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Show The Eel Worm Disease a Menace To Alfalfa in America (Continued from October Issue) Cause of the Disease. The organism that causes (.he disease is an eelworm or nematode technically known as Tylent'ius a small round worm, scarcely of an inch long when It maltiuiies by fully grown. means of eggs, as many as 200 being laid by a single individual. The or larvae., newly hatched young, are the same shape as the adults but only about as large. Under moist conditions these larvae migrate or are carried by irrigation water or other means to new plants. Penetrating the .plant through tender succulent parts, they grow to maturity within the plac,t tissues. Their presence there acts as a stim- ulation which causes the swellings and abnormal and development, their parasitic action robs the plant of ' its power to produce a strong A single swollen stem or growth. sprout may contain hundreds of eel-- ! worms, each deriving its food from the plant. Finally the nematodes become so abundant as to complete-- 1 ly kill the plant. They then leave it arjd migrate into the soil, ready to attack other plants which they may be able to reach. This eelworm is distinctly different from the one which causes root-knin a wide variety of plants and abnormal swellings on potatoes arid The alfalfa other tuberous crops. eelworm occurs only in the aerial parts of the plants. Manner of Spread. The organisms may be carried long distances by irrigation) water or by hay. Waste water from infested fields carries the organisms It may empty by the millions. into a ditch that does duty lower down on the same farm or on an adjacent farm, or it may go back irto a large lateral ditch or even a river, and thus be carried to another irrigation project miles away. In vhay the gaoisms show their remarkable resistance to drying. Stems of alfalfa hay, cured under normal conditions, with typical eelworm swellings and of which specimen stems were photographed five months after they were cut had living nematodes recovered from them, and when used to inoculate alfalfa plants in the greenhouse they proInfested duced the typical disease. hay, therefore, is art important carrier of the disease. The spread over shorter distances may be accomplished by farm implements, which probably play a great part in carrying infection to all parts of the farm from small centers of infection, or by animals, birds, man, or wir'd, any one of which may carry a bit or soil or mud or bits of disposed plants containing many eelworms or their eggs. be destroyed as well. After doing the work of eradication of alfalfa in an affected all tools and implements shouldfield, be thoroughly cleaned and disinfected. Hot water or a direct a torch of some kind, flaming with momentarily applied, is the surest way to kill any nematodes or their eggs that be sticking to the implements. may If this is done, the tools may be used anywhere without fear of carrying the disease. It must be kept in mind that fields that had diseased alfalfa contain the living organisms in the soil. Consequently, spread from such fields by implements or use of waste water must be guarded against for two years on more. di-psa- ci, one-twentie- th one-ten- th wnnsBaaaaMHEX.3BX23aB j j ot ' Alfalfa Seed Growers The Western Seed Marketing Company are in the Market at all times for seed of alfalfa and clover. I Highest Prices Paid We have a Constant Demand for Hardy, Western Grown Seed. All our Seed Goes to the Consumer in our Branded and Sealed Bags. We Advertise and Handle Only Western Grown Seed. efore You Sell Get In Touch With Us Means of Control. In this case an ounce of prevent-tioIt is is worth a ton of cure. worth any effort to prevent the first Avoid-- 1 infection from occurring. of means various spread ing the mentioned above is one way to do this. Some of the means, such as transmission by wind or birds, can rot be controlled. The safest way especially from the point of view, of the owners of the millions of acres that are free from the disease, is to eradicate the disease where-eve- r This will involve it occurs. plowing up the affected fields and devoting them to other crops for at This gives sufleast three years. ficient time to starve the organisms The removal of alfalcompletely. fa must be complete, however; otherwise enough of the organisms will be held over alive to bring about new centers of Infection when alfalNot only fa is again planted. must all volunteer alfalfa plants appearing in) the field after the plow-on ing be grubbed out, but those the ditch banks and fence rows must ' It is recognized that difficulties i the alfalfa eelworm. Some weeds are involved in putting these sug- are aso subject to infection). The gestions into practice. They can, entire list of possible hosts has not however, be carried out, and these been ascertained in America. are the only methods which are now yet From the results already secured, regarded as effective. Further however, the alfalfa eelworm disease of methods of eradica- aside from its seriousness on that tion are needed and are in progress. crop alone, appears to be a menace The direct sterlization of the soil by to agriculture which should be met the application of chemicals or heat promptly by strenuous measures. An may be practicable in very limited attempt should be made to spot all infestations, but experience gained infestations and to at once eradicate in work on the potato wart indicates the disease, a thing which is very that such treatment is highly expen- possible of accomplishment unless it sive and of doubtful efficacy when is already too generally established-I- f applied to large areas. this is done, the immense losses The Disease a Possible Menace to due to reduced yields and to the need for more frequent plowing up Other Crops. A further reason) for prompt and and replanting, such as occur in aggressive action in dealing with South Africa, may be avoided. this disease is the fact that the causIt is requested that specimens of al organism may under favorable suspected material be sent in promptconditions pass over to and ' affect ly to the Bureau of Plarjt Industry, other crops. In a small experimen-ta- l United States Department of Agriway, red, white, and alsike clov-- I culture, at Washington, for identiers, buckwheat, rye, Erglish pea, fication, together with an account of turnip, and even potatoes have been the extent to which the disease attacked and definitely injured by n j I j P. O. Box 180 B. F. SHEEHAN My ton, Utah FRED BURGER |