DESCRIPTIVE MANUAL 



107 



Fig. 60-A. Distribution of Maple-leaved Goosetoot. 



Lamb's Quarters, Pigweed. {Chenopodium album L.). 



Description. — ^An erect annual from 1-4 ft. high; young plants 

 generally mealy, older plants smooth ; leaves rhombic-ovate to lance- 

 olate or the upper sometimes linear, acute, lower commonly toothed ; 

 flowers produced in clustered, dense-spiked panicles ; calyx 5-parted, 

 nearly covering the seed ; seeds surrounded by a loose perioarp form- 

 ing an utricle. 



Distribution. — Native to Europe; widely naturalized in eastern 

 North America and the Rocky mountains ; occurs in Utah and on 

 the Pacific coast ; found everywhere in Iowa in cultivated fields and 

 in gardens as well as along highways. 



Extermination. — Plants of this species produce an enormous 

 number of seeds. The young plants are easily destroyed by cutting 

 off below the ground. Covering the young plants is not effective 

 unless the entire plant is covered. Older plants may be destroyed 

 by pulling them up. The weed on account of the shade it produces 

 destroys other vegetation underneath it. 



Chemical Composition. — According to a report of the Bussey In- 

 stitution, the chemical composition is as follows:* 



*Bull. Bussey Inst, 1877: Jenkins and Winton ; Office Exp. Sta., Bull. 11. 



