Page:Popular Science Monthly Volume 41.djvu/237

From Wikisource
Jump to navigation Jump to search
This page has been validated.
225
PESTIFEROUS PLANTS.

or else that those tribunals which do exist be created into an intelligible succession, with one of last resort at the top, whose decrees shall be final to protect, as well as to discipline, both the railway company and its customers.

 

PESTIFEROUS PLANTS.
By Prof. BYRON D. HALSTED,

BOTANIST OF NEW JERSEY AGRICULTURAL COLLEGE EXPERIMENT STATION.

SOME plants, naturally, are better fitted to subserve the wants of man than others, and for the growth of these he puts forth special effort; in short, the whole underlying foundation of modern agriculture rests upon methods of favoring these plants and thereby enlarging and multiplying those qualities in them that led to their being chosen by man as objects of cultural attention. All plants, therefore, that now legitimately occupy space in our fields, orchards, and gardens are living an unnatural life, because they are in part creatures of selection and care; and it therefore follows that, owing to this stimulus under which they have flourished for generations, when the fostering hand of man is withheld they either perish or gradually drift back to the wild state and slowly lose many of their most valuable qualities as cultivated plants and regain those that better fit them for the stern battle of life. During the time while cultivated plants have been brought to a high plane of usefulness there have been many other species with no merit in their products that have stood in the way of the development of these fostered plants. The weeds have grown strong because obliged to fight their way and take every possible advantage when opportunity offers. They quickly win in the race for supremacy in every field devoted to cultivated crops, when man's care is withheld, and multiply their kind to an extraordinary extent. More reasonable it would be to expect a man under the softening influences of civilized life to win in the rough race for existence when placed, unaided, among savage Indians, than to hope for the success of a parsnip or onion seedling when surrounded by a rank growth of weeds.

There is nothing in the structure of a plant that Cain-like curses it forever. No part of the leaf, stem, fruit, or flower gives conclusive evidence that it belongs to a weed, and therefore we are forced back to the definition that was accepted a long time ago, namely, "A weed is a plant out of place." Its relation to others makes a plant a weed. A rose bush of the rarest variety, and one highly prized in its proper place, is a weed when occupying the soil to the detriment of some other plant that has the