This page is based on the 1993 Jepson Manual.
Please see the Jepson eFlora for up-to-date information about California vascular plants.
|Jepson Flora Project: Jepson Interchange|
|TREATMENT FROM THE JEPSON MANUAL||
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Jepson Interchange (more information)
©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|
Tree, shrub, monoecious
Stem: trunk < 35 m; bark ± smooth; lenticels present
Leaves simple, alternate, petioled, deciduous; stipules deciduous; blade ovate to elliptic, generally serrate, ± doubly so
Inflorescence: catkin, generally appearing before leaves, often clustered; bracts each subtending 23 flowers and 36 bractlets
Staminate inflorescence pendent, ± elongate
Pistillate inflorescence pendent or erect, developing variously in fruit (see key to genera)
Staminate flower: sepals 04, minute; petals 0; stamens 110; pistil vestigial or 0
Pistillate flower: sepals 04; petals 0; stamens 0; pistil 1, ovary inferior, chambers 2, each 1-ovuled, stigmas 2
Fruit: nut or nutlet, sometimes winged, subtended or enclosed by 12 bracts
Genera in family: 6 genera, 105 species: generally n hemisphere; some cultivated.
Stem: trunk < 30 m; bark smooth or scaly, aromatic, often peeling in thin layers; twigs puberulent, glandular, or both; lenticels prominent; winter buds sessile, 3-scaled
Leaf glandular-hairy; blade 25 cm, widely elliptic, base ± truncate to tapered
Staminate inflorescence 27 cm; bracts each subtending 3 flowers and 3 bractlets
Pistillate inflorescence 23 cm; bracts each subtending 3 flowers and 3 bractlets
Staminate flower: sepals 4; stamens 2
Pistillate flower: sepals 0
Fruits many, in a non-cone-like catkin, winged; bracts lobed, papery, released with but not attached to fruit
Species in genus: 50 species: circumboreal
Etymology: (Latin: birch)
Important wildlife food; wood used for interior finishing; many species cultivated.
Stem: trunks < 10 m; bark black, red-brown, not peeling; twigs with large resin glands, hairy
Leaf: petiole < 15 mm, hairy; blade 25 cm, widely ovate, thin, glands especially on upper surface, base ± truncate to tapered, tip acute, margin doubly serrate except at base
Pistillate inflorescence 35 cm; bract fringed with hairs
Ecology: Streamsides, springs
Elevation: 6002500 m.
Bioregional distribution: Klamath Ranges, High Cascade Range, High Sierra Nevada, Great Basin Floristic Province, Desert Mountains
Distribution outside California: scattered in w N.America
Flowering time: AprMay
Horticultural information: WET: 1, 2, 3, 4, 5, 6, 7, 9, 10, 14, 15, 16, 17, &SHD: 18, 19, 20, 21, 22, 23, 24; STBL.
|YOU CAN HELP US make sure that our distributional information is correct and current. If you know that a plant occurs in a wild, reproducing state in a Jepson bioregion NOT highlighted on the map, please contact us with that information. Please realize that we cannot incorporate range extensions without access to a voucher specimen, which should (ultimately) be deposited in an herbarium. You can send the pressed, dried collection (with complete locality information indicated) to us (e-mail us for details) or refer us to an accessioned herbarium specimen. Non-occurrence of a plant in an indicated area is difficult to document, but we will especially value your input on those types of possible errors (see automatic conversion of distribution data to maps).|