A SECOND OHIO WEED MANUAL. 371 



rightly been outlawed in most state weed laws. It is nearly always spread 

 by the seeds, which are carried in hay and in seeds of various sorts. Large 

 portions of Ohio are comparatively free from oxeye daisy, while it is found 

 to be a bad pest in many counties. Perennial by short, rather thick rootstocks, 

 it must be entirely uprooted before it will perish. 



Seeds gray to black as viewed, broader above, with many light colored ribs 

 lengthwise, 1-12 inch long, no pappus and with a sharp point. Frequent in 

 grass seeds, wherein it is an impurity forbidden by statute. Oxeye daisy, like 

 narrow plantain, requires careful cultivation to destroy it. Where but few 

 plants are found these may be removed by hand digging, but no badly infested 

 field should be continued in grass without first cultivating the weeds out of 

 existence. With this, as with several other weeds, the whole community is 

 concerned when one resident permits it to grow and fails to make sufficient 

 effort to destroy it. 



370 Costmary (P) * Chrysanthemun Balsamita L. This plant, locally 

 called lavender (erroneously), often with rayless yellow heads, is a frequent 

 weed about old gardens. The scented leaves are recalled by most persons. 

 Requires grubbing 



371 Feverfew (P) * Chrysanthemum Parthenium (L.) Pers, Is a third 

 weedy species of the genus. This has rather pretty heads of small size. 



372 Tansy (P) *Tanacetumvulgare L. Tansy is often planted and remains 

 unless carefully destroyed. It has yellow heads of flowers m dense, fiat-topped, 

 clusters, and much dissected leaves. It is a bitter, acrid and showy, ill-smelling 

 herb. Seeds angled and ribbed, 1-10 inch long with a large, flat top and a 

 short crown. Plants destro3^ed by cultivation or by grubbing. 



373 Wormwood (B) Artemisia biennis D. This weed grows from 2 to 3 

 feet high, and has divided, narrowly lobed leaves and inconspicuous heads. 

 The plant has a penetrating, though not entirely unpleasant odor and a bitter 

 taste. It grows with an erect habit and a leafy stem. It has been introduced 

 into a large number of southeastern counties as well as about cities. Seeds 

 small, slender, 1-20 inch long. Destroyed by pulling or grubbing. 



374 Mugwort (P) * Artemisia vulgaris L. Mugwort resembles the pre- 

 ceding but has smaller heads and perennial roots. It is the more objectionable. 



375 Fireweed (A) Erechthites hieracifolia Raf. This plant is a tall, rank- 

 smelling weed with grooved stem and thin, cut-toothed, tapering leaves. The 

 flowers are whitish, succeeded by an abundance of seeds having a large tuft of 

 hairs on each. This is the weed of new clearings and logheaps. It is attacked 

 by two leaf mildews, Erysiphe communis (Wallr. ) Schw. and Sphcr rot hec a Cas- 

 tagnei L£v. and also by Septoiia Erechthites Ell & Ev. Being an annual it is 

 easily destroyed by cutting, pulling or digging before the blossoms open. 



376 Common Groundsel (A) *Senecio vulgaris L. This is a.hollow- 

 stemmed plant, a foot or more high, with incised, oblong leaves and many 

 rayless heads. Now infrequent but destined to become an unsightly and 

 common pest in cultivated ground and waste places. 



377 Burdock (B) * Arctium Lappa L. With its very large, rounded leaves 

 and tall stems, having small heads of purplish flowers, the burdock is scarcely 

 unknown. The heads become armed with hooked tips, making them like the 

 burs of Xanthium in adhesiveness. They prove vile pests in the wool of sheep 

 and in the manes of horses. The plant has very large, deep roots. 



Seeds light brown, spotted with darker, wider above, 1-12 inch long, with 

 occasional lines lengthwise and a short, bristly pappus; occasionally found 

 in seeds. Burdocks may be removed with mattock if done before flowering 1 . 

 Certainly if conspicuousness of a plant leads to its recognition there is no reason 

 why burdock should be so often seen about fields and roadsides. 



