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Show DISEASE OF CABBAGE Infected Plants Show Tendency to Wilt on Sunny Days. Club Root Is Spread From Field to Field by Being Carried on Cultivators Cultiva-tors and Feet of Horses Rotation Ro-tation Is Suggested. (By H. S. REED, Virginia.) When a field Is badly Infected with diseaBe It may appear at the seedling stage, as a dwarfing of the young plants, but the fields are not usually "Oadly enough infected the first season to manifest the disease until the cabbage cab-bage is half grown. In districts where the disease has just begun to get a foothold, the grower is not likely to notice any trouble, therefore, until after the first of July. At about that time It will be noticed that the plants which are being Infected show a tendency ten-dency to wilt on bright sunny, days, although at night they may recover and do not wilt on the following day unless It is again bright and warm. Such plants may Bucceed in making enough growth to produce a salable cabbage, although It Is somewhat undersized un-dersized and slightly loose. The earlier the plant is infected with the disease, the smaller is the head produced. The agent responsible for the club root disease is an organism belonging to the lowest orders of plant life, w.hlch lives as a parasite upon the roots of cabbage and related plants, like cauliflower, rutabagas, flat turnips, mustard, etc. As the plant and Its parasite par-asite reaches maturity the latter ceases ceas-es active growth and begins the formation for-mation of spores which are capable of retaining their vitality through the winter and propagating the disease. The decay of the cabbage root accomplished accom-plished by bacteria and other forms of life, sets -free these spores in the soil, and there they remain until the following spring, when conditions are again favorable for growth, these spores germinate, giving rise to an active organism which is capable of again Infecting a plant. In this way A Well-Developed Case of Club Root. the cause of the disease perpetuates Itself in the sofl and each y-iar Injures the cabbage which Is planted there. The disease is spread from field to field by being carried on cultivators and the feet of horses, soil erosion, and by throwing diseased cabbages to stock on pasture. Guard carefully against introducing any material into a field which may carry the germs of the club root from diseased fields, and especially against diseased soil and diseased cabbage plants. Practice crop rotations which will allow at least three years between crops of cabbage, rutabagas or turnips. tur-nips. Apply stable manure to the crop which precedes cabbage, but not to the cabbage crop. If acid phosphate is used the same rule would hold. Lime will more successfully counteract the club root disease than other substances. sub-stances. Apply it at the rate of 100 busiels or more per acre, one or two years previous to planting the cabbage. |