EXTIRPATION OF VEGETABLES. 
71 
archer. It is much in request among wood carvers and turn¬ 
ers, and the demand for it explains, in part, its increasing 
scarcity. It is also worth remarking that no insect depends 
upon it for food or shelter, or aids in its fructification, no bird 
feeds upon its berries—the latter a circumstance of some 
importance, because the tree hence wants one means of propa¬ 
gation or diffusion common to so many other plants. But it 
is alleged that the reproductive power of the yew is exhausted, 
and that it can no longer be readily propagated by the natural 
sowing of its seeds, or by artificial methods. If further inves¬ 
tigation and careful experiment should establish this fact, it 
will go far to show that a climatic change, of a character unfa¬ 
vorable to the growth of the yew, has really taken place in 
Germany, though not yet proved by instrumental observation, 
and the most probable cause of such change would be found 
in the diminution of the area covered by the forests. 
The industry of man is said to have been so successful in the 
local extirpation of noxious or useless vegetables in China, that, 
with the exception of a few water plants in the rice grounds, it 
is sometimes impossible to find a single weed in an extensive 
district; and the late eminent agriculturist, Mr. Coke, is report¬ 
ed to have offered in vain a considerable reward for the detection 
of a weed in a large wheatfield on his estate in England. In 
these cases, however, there is no reason to suppose that dili¬ 
gent husbandry has done more than to eradicate the pests of 
agriculture within a comparatively limited area, and the cockle 
and the darnel will probably remain to plague the slovenly 
cultivator as long as the cereal grains continue to bless him.* 
* Although it is not known that man has extirpated any vegetable, the 
mysterious diseases which have, for the last twenty years, so injuriously 
affected the potato, the vine, the orange, the olive, and silk husbandry— 
whether in this case the malady resides in the mulberry or in the insect- 
are ascribed by some to a climatic deterioration produced by excessive de¬ 
struction of the woods. As will be seen in the next chapter, a retardation 
in the period of spring has been observed in numerous localities in South¬ 
ern Europe, as well as in the United States. This change has been 
thought to favor the multiplication of the obscure parasites which cause 
the injury to the vegetables just mentioned. 
Babinet supposes the parasites which attack the grape and the potato 
