Isocoma menziesii

(Hooker & Arnott) G. L. Nesom

Phytologia 70: 93. 1991.

Common names: Pacific jimmyweed Menzies’ goldenbush
Basionym: Pyrrocoma menziesii Hooker & Arnott Bot. Beechey Voy., 351. 1838
Treatment appears in FNA Volume 20. Treatment on page 442. Mentioned on page 440.

Herbage glabrous or villlous, sometimes stipitate-glandular, not resinous. Leaf-blades obovate to spatulate or oblanceolate to nearly linear, 5–40 mm, margins entire or toothed to lobed. Involucres (6–) 7–9 × 6–8 mm. Phyllary apices green to yellowish, not aristate, sometimes with weakly developed, non or weakly spinulose projection, gland-dotted, without resin pockets or pockets small, weakly developed (var. decumbens and var. menziesii). Florets (15–) 18–25 (–28); corollas 5–7 mm. Cypsela ribs not forming apical horns.

Discussion

Varieties 5 (5 in the flora).

Selected References

None.

Key

1 Leaf blades mostly obovate, thick-fleshy, margins coarsely serrate; stems decumbent, prostrate, or pendent; herbage glabrous Isocoma menziesii var. sedoides
1 Leaf blades obovate to oblanceolate, usually not thick-fleshy, margins entire or toothed (if so then at least stems densely villous); stems erect to ascending or decumbent; herbage glabrous, villous, tomentose, or stipitate-glandular > 2
2 Herbage essentially glabrous, stipitate-glandular > 3
2 Herbage glabrous, villous, or tomentose, not prominently glandular or glands beneath other vestiture > 4
3 Stems prostrate to decumbent or ± erect; leaves 5–22 × 2–4 mm; heads in corymbiform to loose, paniculiform arrays; cypselae 2.3–3.6 mm; San Diego County southward Isocoma menziesii var. decumbens
3 Stems strictly erect; leaves 20–40 × 4–10 mm; heads in corymbiform arrays; cypselae (3.8–)4.5–5 mm; San Benito and Santa Clara counties Isocoma menziesii var. diabolica
4 Plants densely tomentose or villous > 5
4 Plants glabrous or glabrate > 6
5 Herbage finely and closely grayish-arachnoid-tomentose; leaf blades narrowly oblanceolate, 5–22 × 2–4 mm, margins entire or with 1–2 pairs of teeth distally Isocoma menziesii var. decumbens
5 Herbage hirtellous, villoso-pilose, or densely gray-tomentose (hairs flattened, vitreous, long); leaf blades linear to oblanceolate or spatulate-oblong, 10–40 × 2–6(–9) mm, at least proximal leaves with toothed margins Isocoma menziesii var. vernonioides
6 Leaf margins entire or with 1–2 pairs of teeth or shallow lobes distally Isocoma menziesii var. menziesii
6 At least proximal leaves toothed along most margins Isocoma menziesii var. vernonioides

"thick" is not a number.

... more about "Isocoma menziesii"
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Guy L. Nesom +
(Hooker & Arnott) G. L. Nesom +
decurrent +
Pyrrocoma menziesii +
0.5 cm5 mm <br />0.005 m <br /> (4 cm40 mm <br />0.04 m <br />) +
obovate +  and spatulate or oblanceolate +
linear;oblanceolate or obovate +
rugulose +  and muricate +
Pacific jimmyweed +  and Menzies’ goldenbush +
not 2-lipped +  and actinomorphic +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
subterete +, terete +  and obpyramidal +
fertile +  and bisexual +
fertile +  and bisexual +
Calif. +  and nw Mexico +
gland-dotted;gland-dotted +
sericeous +, tomentose +, glabrous +, villous +  and hispidulous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
indeterminate +
heterogamous +  and homogamous +
not resinous +
stipitate-glandular +, villlous +  and glabrous +
each +  and sessile +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
obconic;turbinate or campanulate +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
deltate +
dentate to pinnatifid +  and entire +
toothed +  and lobed +
2-carpellate +
persistent +
oblong +  and elliptic-lanceolate +
styliferous +, neuter +  and pistillate +
bearing subulate enations +, hairy +  and bristly +
concave;usually flat;conic +
exalbuminous +
eglandular +  and few-branched +
resinous +
gland-dotted +
stipitate-glandular +, tomentose +, villous +, hispidulous +  and glabrous +
appendaged +  and truncate +
papillate +  and smooth +
Haplopappus sect. Isocoma +
Isocoma menziesii +
species +
goblet--shaped +
ampliate +
dark orange-resinous +
120 cm1,200 mm <br />1.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
20 cm200 mm <br />0.2 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
120 cm1,200 mm <br />1.2 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +