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Show ENEMIES OF ALFALFA Leaf Weevil Has Ruined Many Fields in Utah. Utah Experiment Station Issues Bulletin Bul-letin Dealing With Pestiferous Insect How It Was First Brought to This Country. Alfalfa is a great friend' of the farmer, but like other friends It attracts at-tracts enemies as it spreads. As potato po-tato culture developed Insects and disease dis-ease followed and multiplied, as apple orchards accumulated in any section, Insects peculiar to apple trees became pests. So It seems to be with alfalfa. In Colorado grasshoppers followed alfalfa development until they are a regular plague. In Utah the alfalfa leaf-weevil has appeared in such numbers num-bers that it has ruined many old .fields. The Utah experiment station has Issued a bulletin dealing with the I winter as an adult beetle In any wet ' sheltered place. When the alfalfa starts they come out and begin laying lay-ing eggs within a few days. These eggs natcn m seven to sixteen days and the other changes in the life ol the insect follow. The insects cut holes or slits in the aifall- stems, or at the base of the leaves where they lay the eggs, and this cutting and gouging ruins the plant, and in many cases this means a loss of from 40 to 90 per cent, of the crop. ,The young insects also feed on the plants and do great damage. The insects are worse where the alfalfa al-falfa is left a long time without re-plowipg re-plowipg and seeding. In Utah, where irrigation is given, the alfalfa fields sometimes stand 30 or more years, and these old fields are badly affected. affect-ed. In the east where alfalfa will probably be used as part of a long rotation ro-tation it Is not likely that the insect will do great damage. In Utah measures meas-ures for fighting the insect have In mind the plan of preventing Its feeding feed-ing when it first comes through winter win-ter and then tearing up the soil lightly light-ly with a heavy dust to destroy the in- Brush Harrow for Alfalfa. Insect. It is a native of Europe and is probably found wherever alfalfa Is grown, although Mt is not troublesome trouble-some except in sections where the crop has become an extensive one. it feeds on alfalfa and on six varieties of clover, including red and crimson. It is probable that the weevil was first brought to this country in hay or straw used in packing crockery or nursery stock. It has no doubt been in the Atlantic states for some years, but has not become serious, since alfalfa al-falfa is not largely grown. It seems that many western fruit orchards are surrounded by fields of alfalfa or sweet clover. The insects crawl into the fruit packages, and are in this way carried about. They also travel In hay or feed, and in this way are distributed. The insect passes the sects and drive them away. Thus the field may be worked lightly with the disk harrow and then watered at once to rush the alfalfa into growth. In several cases close pasturing and dragging has proved helpful. Horses or sheep were turned in to keep the alfalfa eaten close. During this pasturing pas-turing the field was worked at leasf once a -week with a brush drag or a sweeper. A picture of the brush drag is shown. This is made by laying the butts of short brush five or six feet long on a plank 12 or 14 feet long, with other rows of brush shingled on the whole thing weighted down by a tooth harrow with the teeth down directly on the brush drag. This drag knocks off many weevils and kills them, while the thick dust suffocates more. |