WEEDS OF ARABLE LAND 109 



and wherever the weeds appear they should be spudded 

 out. Thorough cultivation of root crops will reduce 

 them. 



SCROPHULARIACE^ 



Yellow Toadflax (Linaria vulgaris L.) is seldom very 

 harmful, but occurs occasionally in arable land on 

 damp loams, and if inclined to grow strongly may be 

 some trouble, as it not only produces seeds, but is a 

 perennial with a creeping rootstock. It is an erect 

 plant i to 2 feet high, with narrow leaves i to 3 inches 

 long, and rather large tubular, spurred, yellow flowers 

 like those of the Snapdragon, with the upper and lower 

 lips lobed. The flowers are in dense spike-like racemes, 

 and appear from July to October. Yellow Toadflax is 

 in many localities a common weed by roadsides, and 

 in hedges and waste places. It should be prevented 

 from seeding by cutting, hoeing, or hand pulling, and 

 the creeping rootstocks should be removed during 

 tillage operations. 



Corn Speedwell ( Veronica agrestis L.) is a low, spread- 

 ing annual, slightly hairy, with very small, stalked, and 

 somewhat heart-shaped serrated leaves ; its small, pale 

 blue flowers are borne singly in the axils of the leaves, 

 and open between April and September. 



Ivy-leaved Speedwell (Veronica hedercefolia L.) is of a 

 similar habit and general appearance to the last species, 

 but rather larger. The leaves are cordate, with five to 

 seven large toothed lobes ; the pale blue flowers ap- 

 pear between March and August. 



Veronica Buxbaumii Ten. is a common colonist in 

 cornfields. It has long hairy stems, stalked cordate- 

 ovate leaves, and large handsome blue axillary flowers. 



These weeds, associated with other species of Speed- 

 well, commonly occur in arable land, especially corn- 



