18 MASSACHUSETTS HORTICULTURAL SOCIETY. 



The question is often asked, why it is that so many of our 

 noxious weeds are of European origin while our own native spe- 

 cies are comparatively innocent of offense. This question is of 

 vei-y great interest. Originally the forested areas of northern 

 and central Europe were not unlike our own wooded countrj', 

 and the herbaceous plants of the leaf mold were similar to and 

 often identical with our own woodland species. For centuries, 

 however, the catting and recutting of the forests and the tre- 

 mendous growth of towns and of closely cultivated land has left 

 most of these species practical outcasts, hiding here and there 

 in cold mountain regions and swamps. This virtual deforesting 

 of large tracts of Europe and the consequent destruction of the 

 fastidious woodland species has very naturally increased the 

 opportunity for development of genera and species which thrive 

 best in the open ; and so we now find spread widely over civi- 

 lized Europe the numberless species of such characteristic genera 

 as the hawkweeds {Hieracium)^ the thistles (Cirsium, Carduus, 

 etc.), the poppies (Papaver) , mustards (^Brassica, Sisy^nbrhim^ 

 etc.), vetches (Vicia, etc.), bedstraw^s (Galiwyi), and star thistles 

 {Centaurea). Life for hundreds of generations along the roads 

 and fence rows, on the outskirts of civilization, has developed in 

 these plants a vigor and hardiness and an indifference to sur- 

 roundings striking^ in contrast with the sensitive constitutions of 

 the woodland species they have now so thoroughly suj^planted. 

 These hardy races, then, developed as the result of long compe- 

 tition in fence corners and hedgerows of Europe are able to cope 

 M-ith conditions which are practically impossible to the less sturdy 

 types developed along our New England rivers. This point is 

 well illustrated by the common plantain of our roadsides. In all 

 its characteristics this plant is exactly the Plantago major of 

 Europe, and throughout America it is this t^^jical thick-leaved 

 European plant which abounds by roadsides. A thinner-leaved 

 Aariety of Plantago tnajor is common in the alluvium and along 

 the river beaches of northern Xcav England and Canada, but, so 

 far as our observations show, this thin-leaved native plant never 

 deserts the river l)ank, Avhile its less fastidious European repre- 

 sentative is quite at home in the precarious surroundings of busy 

 roadsides and beaten paths. Similarly the yarrow, self-heal, 



