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	©Copyright 1993 by the Regents of the University of California Print edition is available from the University of California Press

	The second edition of The Jepson Manual (2012) is available from the University of California Press
	See also the Jepson eFlora, which parallels the Second Edition

SALICACEAE

WILLOW FAMILY

Shrub, tree, generally dioecious (rarely monoecious)
Stem: trunk < 40 m; wood soft; bark smooth, bitter; buds scaly
Leaves simple, alternate, deciduous; stipules generally deciduous, often large
Inflorescence: catkin, generally appearing before leaves; each flower subtended by disk or 1–2 nectary glands and 1 bract
Flower: perianth 0
Staminate flower: stamens 1–many
Pistillate flower: pistil 1, ovary superior, chamber 1, stigma lobes 2–4
Seeds many; hairs fine, white, cottony
Fruit: capsule; valves 2–4
Genera in family: 2 genera, 340 species: generally temp (except Australia, Malay Archipelago) moist places; many cultivated. Hybridization common; identification often difficult. Family description, key to genera by John O. Sawyer, Jr.

SALIX

WILLOW

George W. Argus

Shrub, tree, dioecious; bud scale 1, not sticky, margins generally fused (or free, overlapping)
Stem: twigs generally flexible and not glaucous
Leaf: blade linear to widely obovate, entire to toothed, generally ± hairy
Inflorescence: dense catkin emerging before, with, or after leaves, sessile or on a short leafy shoot; bract subtending each flower
Flower: perianth 0
Staminate flower: stamens 1–8
Pistillate flower: ovary stalked or sessile, style 1 or 0, stigmas 2, each sometimes 2-lobed; nectaries 1–several, generally rod-like, generally between inflorescence axis and flower
Fruit: valves 2
Species in genus: ± 400 species: ± worldwide, especially n temp, arctic
Etymology: (Latin: ancient name)
Reference: [Argus 1986 Syst Bot Monog 9:1–170; Dorn 1976 Canad J Bot 54:2769–2789]
Difficult, highly variable. Not all specimens will key easily; sprout shoots and other extreme forms are not included in keys, may require field comparison for identification. Studies of variation, hybridization needed.

Native

S. boothii Dorn

BOOTH'S WILLOW

Shrub < 6 m
Stem: twigs gray- to red-brown, glabrous or shaggy-hairy
Leaves: petiole generally with glands; young leaves shaggy-hairy; mature blade 26–102 mm, lanceolate to widely elliptic, acute (base rounded to acute), entire to finely serrate, soft-shaggy-hairy, becoming glabrous, shiny above, not glaucous below
Inflorescence appearing before or with leaves, 10–70 mm, sessile or on leafy shoots < 15 mm (margins of shoot-leaves gland-dotted or finely serrate); flower bract generally dark brown, hairs wavy
Staminate flower: stamens 2
Pistillate flower: ovary glabrous, style 0.3–1 mm, stalk 0.5–2.5 mm
Chromosomes: 2n=76
Ecology: Uncommon. Wet subalpine meadows, shores
Elevation: 1700–3200 m.
Bioregional distribution: Klamath Ranges, High Cascade Range, n High Sierra Nevada, Warner Mountains, White and Inyo Mountains
Distribution outside California: to w Canada, Colorado
Flowering time: Jun–Jul
Synonyms: S. pseudocordata Andersson; S. myrtillifolia Andersson misapplied