A SEED KEY TO COMMON WEEDS 335 



A SEED KEY TO SOME COMMON WEEDS AND PLANTS. 



E. L. PALMER. 

 INTRODUCTION. 



The aim of this thesis is three-fold. Primarily, it is written 

 to furnish a method of determining accurately the names of 

 various seeds and seedlike fruits with the express purpose of 

 detecting adulterants in commercial seeds. The key should 

 also aid in determining plants in the fruiting condition when 

 the flower parts are too far advanced for identification by the 

 ordinary method. Further, it should serve as a check to de- 

 terminations from a study of the flowers. 



The terms "weeds" and "seeds" may be variously inter- 

 preted. A weed has been defined as "a plant out of place" or 

 better still as a "useless or troublesome plant." Using the 

 latter interpretation, the author chose those plants which were 

 listed as troublesome weeds in the publications of various 

 agricultural experiment stations. A few other wild plants 

 were added and as special attention was paid to the adulter- 

 ants of the seeds of Red Clover, White Clover, Alsike Clover, 

 Alfalfa, Timothy, and Red Top, these seeds were inserted in 

 the key. The term ' ' seeds ' ' was interpreted in the broad sense 

 and includes not only true seeds but seedlike fruits such as are 

 found on Taraxacum officinale Weber (Dandelion), Arctium 

 minus (Burdock) ; etc. The botanical nomenclature used is 

 the same as that found in the seventh edition of "Gray's New 

 Manual of Botany" 1908. 



LITERATURE. 



Quite a few publications have been made in connection with 

 seed study. The work of Harz seems to be the most thorough 

 of these. It deals principally with the anatomy, histology and 

 chemical properties of various seeds. The bulletin of W. J. 

 Beal entitled "The Seeds of Michigan Weeds," 1910, gives 

 accurate descriptions of the more common weeds of Michigan. 

 Excellent illustrations by Mr. F. H. Hillman serve as a check 



