DESCRIPTIVE MANUAL, 



263 



flowers sessile or nearly so, white; calyx segme&ts longer than the 

 corolla tube ; corolla f uniiel-form ; nutlets smooth. 



Distribution. — Common weed in fields in the east ; may be looked 

 for in southeastern Iowa. One of the most common weeds in grain 

 fields in Europe. 



Extermination. — The planis are easily destroyed. The seeds 

 probably retain their vitality for some time as the coat is hard. 

 VERBENACEAE, VERBENA FAMILY. 



The common cultivated verbena and lemon verbena belong to 

 this family. 



Blue Vervain {Verbena hastata L.). 

 Description. — A tall perennial 4-6 ft. high; leaves lanceolate, 

 coming to a point, cut-serrate, lower leaves often lobed; flowers in 

 erect, linear, corymbed spikes, violet-blue or rarely pink ; trichomes 

 simple, long, acuminate. 



Fig. 152. 



Vervain (Verbena hastata). Common in low pastures and meadows. 



a Trichome. 

 (Photographed by Quade. a drawn by Charlotte M. King.) 



