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Experiment Station Work, LIII

其他書名	Inoculation and Lime for Alfalfa, Preventing Losses at Lambing Time, Citrus Culture in Southern Texas, Winter Lambs for the Pacific Coast Market, Pruning Rotundifolia Grapes, Feeding Work Horses, Native Hays of Arid Region, Colony Houses for Poultry, Bermuda Grass, Food of the Crow Blackbird, Short V. Long Feeding of Beef Cattle, Flour for Baking Powder Biscuits, Contagious Abortion of Cattle
出版	U.S. Department of Agriculture, 1910
URL	http://books.google.com.hk/books?id=VFH9gF45k1kC&hl=&source=gbs_api
EBook	FULL_PUBLIC_DOMAIN

註釋The terms "bindweed" and "wild morning-glory" are rather indiscriminately applied to the various species of the genus of plants known by botanists as Convolvulus that are of importance as weeds. In certain limited sections other common names are used to refer to these species, such as gopher vine, pea vine, and wild sweet potato. By far the larger number of these plants are classified under the two species Convolvulus sepium and C. arvensis, the former a native of this country and the latter an introduction from Europe. There are a few other species, principally Convolvulus sepium repens and C. Californicus that occur as weeds in certain regions. The former is a variety of Convolvulus sepium, but is often referred to as C. repens. In many parts of the country these species rank among the worst of all the weeds that trouble the farmer, and in some regions they are by far the worst. Being perennials, the propagate not only by their seeds, but also by their underground parts. It is the latter character especially that makes them such formidable enemies to the tiller of the soil. The common or cultivated morning-glory, with the large bell-shape flowers of various colors, is sometimes found in fields where it has escaped cultivation. This is an annual not difficult to control and should not be mistaken for a species of convolvulus.