National Geographic : 1921 Aug
PROTECTING THE UNITED STATES FROM PLANT PESTS BY CHARLES LESTER MARLATT CHAIRMAN, FEDERAL HORTICULTURAL BOARD, U. S. DEPARTMENT OF AGRICULTURE With Photographsfrom the U. S. Department of Agriculture Some ten years ago the NATIONAL GEOGRAPHIC MAGAZINE, by the publication of an article on "pests and parasites," aided materially in securing the passage of a national law to prevent importation of insect-infested and diseased plants.* The accompanying article and the illustrations indicate the character of plant pests which are being intercepted by this law. PRIOR to 1912 there was no au thority in law to protect the United States from the entry of new plant enemies or to control and prevent the dis tribution within the United States of any such enemies which may have gained limited foothold. Not only could plants be imported by nursery and florist establishments without regard to their freedom from pests, but, in the absence of any protective legisla tion, America became a dumping ground for the plant refuse of other countries. It was common practice of big nursery establishments abroad to consign, without order, tons of their culls to department stores, to florists, and even to auctioneers of this country, to be sold or given away by such stores or auctioned for what they would bring. This freedom of entry, in the absence of authority for inspection or other in surance of freedom from insect pests and diseases, has resulted during the last cen tury in the establishment in the United States of an enormous number of foreign plant pests which are, and will remain, a tremendous burden on the garden, field, and forest productions of this country. THE FOOD BILL OF PLANT PESTS OF FOREIGN ORIGIN Several years ago the Department of Agriculture issued a careful analysis of the losses caused to the principal crops of the United States by insect pests, * Pests and Parasites; Why We Need a National Law to Prevent Importation of In sect-Infested and Diseased Plants. By Charles Lester Marlatt. NATIONAL GEOGRAPHIC MAGA ZINE, April, 1911. showing that these losses amounted to upward of a billion dollars a year, a sum at that time more than sufficient to meet the entire cost of the administration of the Federal Government! That was under the old price of crops. Under recent prices these losses would approxi mate two billion dollars annually !f These estimates relate solely to losses due to the insect pests and take no ac count of the losses due to such plant dis eases as the grain rusts and smuts and the mildews, blights, and hundreds of other diseases affecting every important crop and also many forest trees and orna mentals. Such plant diseases probably occasion losses fully comparable to those due to insects. These losses are caused by a host of pests, insect and fungous, that affect fruits, farm crops, and forest trees, but more than 50 per cent of these losses are due to insect and diseases which have come to us from foreign lands. Among these are some of the worst enemies of our principal crops. Examples of such are the Hessian fly, the boll weevil of cotton, the alfalfa weevil, the Japanese beetle, the San Jose scale, and such plant diseases as the wheat smut, pine blister rust, citrus canker, potato wart, chestnut blight, and many others. Altogether, these unwelcome immi grants, insects and diseases, include up ward of 1oo important plant enemies and t The detailed discussion of these losses is published in the Year Book of the Department of Agriculture for 1904, and a later summary is given in the report of the Roosevelt Na tional Conservation Commission.