Gutierrezia microcephala
Gutierrezia texana
small-head snakeweed, sticky snakeweed, threadleaf snakeweed
Texas broomweed, Texas snakeweed
glabrous or minutely hispidulous.
glabrous.
basal and proximal absent at flowering;
cauline blades 1-nerved, linear or filiform to narrowly oblanceolate or lanceolate, 0.5–2.2(–4) mm wide, little reduced distally.
proximal usually absent at flowering;
cauline blades 1- or 3-nerved, linear, 1.5–4 mm wide, reduced distally.
cylindric, 1–1.5 mm diam.
campanulate to obconic, 2–4.5 mm diam..
1(–2; each enclosed by conduplicate inner phyllary);
corollas yellow, (1.5–)2–3.5 mm.
5–23;
corollas yellow, 3–6 mm.
1, sometimes 2 (functionally staminate; corollas broadly obdeltate-funnelform, throats widely flaring, lobes 1/3 corolla lengths, recurved-coiling).
7–48 (bisexual and fertile or functionally staminate).
(2–6, sessile to subsessile, in compact glomerules) in flat-topped arrays.
in loose arrays.
1–1.8(–2.5) mm, faces densely strigoso-sericeous;
pappi (rays, readily falling) of 1 series of narrowly lanceolate-oblong scales.
1.3–1.8 mm, faces without oil cavities, loosely strigose (hairs appressed, apices acute, microscopically 2-pronged);
pappi of 1 series of spreading-erect, oblong to ovate or obovate scales 0.1–0.5 mm (bases sometimes connate, usually shorter in rays, sometimes 0 in var. texana).
apices flat.
apices flat.
= 8, 16, 24, 32.
Gutierrezia microcephala
Gutierrezia texana
Gutierrezia microcephala is recognized by its perennial habit and its small, tightly clustered heads, each with 4–8 phyllaries and 1(–2) ray and disc florets. Each ray floret is enclosed by a conduplicate inner phyllary. Forms of G. sarothrae with few florets in each head can be distinguished by their bisexual and fertile disc florets and tubular-funnelform disc corollas.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Varieties 2 (2 in the flora).
Although the two varieties of Gutierrezia texana are similar, the geographic demarcation between them appears to be sharp, and a detailed investigation of their biologic interaction would be interesting.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Involucres (2–)3.5–4.5 mm diam.; disc florets 10–48; cypselae moderately to densely strigoso-sericeous, hairs usually in dense lines and at least partially obscuring faces; pappi of distinct scales 0.2–0.5 mm, rarely more reduced | var. glutinosa |
1. Involucres 2–3 mm diam.; disc florets 7–13; cypselae sparsely and evenly strigose, hairs not obscuring cypsela faces; pappi of continuous or scaly crowns less than 0.1 mm | var. texana |
CA
SW CO Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
IL Wildflowers
LA Plants
MO Plants
