Jepson Herbarium
The University and Jepson Herbaria
University of California, Berkeley
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Jepson Herbarium
The University and Jepson Herbaria
University of California, Berkeley
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Only vascular plants are treated in The Jepson eFlora. Vascular plants are a monophyletic group or clade that includes (1) Lycophytes (often superficially moss-like but with thicker scale-like leaves and axillary sporangia that are often borne in cones), (2) Ferns (most with sporangia borne on abaxial leaf surfaces, a few with sporangia on modified leaf segments or in hard sporangium cases), and Equisetum, with whorled scale leaves and sporangia grouped in terminal cones, (3) Gymnosperms (with seeds generally produced in cones of various forms), and (4) flowering plants (with seeds developing in ovaries of flowers). Flowering plants in California include five clades: Nymphaeales, Magnoliids, Ceratophyllales, Eudicots, and Monocots (see back inside cover). Unlike all other organisms, vascular plants have true roots, stems, and leaves, with water- and nutrient-conducting (vascular) tissues that also provide structural support.
In terrestrial (and aquatic) environments, true mosses and leafy liverworts may appear superficially similar to vascular plants, but their minute leaves are filmy (generally only 1 cell layer in thickness), and their delicate, usually short stems are attached to soil or other substrate by fragile filaments of 1 or more cells (rhizoids) that lack conducting tissue. Mosses, the most diverse land plants in California other than vascular plants, have alternate, closely overlapping, scale-like or narrowly linear leaves and produce solitary sporangia (generally finely stalked) at the tips of leafy shoots. Some freshwater liverworts can be confused with free-floating vascular plants that lack clearly differentiated stems and leaves, but the liverworts can be recognized by their forking body plan or forked grooves on their upper surface.
Although in aquatic environments an emergent habit distinguishes vascular plants from other aquatics, potential for confusion of vascular plants with organisms other than mosses and liverworts in fully submersed settings warrants attention. In particular, some marine algae, such as kelps and rockweeds, appear superficially similar to vascular plants because of leaf-like, stem-like, and root-like (holdfast) structures. These algae, however, have accessory pigments ranging in color from olive-green to reddish or brownish that distinguish them from marine vascular plants, which are grass-green in color. Some of these algae have gas-filled floats, which are not found in marine vascular plants, and all of them are somewhat rubbery in texture, in contrast to the papery texture of marine vascular plants. Green alga e are similar in color to vascular plants; of these, charophytes, with a central axis and whorled, cylindric branches (but no leaves) are most readily confused with vascular plants.
Keys in the Jepson eFlora, are based primarily on structures associated with sexual reproduction (e.g., sporangia, cones, flowers, fruits). The eFlora does not provide a means for keying terrestrial vascular plants that are in strictly vegetative condition. For aquatic vascular plants, some of which reproduce mostly by vegetative means, a key is provided that allows identification using only vegetative characteristics. A key is also provided for identification of the few species in which tiny bulblets (small bulbs or corms) take the places of flowers in modified inflorescences or inflorescence-like clusters.
— Scientific Editor: Bruce G. Baldwin1. Specimens available for examination without flowers, these either not present on the specimen or not produced at all
2' Bulblets 03. Sporangia,sporangiumcases, seeds, cones, or cone-like structures 0 or not readily apparent [plants in strictly vegetative condition]In non-seed plants, a case or sac in which spores are produced, and from which they are released.
4' Plant terrestrial [Note: terrestrial plants in strictly vegetative condition cannot be identified with this key]3' Sporangia,sporangiumcases, seeds, cones, or cone-like structures present5. Herbs reproducing by spores released directly from sporangia, the sporangia variously located [on abaxialleafface, in stalked cluster arising fromOrgan arising from a stem, generally composed of a stalk (petiole) and a flat, expanded, green, photosynthetic area (blade); distinguished from a leaflet by the presence in its axil of a bud, branch, thorn, or flower; sometimes with lateral, basal appendages (stipules); either simple (toothed, lobed, or dissected but not divided into leaflets) or compound (divided into leaflets).
petioleorLeaf stalk, connecting leaf blade to stem; sometimes more or less indistinct.
bladebase, in hardened case at petiole base, in axils ofExpanded portion of a leaf, petal, or other structure, generally flat but sometimes rolled, cylindric, wavy, or cupped.
linearor scale-like leaves, or in terminal cone-like structure], seeds and pollen never formed [LYCOPHYTES and FERNS] ..... Group 3Elongate, with nearly parallel sides; narrower than elliptic or oblong.
