Jepson Flora Project: Jepson Interchange    

link to manual TREATMENT FROM THE JEPSON MANUAL (1993) previous taxon | next taxon
Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California
For up-to-date information about California vascular plants, visit the Jepson eFlora.



David J. Keil, Family Editor and author, except as specified

Annual to tree
Leaves basal or cauline, alternate to whorled, simple to compound
Inflorescence: 1° inflorescence a head, each resembling a flower, 1–many, generally arrayed in cymes, generally subtended by ± calyx-like involucre; flowers 1–many per head
Flowers bisexual, unisexual, or sterile, ± small, of several types; calyx 0 or modified into pappus of bristles, scales, or awns, which is generally persistent in fruit; corolla radial or bilateral (rarely 0), lobes generally (0)4–5; stamens 4–5, anthers generally fused into cylinder around style, often appendaged at tips, bases, or both, filaments generally free, generally attached to corolla near throat; pistil 1, ovary inferior, 1-chambered, 1-seeded, style 1, branches 2, generally hair-tufted at tip, stigmas 2, generally on inside of style branches
Fruit: achene, cylindric to ovoid, generally deciduous with pappus attached
Genera in family: ± 1300 genera, 21,000 species (largest family of dicots): worldwide. Largest family in CA. Also see tribal key to CA genera: Strother 1997 Madroño 44(1):1–28. See glossary p. 25 for illustrations of general family characteristics.



Perennial, subshrubs, shrubs
Stems generally white, glabrous or hairy
Leaves simple, alternate, entire or toothed; midrib white
Inflorescence: heads radiate, solitary, peduncled; involucre bell-shaped or hemispheric; phyllaries graduated in several series; receptacle convex, naked
Ray flowers generally many; corollas white to blue or purple
Disk flowers many; corolla yellow; style tips linear, acute
Fruit linear to club-shaped, weakly compressed, covered with long, appressed hairs; pappus of many, unequal bristles
Species in genus: 8 spp: w North America:
Etymology: (Greek: woody root)
Reference: [Watson 1977 Brittonia 29:199–216]


X. orcuttii (Vasey & Rose) Greene


Shrub < 1.5 m
Stems glabrous (rarely puberulent below heads)
Leaves 2–6 cm, oblanceolate to oblong or lanceolate, glabrous or sparsely hairy on margins, obtuse or acute, ± spiny-dentate or entire, not much reduced upward
Inflorescence: heads sessile (or peduncle < or = 11 cm); phyllaries 5–12 mm, 1.5–3.5 mm wide, glabrous, innermost = or > immediately preceding series
Ray flowers 25–40; tube 4–6 mm; ligule 1.2–3.2 cm, light blue
Disk flowers 55–140; corolla 8–10.5 mm
Fruit 3–4 mm; pappus bristles < or = 12 mm
Chromosomes: 2n=12
Ecology: Arid canyons
Elevation: 20–300 m.
Bioregional distribution: s Sonoran Desert (Imperial, San Diego cos.)
Flowering time: Mar–Apr
Synonyms: Machaeranthera o. (Vasey & Rose) Cronquist & D.D. Keck
See the CNPS Inventory for information about endangerment and rarity.
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bioregional map for XYLORHIZA%20orcuttii being generated
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).

Retrieve Jepson Interchange Index to Plant Names entry for Xylorhiza orcuttii
Retrieve dichotomous key for Xylorhiza
Retrieve multiple-entry key (MEKA) for Xylorhiza
Overlay Consortium of California Herbaria specimen data by county on this map
Show other taxa with the same California distribution | Read about bioregions | Get lists of plants in a bioregion
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