HAIRY BEARDTONGUE





(Pentstemon hirsutus; P. pubescens of Gray) Figwort family



Flowers - Dull violet or lilac and white, about 1 in. long, borne

in a loose spike. Calyx 5-parted, the sharply pointed sepals

overlapping; corolla, a gradually inflated tube widening where

the mouth divides into a 2-lobed upper lip and a 3-lobed lower

lip; the throat nearly closed by hairy palate at base of lower

lip; sterile fifth stamen densely bearded for half its length; 4

anther-bearing stamens, the anthers divergent. Stem: 1 to 3 ft.

high, erect, downy above. Leaves: Oblong to lance shape, upper

ones seated on stem; lower ones narrowed into petioles.

Preferred Habitat - Dry or rocky fields, thickets, and open

woods.

Flowering Season - May-July.

Distribution - Ontario to Florida, Manitoba to Texas.



It is the densely bearded, yellow, fifth stamen (pente =five,

stemon = a stamen) which gives this flower its scientific name

and its chief interest to the structural botanist. From the fact

that a blossom has a lip in the center of the lower half of its

corolla, that an insect must use as its landing place, comes the

necessity for the pistil to occupy a central position. Naturally,

a fifth stamen would be only in its way, an encumbrance to be

banished in time. In the figwort, for example, we have seen the

fifth stamen reduced, from long sterility, to a mere scale on the

roof of the corolla tube in other lipped flowers, the useless

organ has disappeared; but in the beard-tongue, it goes through a

series of curious curves from the upper to the under side of the

flower to get out of the way of the pistil. Yet it serves an

admirable purpose in helping close the mouth of the flower, which

the hairy lip alone could not adequately guard against pilferers.

A long-tongued bee, thrusting in his head up to his eyes only,

receives the pollen in his face. The blossom is male (staminate)

in its first stage and female (pistillate) in its second.



While this is the beard-tongue commonly found in the Eastern

United States, particularly southward, and one of the most

beautiful of its clan, the western species have been selected by

the gardeners for hybridizing into those more showy, but often

less charming, flowers now quite extensively cultivated. Several

varieties of these, having escaped from gardens in the East, are

locally common wild.



The LARGE-FLOWERED BEARD-TONGUE (P. grandiflorus), one of the

finest prairie species, whose lavender-blue, bell-shaped corolla

is abruptly dilated above the calyx, measures nearly two inches

long. Its sterile filament, curved over at the summit, is bearded

there only.



Handsomest of all is the COBEA BEARD-TONGUE, a native of the

Southwest, with a broadly rounded, bell-shaped corolla, hairy

without, like the leaves, but smooth within. The pale purple

blossom, delicately suffused with yellow, and pencilled with red

lines - pathfinders for the bees - has the base of its tube

creamy white. Few flowers hang from each stout clammy spike.



The more densely crowded spikes of the large SMOOTH BEARD-TONGUE

(P. glaber), a smaller blue or purple flowered, narrower-leaved

species, that shows an unusual preference for moist soil

throughout its range, is, like the other beard-tongues mentioned,

better known to the British gardener, perhaps, than to Americans,

who have yet to learn the value of many of their wild flowers

under cultivation.



The tall FOXGLOVE BEARD-TONGUE (P. digitalis), with large, showy

white blossoms tinged with purple, the one most commonly grown in

gardens here, escapes on the slightest encouragement to run wild

again from Maine to Virginia, west to Illinois and Arkansas.

Small bees crawl into the broad tube, and butterflies drain the

nectar evidently secreted for long-tongued bees, but without

certainly transferring pollen. To insure cross-fertilization, the

flower first develops its anthers, whose saw-edges grating

against the visitors thorax, aid in sifting out the dry pollen;

and later the style, which when immature clung to the top of the

corolla, lowers its receptive stigma to oppose the bee's

entrance. Professor Robertson has frequently detected the common

wasp nipping holes with her sharp jaws in the base of the tube.

With remarkable intelligence she invariably chose to insert her

tongue at the precise spots where the nectar is stored on either

side of the sterile filament.





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