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Show GERMAN TREE PESTS Electric Search Beams Lure Moths Into Heath Traps. Measure Msde Necessary by Ravages ot Insects Known as "Nuns." Which Threstened to Destroy Jenifers of Bason Forests. Oerlln. The foresters of Germany lure noxloua Insecta to their doom by the use of electrlo lights and other fiery attractions. The experiments of tho foresto.-s were made neceassry by the ravages of moths, known popularly throughout through-out Germany as the "nuns," which threatened to destroy the conlfera of the foresta of Saxony. The moths In question are coat active ac-tive between tho hours of 10 p. m and 1 a. m., and they are then attracted powerfully toward sources of light experiments demonstrated that the "nuns" were attracted by the fame of burning wood; more atrongly by acetylene ace-tylene or magnesium lamps, and- moat powerfully by the electrlo arc. The alluring of the moths waa accomplished ac-complished at Zlttau by co-operatlou between the foresters and the municipal munici-pal electric works. The entire stork of are lamps waa linked together, after aft-er the globea had been removed, and set In activity after nightfall. Although the forests were several miles distant the effect of the total Illumination waa audlclently strong to attract vast swarms ot moths from their leafy shelter They fluttered about the glowing carbons and quantities fell to the earth with singed wings. Although groat numbers were permanently dls-sbled, dls-sbled, It waa evident that the destructive destruc-tive factor nust be greatly multiplied to attain appreciable reaults. Fur that rvasun another plan was tried. At 11 p. m. the street lights were turned oft. ICIectrlc searchlights with a current of 40 amperea were mounted and their powerful raya were directed upon the neighboring lorests These searchlights exerted great attractive at-tractive force, which waa Increased by lluklng to each two arc lamps with globes. Ilelween these two lampa a powerful auction ventilator was stationed. sta-tioned. A piece of wire netting waa placed opposite the outlet of the von tllator a few nrhea distant The reaults were etarlllng. The moths enme from the forests In enor mous numbers and sooner or later were sucked Into the ventilator and hurled by It agulnst the wire netting with such force that the wings were broken and tho Insects rendered help less or killed outright. r'our of these devices were Installed In the town ot Zlttau on the roofs of buildings. A few minutes after the searchlight la turned on scattered moths appear. Then the number rap Idly Increases until thousands arrive simultaneously and flutter In and out ot the great beam of light kjteadlly they near Its source until suddenly they are wllbln the grasp of the unseen suction of the ventilator; and In a accord they paaa through It and lull crushed and helpless to the bottom of the wire cage. The maximum maxi-mum result attained In a single night by this method was a total weight if Ml pounds, representing about 400,. OHO deud moths. The outcome of these experiments baa been so convincing that It will b continued on a nncb more extended scale. The officials of the United mates department of agriculture have been greatly Interested by the reports, aa the question of protection from Insects In-sects enemies of shade trees In New ICngland and of American forests generally has of late assumed much prominence. Experiments In America, It la reported, report-ed, along the lines laid down by the foresters of Zlttau will probably be un- f dertaken under the auspices of the d partment ol agriculture next year. |