62 



THE INDIANA WEED BOOK. 



stinging sensation. This nettle sting is one of the highest devices 

 by which plants guard themselves against the attack of animals. 

 Weeds, or shrubs with juicy tender leaves, are very apt to be 

 eaten by rabbits, cows, sheep, etc. Many of the wild plants have 

 therefore developed some means of protection, such as the spines 

 or prickles of the blackberry, thistle, rose and hawthorne ; the bitter 

 taste or bad smell of hound's tongue, dog- fennel and catnip; the 

 many hairs of the mullen, and the acrid or poisonous juice of the 

 buttercups, poison ivy, spurges and smartweeds. The nettle, how- 

 ever, is not only defensive but even aggressive in its protection, so 

 that when any herb-loving animal thrusts his tender nose against 

 it the sharp points pierce his skin, the liquid is injected into his 

 veins and he receives a lesson which prevents him from ever at- 

 tempting to devour another plant of its kind. Only three of our 

 nettles possess these stinging hairs. 



14. Trtica gracilis Ait. 



Slender Nettle. Tall Nettle. (P. N. 3.) 



Stein slender, erect, simple or few 

 branched, 2-6 feet high ; leaves oppo- 

 site, slender-stalked, ovate-lanceolate, 

 acuminate, sharply notched. Flowers 

 small, greenish, borne on slender pan- 

 i'cled spikes from the axils of the 

 leaves ; sepals and stamens 4, the flow- 

 ers dioecious, i. e., male and female 

 flowers on separate plants. Achenes 

 very small, oval, 1/20 inch long. 

 (Fig. 29.) 



Frequent in fence-rows and 

 along borders of cultivated fields, 

 especially in moist soil. June-Oct. 

 Stinging hairs few and the plant 

 spreading both by running root- 

 stocks and seeds. Remedies: mowing in June and again in August ; 

 burning mature plants in autumn ; grubbing or cultivation. 



Fig. 29. Showing a flower and fruit. (After 

 Britton and Brown.) 



15. Ubticastbum divaricatum L. Wood Nettle. Star Nettle. (P. N. 3.) 

 Stem rather stout, erect, 2-3 feet high; leaves alternate, thin, ovate, 

 long-stalked, sharply notched, pointed. Flower clusters large, loose; se- 

 pals and stamens of male flowers 5, sepals of female flowers 4, unequal. 

 A chen e ovale, flat, oblique, twice as long as the calyx. 



Common in dense woods in rich soil and in moist shady places. 

 July-Sept. Thickly clothed with stinging hairs. Remedies, same 

 as for preceding species. 



