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Vascular Plants of California
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Hilaria jamesii

Higher Taxonomy
Family: Poaceae (Gramineae)View DescriptionDichotomous Key
Habit: Annual to woody perennial herb; roots generally fibrous. Stem: generally round, hollow; nodes swollen, solid. Leaf: alternate, 2-ranked, generally linear, parallel-veined; sheath generally open; ligule membranous or hairy, at blade base. Inflorescence: various (of generally many spikelets). Spikelet: glumes generally 2; florets (lemma, palea, flower) 1--many; lemma generally membranous, sometimes glume-like; palea generally +- transparent, +- enclosed by lemma. Flower: generally bisexual, minute; perianth vestigial; stamens generally 3; stigmas generally 2, generally plumose. Fruit: grain, sometimes achene- or utricle-like.
Genera In Family: 650--900 genera; +- 10550 species: worldwide; greatest economic importance of any family (wheat, rice, maize, millet, sorghum, sugar cane, forage crops, ornamental, weeds; thatching, weaving, building materials). Note: Generally wind-pollinated. Achnatherum, Ampelodesmos, Hesperostipa, Nassella, Piptatherum, Piptochaetium, Ptilagrostis moved to Stipa; Elytrigia, Leymus, Pascopyrum, Pseudoroegneria, Taeniatherum to Elymus; Hierochloe to Anthoxanthum; Lolium, Vulpia to Festuca; Lycurus to Muhlenbergia; Monanthochloe to Distichlis; Pleuraphis to Hilaria; Rhynchelytrum to Melinis. The following taxa (in genera not included here), recorded in California from historical collections or reported in literature, are extirpated, lacking vouchers, or not considered naturalized: Acrachne racemosa (Roth) Ohwi, Allolepis texana (Vasey) Soderstr. & H.F. Decker, Amphibromus nervosus (Hook. f.) Baill., Axonopus affinis Chase, Axonopus fissifolius (Raddi) Kuhlm., Coix lacryma-jobi L., Cutandia memphitica (Spreng.) K. Richt., Dinebra retroflexa (Vahl) Panz., Eremochloa ciliaris (L.) Merr., Eustachys distichophylla (Lag.) Nees, Gaudinia fragilis (L.) P. Beauv., Miscanthus sinensis Andersson, Neyraudia arundinacea (L.) Henrard, Phyllostachys aurea Rivière & C. Rivière, Phyllostachys bambusoides Siebold & Zuccarini, Rottboellia cochinchinensis (Lour.) Clayton, Schedonnardus paniculatus (Nutt.) Branner & Coville, Schizachyrium cirratum (Hack.) Wooton & Standl., Schizachyrium scoparium (Michx.) Nash, Themeda quadrivalvis (L.) Kuntze, Thysanolaena latifolia (Hornem.) Honda, Tribolium obliterum (Hemsl.) Renvoize, Zea mays L., Zizania palustris L. var. interior (Fassett) Dore, Zoysia japonica Steud. Paspalum pubiflorum E. Fourn., Paspalum quadrifarium Lam., are now reported for southern California (J Bot Res Inst Texas 4:761--770). See Glossary p. 30 for illustrations of general family characteristics.
eFlora Treatment Author: James P. Smith, Jr., except as noted
Scientific Editor: James P. Smith, Jr., J. Travis Columbus, Dieter H. Wilken.
Genus: HilariaView DescriptionDichotomous Key

Habit: Perennial herb, cespitose, rhizomed. Stem: ascending to erect, solid; nodes generally hairy. Leaf: ligule membranous, ciliate-fringed; blade firm, flat to inrolled, sharply acute. Inflorescence: spike-like, generally cylindric; spikelets in clusters, 3 per node, +- equal; clusters wedge-shaped, overlapping, ascending to appressed, hairy-tufted at base, falling as 1 unit from zigzag axis; glumes of cluster together involucre-like. Central Spikelet: subsessile, appressed to or nearest inflorescence axis; glumes equal, < floret(s), oblanceolate, keeled, ciliate, tip deeply 2-lobed, lobes lanceolate, awns 3--9, 1 from +- mid-keel, others terminal; florets generally 1--2, lower floret bisexual, upper floret (if present) bisexual or staminate; lemma lanceolate, 3-veined, generally ciliate, tip generally 2-lobed, generally 1-awned +- from sinus; palea +- = lemma.Lateral Spikelet: sessile; glumes < to +- = florets, ciliate, lower glume asymmetric with 1 awn from +- middle near margin, generally 2-lobed, lobes unequal; florets 1--4, generally staminate; lemma 3-veined, tip generally ciliate; palea +- = lemma.
Species In Genus: 10 species: western United States to Guatemala. Etymology: (Auguste de Saint-Hilaire, French biologist, 1779--1853)
eFlora Treatment Author: J. Travis Columbus
Unabridged Reference: Reeder & Reeder 1988 Madroño 35:6--9
Hilaria jamesii (Torr.) Benth.
Habit: Plant 1.5--4(6.5) dm, unbranched above base. Stem: +- 1 mm diam; node hairs +- straight. Leaf: generally basal; generally glabrous or scabrous except long-ciliate near ligule; ligule membrane 1--3 mm, generally with lateral teeth; blade < 13(21) cm, 2--3 mm wide, adaxial surface sometimes with short, +- straight, hairs. Inflorescence: 3--7 cm; spikelet clusters 6--9 mm. Central Spikelet: glume margin hairs < 0.5 mm; lower lemma awn < 2.5 mm.Lateral Spikelet: lower glume 1-awned; upper glume tip unlobed or 2-lobed, awn 0--0.4 mm, margin hairs < 0.5 mm; lemma tip unlobed or 2-lobed, awn 0--0.4 mm, margin hairs 0--0.2 mm.Chromosomes: 2n=36,38,72.
Ecology: Dry, sandy to rocky slopes, flats, scrub, woodland; Elevation: 1000--2700 m. Bioregional Distribution: SNE, DMoj (mostly DMtns); Distribution Outside California: to Wyoming, Texas. Flowering Time: Apr--Nov
Synonyms: Pleuraphis jamesii Torr.
Jepson eFlora Author: J. Travis Columbus
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

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Botanical illustration including Hilaria jamesii

botanical illustration including Hilaria jamesii


Citation for this treatment: J. Travis Columbus 2012, Hilaria jamesii, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on June 27, 2022.

Citation for the whole project: Jepson Flora Project (eds.) 2022, Jepson eFlora,, accessed on June 27, 2022.

Hilaria jamesii
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© 2011 Steve Matson
Hilaria jamesii
click for enlargement
© 2011 Steve Matson
Hilaria jamesii
click for enlargement
© 2013 Steve Matson
Hilaria jamesii
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© 2009 Steve Matson
Hilaria jamesii
click for enlargement
© 2011 Steve Matson
Hilaria jamesii
click for enlargement
© 2011 Steve Matson

More photos of Hilaria jamesii in CalPhotos

Geographic subdivisions for Hilaria jamesii:
SNE, DMoj (mostly DMtns)
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map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).


Data provided by the participants of the  Consortium of California Herbaria.
View all CCH records
All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.

CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).