Al Schneider's Rocky Mountains Plant Descriptions

Mat Penstemon
Penstemon caespitosus
Plantain family (Plantaginaceae)

Mat Penstemon (Penstemon caespitosus) is, in the words of "Intermountain Flora", "a complex species with several races." Plants are mat forming ("") and widely spreading from one to several feet in diameter. Flowers are numerous, barely off the ground, and in delicate shades of lavender and blue. Stems are often recumbent, root at the , turn up at the end and have very narrow, slightly hairy leaves. Mat Penstemon could be confused with Linearleaf Penstemon(Penstemon linarioides) which has paler blue flowers, grows a bit taller and not as wide, and is found at lower elevations in the southwest part of Colorado. Mat Penstemon was first collected by Thomas Nuttall (in Wyoming in the 1830s) and Nuttall named it in 1862.


©2008 Al Schneider

Description

Plants , , to 5" tall, to slightly shrubby. Herbage hairy. Flowering stems can be to 9" long, with tips, or erect. Proliferating from previous years' stems, these eventually rooting, semi-woody. Leaves small to 3/5" long and to 1/5" wide, to or , narrowed to a short , . leafy, the flowers borne among the leaves or overtopping the leafy mat. 1/5 to almost 1" long, externally, bulged above, flattened and 2-ridged below, the projecting-spreading, the lower slightly longer than the upper, blue to blue violet. barely inserted, sacs blue. a .

Field Marks

Matted spreading plant of short, narrow leaves and numerous showy blue to purple flowers.

© Al Schneider

node -- The point at which there is attached growth, as in the place where each leaf is attached.

stamen -- the pollen-producing reproductive organ of a flower; The stamen consists of an anther supported by a filament.

An entire leaf has smooth edges. Not toothed or lobed.

A perennial plant lives and blooms for many years.

An inflorescence is a group or cluster of flowers arranged on a stem.

A herb is a plant whose stems die back to the ground in the winter.

corolla -- The name for all the petals of a flower taken together.

caespitose -- Grass (or plants) growing in small dense clumps or tufts.

spatulate -- spoon-shaped.

ascending -- growing obliquely upward and usually curved.

Glands are plant structures that secrete liquids, salts or other substances. Glands often appear as hairs with a drop of liquid at the end.

capsule -- a type of simple, dry fruit produced by many species of flowering plants. In most cases the capsule splits apart to release seeds.

fruit -- any seed-bearing structure in flowering plants. It is formed from the ovary after flowering.

The anther is a pad at the end of the stamen that holds the pollen.

obovate -- Teardrop-shaped, stem attaches to tapering point.

lobe -- A rounded parts of a leaf (or other organ).

petiole -- the stalk of a leaf.

prostrate -- Laying flat on the ground.

linear -- Long and very narrow like a blade of grass.