5' Herbs to trees reproducing by seeds
6' Ovules enclosed in ovaries that on available specimens have matured asdehiscentorOpening at maturity to release contents; usually pertaining to anthers or fruits.
indehiscentfruits; seeds enclosed within ripened pericarp of fruit [if dry remains of flowers are present it may be possible to determine the family of a fruiting specimen under 1' in this key, but not all fruiting specimens may be identifiable here]Not opening inherently to release contents; usually pertaining to fruits.
1' Specimens available for examination with flowers, often also producing seeds within fruits [ANGIOSPERMS]
7' Specimens with open flowers8. Specimens with unisexual flowers of only 1 kind [staminate or pistillate, but not both]; plants dioecious or monoecious9. Specimen with only staminate flowers
9' Specimen with only pistillate flowers
8' Specimens withbisexualflowers or with both staminate and pistillate flowers [on same or different individuals]; plants bisexual, dioecious, or monoecious (occasionally with mixture of bisexual and unisexual flowers)Both male and female reproductive parts occurring and functional in the same plant or structure (e.g., flower, spikelet, inflorescence).
12' Pistil 1 per flower [carpel 1 or carpels > 1 fused at least proximally]13. Perianth 0 or in a single whorl [appearing to be either sepals or petals but not both], sometimes reduced to scale-like or bristle-like structures14. Tree or shrub, conspicuously woody15. Inflorescence, at least the staminate, acatkinor catkin-likeSpike or spike-like (e.g., Alnus) inflorescence of unisexual flowers with inconspicuous perianths (generally wind-pollinated), usually pendent and often with conspicuous bracts.
spike; flowers unisexual ..... Group 111. In flowering plants excluding Asteraceae, Cyperaceae, Poaceae, and some other groups, an unbranched inflorescence in which the flowers are sessile and nearly always open from the bottom to the top of the inflorescence. 2. In Asteraceae, Cyperaceae, Poaceae, and some other groups, a spike-like inflorescence is one in which the inflorescence units (e.g., heads in Asteraceae; spikelets in Cyperaceae and Poaceae), instead of individual flowers, are sessile and attached directly to the main axis of the inflorescence, not to branches, and in which floral development may or may not proceed as in 1.
14' Herb or subshrub, woody proximally if at all
16' Leaf venation generallypinnateorFeather-like; pertaining to veins, lobes, leaflets, or other structures arranged in two dimensions (i.e., in one plane) along either side of an axis; a leaf is odd-pinnate if there is a terminal leaflet, even-pinnate if there is not, and either odd- or even-pinnate may be 1-pinnate (blade divided into primary leaflets), 2-pinnate (primary leaflets divided into secondary leaflets), 3-pinnate (secondary leaflets divided into tertiary leaflets), etc.
palmate(sometimes only midvein evident) or leaves reduced to bladeless scalesMore than two structures or parts (e.g., veins, lobes, or leaflets) radiating from a common point in two dimensions (i.e., in one plane).
13' Perianth in 2 or more whorls (generally both sepals and petals) or perianth parts spiraled 2 or more times around floral axis
18' Perianth parts generally 4 or 5 per whorl (rarely some other number or whorls differing in number of parts) or in a spiral with the number of parts indefinite19. Petals fused into a ring or a tube, the corolla generally falling as a unit [corolla of free petals fused to ahypanthiumshould be keyed under 19']Structure generally in the shape of a tube, cup, or bowl, derived from the fused lower portions of the perianth and stamens, from which these parts seem to arise, and to which the ovary wall is fused in an inferior ovary (to which the ovary wall is partially fused in a half-inferior ovary; from which the ovary is free in a superior ovary).
20' Ovary superior
19' Petals free, at least at base, attached and generally falling singly (sometimes individually joined to ahypanthium; in a few families ± joined and falling in groups, but not forming a ring or a tube, or petal 1)
23' Ovary superior
24' Stamens <= 2 × as many as petals
Short underground stem and the fleshy leaves or leaf bases attached to and surrounding it (e.g., an onion).
Divisible into mirror-image halves in only one way.
Divisible into mirror-image halves in three or more ways.
Composed of a single part; undivided; unbranched.