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Show ALFALFA WEEVIL SEEKS NEW TERRITORY ( (Prepared by the United States Department Depart-ment of Agriculture.) The alfalfa weevil, which, since its accidental introduction into the United States in 1904, has been confined to alfalfa fields in the great basin of the West, has now spread beyond the limits of this natural division and is advancing so steadily, in spite of efforts ef-forts made to combat its movement, that entomologists of the United States department of agriculture fear that sooner or later every section of the country will be invaded by the pest. The spread of the weevil outside the great basin has been north into portions por-tions of Idaho lying in the Snake river drainage system and south into portions por-tions of Utah lying southwest of the continental divide. Though entomologists entomolo-gists of the department look on the spread of the weevil across the continental conti-nental divide as denoting the passing of a landmark rather than as the surmounting sur-mounting of a barrier, they point out that the pest is, nevertheless, many miles nearer to important alfalfa-growing districts which have hitherto felt safe from attacks by the insect. Description of Weevil. A description of the alfalfa weevil and method of combating its ravages are contained in a new publication of the United States department of agriculture, agri-culture, Farmers' Bulletin 741. The spread of the pest has, as a matter of fact, been slower than was at one time feared, but its progress lias been steady. In Utah and in small portions S 1 ' V ' t K" x y V , ' , ' Ji Spray Pump in Use. of Idaho and Wyoming, where it now exists, it has caused at times a loss of o0 per cent of the first cutting of alfalfa al-falfa and a total loss of the second cutting. In order that farmers In those sections sec-tions in which the weevil has not yet appeared may be able to recognize the pest and to protect their crops from it, the bulletin already mentioned contains details -of its hubits and of its appearance in the various life stages. The weevil is most easily discovered dis-covered in the form of the full-grown larva. It is then a green wormlike denture one-fourth of an inch long with a black head and a faint white stripe down the middle of the back. It feeds upon the leaves of the alfalfa mainly during late May, June and early July and may be found by sweeping the tops of tlie plants with an insect net or by looking for the notches in the leaves where It lias fed. When the larvae are numerous they destroy most of the tender growth and cause the tops, to appear white, making the held look tis if frostbitten when viewed from a distance. The adult insect is an oval, brown beetle three-sixteenths of an inch long, with a prominent snout. Its color frequently fre-quently is nearly black. This beetle is harder to discover than the larva, but, oil the other hand, it is present in the field the whole year around. In winter It can be found by digging around the crowns and roots of alfalfa plants. Control Measures. The alfalfa weevil does not hibernate hiber-nate definitely. When the weather is cool the adults are quiet, but with warmer temperatures they quickly resume re-sume their activities. Egg laying begins be-gins in early spring, and is usually ended by June 10. One efficacious method of controlling the pest, therefore, there-fore, is to destroy the eggs by pasturing pas-turing the first crop up to that time. A similar result may be obtained by cutting the alfalfa green and feeding it as a soiling crop. If this is not done the larvae hatch in large numbers about the last week of May or earlier, and eat the alfalfa leaves so rapidly that the plant Is unable un-able to outgrow the injury. After the field is cut the larvae which have been feeding upon the first crop gather upon the buds of the stubble and frequently fre-quently consume all of the second crop. By that time most of the insects have completed their growing period and have gone into the pupal or resting rest-ing stage. The later growth of the crop, therefore, does not suffer from them. To protect the crop pasturing, it has been said, is effective in the early part of the season. The field should be divided into two or three lots and each lot should be pastured alternately, alternate-ly, the animals being left in it until the alfalfa has been eaten clown close to the ground. The number and size of the lots should be proportioned to the producing power of the field and the number of animals to be pastured, so that each lot may be grazed about once in tsvo weeks. Pasturing should be continued until most of the weevil eggs have been laid, which, in practice, prac-tice, means a little later than the usual cutting time of the first crop. This method has the additional advantage of providing an economical method of fattening live stock. Combined with the proper feed of grain, alfalfa pasture pas-ture is excellent for putting on weight and it is said that many farms would probably be more profitable if their management centered about the pasturing pas-turing of stock on alfalfa with the growing of enough other crops to provide pro-vide grain and forage throughout the year. If the weevils are not killed early In tlie year they may be destroyed after the first crop has been removed by getting get-ting rid of all the vegetation in the field, crushing the clods, and fining the cracks so as to expose the entire surface sur-face to the sun. This is best done by covering the field with a dust mulch, the dust being an additional means of killing weevils. Success obviously depends de-pends upon doing the work when the ground is dry and the weather warm and bright. The second crop may also be protected protect-ed by spraying the stubble. Spraying may also be resorted to in the spring. From 50 to 100 gallons per acre of a mixture of arsenite of zinc and water in the proportion of 4 ounces of powder pow-der to 100 gallons are used for this purpose. The apparatus best suited for alfalfa spraying is described in detail in the bulletin already mentioned. men-tioned. Still another recommendation made in this bulletin is the stimulation stimula-tion of the growth of the alfalfa by cultivating the field in the spring. Tills does not destroy the weevils but it serves to produce a larger and earlier ear-lier yield when their attacks make early cutting necessary. L'p to the present, however, more farmers are concerned with preventing prevent-ing the alfalfa weevil reaching their fields than they are with controlling it in them. No one knows exactly Low tlie weevils spread, but certain facts in regard to this matter have been ascertained. It is known, for example, exam-ple, that the insects are oftnn found in green alfalfa fresh from itie field and in second-crop hay and among potatoes po-tatoes which have been in contact with it. They are found also in cured alfalfa hay, especially that of the second sec-ond cutting. Potatoes often are hauled in cars upon a bedding of green alfalfa al-falfa hay and there is danger that the weevil may be transported in this way. On the other hand, however, there is no evidence to show that tlie weevil spreads more rapidly along rail-loads rail-loads than elsewhere. |