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(which droop) stand out stiffly, and more or less upright from 

 the bark on which they grow. Stalks are usually 4 or 5 cm. high, 

 but may reach two or three times that size. 



The general color is greenish gray (ashy gray in dry weather), 

 often blackening along the stalks or occasionally stained reddish 

 in places. The main stalk, frequently 2 mm. or more in thickness, 

 is rounded, sometimes cracked in rings, showing a white core 

 within, due probably to being pulled by climbing animals, or 

 by ice. Its surface is beset with tiny warts visible under the 

 hand lens, and with profuse branches, branchlets and fibrils, 

 most of which stand out nearly at right angles to the stalk from 

 which they spring. Various parts may or may not be dotted with 

 dusty white specks known as soredia. 



The fruit, a thin disk up to 1 cm. or more in diameter, 

 flesh-colored, buff, pale greenish or pinkish, its irregular rim 

 usually fringed with rather long fibrils, does indeed suggest a 

 flower. Usnea florida will be found without fruit more often 

 than with. 



When very small, compact, and intricately branched, it may 

 be called Usnea hirta (L.). These two are the only erect Usneas, 

 all other forms drooping downward. 



Usnea harhata (L). Bearded Lichen 



Hanging downward like a beard, slender, flexible, blowing 

 in the wind, of any length up to a meter or two, typical Usnea 

 harhata is easily distinguished from typical stiff, erect U. florida. 

 It is less densely branched as a rule, and the smaller fruits, 

 rarely seen, occur along the branches rather than at their tips, 

 otherwise much like U. florida. If you call all drooping forms 

 Usnea harhata, you will not be far wrong, for the other species 

 are often considered mere varieties of it. 



Usnea plicata (L.) is coarser than U. harhata, with larger 

 fruits, and in fact looks more like U. florida except that it is 

 flexible, hangs downward, and fruits along the branches. U. 

 longissima Ach. has scales instead of warts, and fruits at the 

 tips, though fruits, as in U. harhata, are rare. U. angulata, also 

 without warts, has somewhat. angled stems, and though droop- 

 ing like U. harhata, is rigid like U. florida. U. cavernosa Tuck, 

 differs from U. harhata in having the stem conspicuously pitted 

 near the base. It is interesting to observe these minor variations, 



