Pseudognaphalium leucocephalum
Pseudognaphalium saxicola
white cudweed, white rabbit-tobacco
cliff cudweed
densely and persistently white-tomentose, usually with stipitate-glandular hairs protruding through tomentum.
(filiform) persistently tomentose (indument a loose, envelope-like, transparent haze of extremely thin hairs, doubling apparent stem width), not glandular.
blades (crowded, internodes mostly 1–3, sometimes to 10 mm) linear-lanceolate, 3–7 cm × 1–5(–6) mm, bases subclasping, not decurrent, margins strongly revolute, faces bicolor, abaxial densely white-tomentose, adaxial green, densely stipitate-glandular.
blades elliptic-oblanceolate to oblanceolate, 0.5–3 cm × 2–6 mm (largest at midstem), bases not clasping, not decurrent, margins flat, faces concolor, green, thinly arachnoid-tomentose to glabrate, not glandular (veiny reticulum evident).
broadly campanulate, 5–6 mm.
turbinate, 4–5 mm.
66–85.
25–28.
(6–14, California)29–44.
6–7.
in 5–7 series, bright white (opaque, dull), oblong to oblong-ovate, glabrous.
in 3(–4) series, whitish to slightly tawny (hyaline, shiny), narrowly triangular to narrowly oblong-triangular, glabrous.
in corymbiform arrays.
(2–4) in terminal, capitate clusters (usually immediately subtended by distalmost cauline leaf, clusters sometimes in subcorymbiform arrays).
ridged, smooth.
not ridged, smooth.
= 28.
Pseudognaphalium leucocephalum
Pseudognaphalium saxicola
Pseudognaphalium leucocephalum is similar to P. viscosum, which has shiny, hyaline, ovate-lanceolate phyllaries, 200–250 pistillate florets, (13–)16–29 bisexual florets, and papillate-roughened cypselae. Some plants of P. leucocephalum also appear to approach P. biolettii in general appearance, and it is possible that some of them may represent hybrids. Plants of P. biolettii differ from P. leucocephalum in their typically eglandular stems, broader, basally ampliate, clasping, more widely spaced, and less densely glandular leaves, and thinner, shiny phyllaries.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Pseudognaphalium saxicola probably is an evolutionary derivative of P. obtusifolium. Plants of P. saxicola are relatively small and have relatively few, relatively small heads and occur in a specialized habitat; they constitute the only narrowly endemic species of Pseudognaphalium in the United States. Depauperate individuals of P. obtusifolium from localities over its whole geographic range may sometimes be as short as 5–10 cm and similar in habit to P. saxicola; such plants differ from P. saxicola in their close and denser stem vestiture, bicolor and relatively narrow leaves, larger heads with greater numbers of pistillate florets, and broader phyllaries with rounded apices.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
