88 



Fig. 35. 

 Annual Sow Thistle, Common Sow Thistle, or Milk Thistle, 



Sonchus oleraceus, (L). 

 and Sonchus A^per, (Vill.) 



An annual weed introduced from Europe. It grows 2-3 feet 

 high, has fibrous roots and leafy stem, and is not quite so large or 

 coarse as the Perennial Sow Thistle. The leaves are much lobed, and 

 have short, soft spines. Each head is many-flowered ; but the flowers 

 are small, about h in. across, and of a pale yellow color. The seeds 

 are brown, thin, and about 1-8 in. long, with longitudinal markings, 

 and attached to the top is a large tuft of fine hairs united at the base. 



Time of flowering, June- August. 



Time of seeding, July- August. 



Dispersal- — chiefly by the wind. 



Eradication. Cultivate stubble-ground and sod early after har- 

 vest and throughout the fall as for Canada Thistle (See Fig. 30.) 

 Follow with hoed crop, preferably corn or roots, and cultivate 

 thoroughly throughout the growing season. Use the cultivator, 

 instead of the plow, after roots or corn ; sow a crop of grain and seed 

 with clover ; if practicable, pull the weeds by hand out of the grain 

 crop ; take one or two crops of hay or pasture, and again break up 

 the sod, plowing, harrowing and cultivating as for Thistle (Fig. 30). 



