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Show Emergency Control Methods For Weevil In Alfalfa Fkl By W. W. Owens, U. S. A. C. Extension Service (Editor's Note: Tills is the fifth rt a series of seven articles pre-recl pre-recl by Mr. Owens, for this paper, on weevil control.) Dusting or spraying with calcium calci-um arsenate is the best emergency Tthod of control . when weevils ave become so numerous that thej" are checking the growth of alfalfa. Arsenic poison sticks on ?"e growing plant in large enough quantities to kill the worms when they start to eat the leaves and "orchard spray machines may be used to spray the alfalfa xhey should be able to maintain a minimum of 75 pounds pressure. A boom attachment can be made, from one- half inch iron pipe Nozzles Noz-zles should be selected which will give a mistv spray. Two pounds Of calcium arsenate should be used fcr each 100 gallons of water and this mixture applied at the rate of 100 gallons per acre. Care should be taken to avoid spraying any part of the field several times. One spraying will kill the weevil and does' not make the hay harmful livestock. If a machine is to be purchased especially for weevil control, a dusting machine rather than a sprayer should be considered. A power duster capable of covering eight acres per hour can be purchased pur-chased for about $250. For many Utah farms a hand duster will suffice. Such a machine capable of dusting one acre per hour can be purchased for about $15. Calcium arsenate so finely powdered that no grit can be felt between the fingers, fin-gers, should be applied at the rate cf 2 K pounds per acre in dusting, preferably mixed with an equal quantity of dusting sulpher. Where dusting or spraying is nit possible, alfalfa which is standing still or even going bad; becav.s? of excessive weevil damagr, should be cut and removed from the field as quickly as possible The ground should then be thoroughly thor-oughly stirred with a springtooth, to be followed by a wire drag made by putting net wire or barb wire under the backward tilted teeth cf a harrow. Leave the soil in this dusty mulched condition for two days and then irrigate. Due to the increased labor expense, th? less of hay, and the difficulty ol securing irrigation water at the proper time, the draggng method of weevil control is only recommended recom-mended as a last resort. As a precaution in areas where weevil damage is probable this year, every farmer should find out where he can get a machine on short notice for dusting or spraying. spray-ing. He should know where he can socure the calcium arsenate. The county agent will give ,t this regard. S 6 tanc; k Dusting, spraying and . are .emergency control J They are necessary L5eaW when cultural control have not been followed weather is encountered nas'JS method of insuring prow S gainst weevil damage h tl , cultural methods of ea-, prac of alfalfa as outlined in , article. 1 Pi Next Artcle: The Alfalfa has Enemy in Pamites 3J State. c es Sent t( |