Burke: Psilocarphus brevissimus vs. Psilocarphus tenellus

	Psilocarphus brevissimus	Psilocarphus tenellus
	dwarf woolly-marbles	slender woollyheads
Habit	Small, woolly, monoecious annuals, usually prostrate and branching, the stems up to 10 cm. long.	Small annuals, the plants greenish to grayish, silky to spider-webby, the stems 2-10, prostrate to ascending.
Leaves	Leaves opposite, mostly lance-oblong to lance-linear, 5-25 mm. long and 2-5 mm. wide, usually well-surpassing the heads.	Leaves subtending the heads, spreading, not appressed to the heads, spatulate to obovate, 6-15 mm. long, the length 2 to 5 times the width and 1.5 to 2.5 times the head height.
Flowers	: Pistillate flowers 8-80 in each head, the corolla filiform-tubular, each enclosed by a saccate, woolly bract about 3 mm. long attached to the receptacle; receptacle lobed, each lobe bearing a cluster of as few staminate flowers; involucre none, but the heads subtended by several foliage leaves; pappus none; style off-set.	Heads discoid, spheroid, 3-5.5 mm. in diameter; involucre none; receptacle not lobed; pistillate flowers with a filiform-tubular corolla 1.5-2.7 mm. long, each enclosed by a saccate, woolly bract; staminate corollas usually 5-lobed, 0.8-1.5 mm. long; pappus none.
Fruits	Achenes obliquely lanceolate, flattened, 1.0-1.9 mm. long.	Achenes narrowly obovoid, slightly compressed, 0.7-1.2 mm. long.

	Psilocarphus brevissimus	Psilocarphus tenellus
Flowering time	May-July	March-August
Habitat	Dried beds of vernal pools.	Dry or seasonally moist barren or wooded slopes or flats, often on disturbed sites.
Distribution	Occurring east of the Cascades crest in Washington; British Columbia to California, east to the northern Great Plains and Rocky Mountains. [WildflowerSearch map] [BONAP county map]	Occurring on both sides of the Cascades crest in Washington; southwestern British Columbia to California, east to Idaho. [WildflowerSearch map] [BONAP county map]
Origin	Native	Native
Conservation status	Not of concern	Review Group 1 in Washington (WANHP)
Sibling taxa	P. elatior, P. oregonus, P. tenellus	P. brevissimus, P. elatior, P. oregonus
Subordinate taxa	P. brevissimus var. brevissimus
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Psilocarphus brevissimus

Psilocarphus tenellus

dwarf woolly-marbles

slender woollyheads

Habit

Small, woolly, monoecious annuals, usually prostrate and branching, the stems up to 10 cm. long.

Small annuals, the plants greenish to grayish, silky to spider-webby, the stems 2-10, prostrate to ascending.

Leaves

Leaves opposite, mostly lance-oblong to lance-linear, 5-25 mm. long and 2-5 mm. wide, usually well-surpassing the heads.

Leaves subtending the heads, spreading, not appressed to the heads, spatulate to obovate, 6-15 mm. long, the length 2 to 5 times the width and 1.5 to 2.5 times the head height.

Flowers

: Pistillate flowers 8-80 in each head, the corolla filiform-tubular, each enclosed by a saccate, woolly bract about 3 mm. long attached to the receptacle;

receptacle lobed, each lobe bearing a cluster of as few staminate flowers;

involucre none, but the heads subtended by several foliage leaves;

pappus none;

style off-set.

Heads discoid, spheroid, 3-5.5 mm. in diameter;

involucre none;

receptacle not lobed; pistillate flowers with a filiform-tubular corolla 1.5-2.7 mm. long, each enclosed by a saccate, woolly bract; staminate corollas usually 5-lobed, 0.8-1.5 mm. long;

pappus none.

Fruits

Achenes obliquely lanceolate, flattened, 1.0-1.9 mm. long.

Achenes narrowly obovoid, slightly compressed, 0.7-1.2 mm. long.