeymelon, Crenshaw, Casaba)
Citrullus lanatus (aka: Watermelon)
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)
Borago officinalis (aka: Borage, Starflower, Common borage, Cool-tankard, Tailwort)