28 



BULLETIN OF 

 MASSACHUSETTS BOARD OF AGRICULTURE. 



MASSACHUSETTS WEEDS. 



By Or. E. Stone, Ph.D., ProfeHnor of Botany at Massachusetts Agricultural College. 



Emerson defines a weed as a plant whose virtues have not been 

 discovered. The general conception of weeds is that they are 

 useless plants, and this conception would include all of our road-side 

 growths, such as golden-rods, etc. To the farmer, however, a 

 weed, is not only a useless but a troublesome plant. Apropos of 

 Emerson's conception of a weed, it may be stated that there are 

 apparently useless plants whose virtues have been discovered, or, 

 in other words some use has been made of them. ■ The barn-yard 

 grass, which is a weed throughout Europe and America, has been 

 cultivated in Japan and is now a very important forage plant. 



We can divide all of our plants into three groups, — the indige- 

 nous, or native species, the naturalized, or those which have become 

 established ; and the adventive, or those which have made their 

 appearance once or twice but which have not become established. 

 The latter two groups, the naturalized and the adventive, include, 

 of course, the introduced species which grow spontaneously. It 

 must be understood, however, that they do not include all cultiva- 

 ted species. The naturalized species make tliemselves at home in 

 our soil, and they grow year after year with more or less regu- 

 larity in tlieir appearance. 



The adventive plants are only recent arrivals, and may be con- 

 sidered as candidates for admission. Some of them make their 

 appearance sparingly year after year, without making much head- 

 way, while otliers simply live one year and perhaps are not seen 

 again, or only occasionally from time to time. The conditions 

 which largely control the appearance of the new plants are depend- 



