352 OHIO EXPERIMENT STATION: BULLETIN 175. 



48b. This pretty thing is as difficult as horse-nettle or Canada thistle to eradi- 

 cate; where fields become infested, fences should b£ removed and continuous 

 cultivation be practiced. There is no middle ground with weeds of this class, 

 they must be destroyed utterly or the}- take full possession of the fields. When 

 dooryards and lawns are infested the same cultivation may be used, since hand 

 digging will not destroy them. 



262 Heai=all, Self=heal (P) *Pni7iella vulgaris L. Is a common plant in 



low, grass land and by roadsides, growing about a foot high, with egg-shaped 



to oblong leaves and violet-blue flowers in a dense head. Seeds brown shaped like 



a grape seed, 1-16 inch long, half as wide, smooth, shining, with a few darker 



lines lengthwise of the seed; not rare in hay. To be killed by free use of hoe. 



263 Horehound (P) * Marmbium vulgare L. Commonly grows about a 

 foot in height, having round, egg-shaped, stalked, scallop-toothed leaves and 

 dense heads of small, white flowers about the base of the leaves. The heads 

 are prickly later from the teeth of the calyx. The whole plant is whitish-woolly 

 and bitter aromatic. Frequently found infields and waste places. 



Seeds straw color to brown, broader toward one end, somewhat triangular 

 with the characteristic shape of the mints, 1-12 of an inch long. While useful 

 in domestic medicine, perhaps, horehound should be killed out in fields and 

 waste places. 



264 Hedge=nettle (P) Stachys palustris L. Growing frequently in wet 

 ground along ditches and 1he borders of swamps, two to three feet in height, 

 with four-angled stems and numerous, scalloped, saw-toothed leaves. Flowers 

 are very small, clustered in the angles of the leaves. It is an unsightly weed, 

 killed out by cutting or cultivation after sufficient drainage to permit the growth 

 of grasses. 



265 Wild Sage (P) ^Salvia veibenacea L. Wild sage is locally naturalized 

 and may be recognized by its hairy stems and cut-tooothed leaves. It requires 

 close cutting to destroy' the plants. 



266 Motherwort (P)*Leonurus Cardiaca L. Motherwort is a common, tall 

 perennial weed with its four-sided stems, lower rounded and upper finger-lobed 

 leaves. The pale, bearded flowers are in clus- 

 ters at the base of the leaves. 



Seeds dark, sharply triangular with one 

 curved side, the flat top covered with hairs, 1-12 

 of an inch long, somewhat shining. Best killed 

 out by cultivation; may be destroyed by repeated 

 cutting with hoe or by the free use of salt. 



267 Dead=nettle (A) *Lamium amplexi- 

 caule L. Dead-nettle is a recently acquired 

 winter annual or biennial weed against which 

 a sharp warning is needed. It has low stems, 

 rounded, scalloped leaves clasping the stem and 

 bright red-purple flowers in whorls at the top, 

 see Fig. 49. It is becoming very frequent in 

 lawns and gardens, proving aggressive in both 

 situations. It should be watched for and eradi- 

 cated upon its appearance. Two other species FlG 49 Dead-nettle. 

 are of local occurrence. Also called henbit. 



Seeds gray, curved, triangular, 1-20 of an inch long, with whitish markings 

 over the surface. Promising to become as omnipresent as those of peppergrass. 

 Enough has been said of this to show the urgent necessity of prevention and 

 destruction. The plant begins to blossom by March and forms its seeds very- 

 early, thus making promptness necessary. It should be treated as recommended 

 for peppergrass and shepherd's purse by growth of a winter crop of some sort 

 and by thorough cultivation. 



