06 
ACCIDENTAL INTRODUCTION OF PLANTS. 
cannot say positively that any plant is uncultivable anywhere 
until it has been tried ; ” and this seems to be even more true 
of wild than of domesticated vegetation. 
The seven hundred new species which have found their 
way to St. Helena within three centuries and a half, were cer¬ 
tainly not all, or even in the largest proportion, designedly 
planted there by human art, and if we were well acquainted 
with vegetable emigration, we should probably be able to 
show that man has intentionally transferred fewer plants than 
he has accidentally introduced into countries foreign to them. 
After the wheat, follow the tares that infest it. The weeds 
that grow among the cereal grains, the pests of the kitchen 
garden, are the same in America as in Europe.* The over¬ 
turning of a wagon, or any of the thousand accidents which 
befall the emigrant in his journey across the Western plains, 
may scatter upon the ground the seeds he designed for his 
garden, and the herbs which fill so important a place in the 
rustic materia medica of the Eastern States, spring up along 
the prairie paths but just opened by the caravan of the settler.f 
power, and they soon perish when the nursing hand of man is withdrawn 
from them. In range of climate, wild plants are much more limited than 
domestic, but much less so with regard to the state of the soil in which 
they germinate and grow. 
Dr. Dwight remarks that the seeds of American forest trees will not 
vegetate when dropped on grassland. This is one of the very few errors 
of personal observation to be found in that author’s writings. There are 
seasons, indeed, when few tree seeds germinate in the meadows and the 
pastures, and years favorable to one species are not always propitious to 
another; but there is no American forest tree known to me which does 
not readily propagate itself by seed in the thickest greensward, if its germs 
are not disturbed by man or animals. 
* Some years ago I made a collection of weeds in the wheatfields of 
Upper Egypt, and another in the gardens on the Bosphorus. Nearly all 
the plants were identical with those which grow under the same conditions 
in New England. I do not remember to have seen in America the scarlet 
wild poppy 60 common in European grainfields. I have heard, however, 
that it has lately crossed the Atlantic, and I am not sorry for it. With 
our abundant harvests of wheat, we can well afford to pay now and then 
a loaf of bread for the cheerful radiance of this brilliant dower. 
t Josselyn, who wrote about fifty years after the foundation of the first 
