Arizona republican., 1918-11-01
Fumigation Of Craneries
By A. W. Morrill,, State Entomologist

At this season stored grain is ire | quently severely damaged by several grain beetles and WeeVils, also a spe cles of moth, which insects not only l consume the substance of the grain but in some cases give it a flavor which is objectionable to stock. The l Ninth Annual Report of the Arizona Commission of Agriculture and Horti- culture includes a brief account of the damage done by insects at a farm l granary near Phoenix in the fall ot | 1917, together with an account of the methods employed in fumigating with carbon bisulfid This circular is pre- pared to give information concerning this method of control so that it may | be more generally used by farmers and seedsmen in Arizona
 1 Carbon bisulfid is a clear liquid which when exposed evaporates or volatilizes very rapidly forming q poisonous gas. This gas is about two l and a half times as heavy as air. When mixed with certain proportions of air 1t is highly inflammable and explosive. On account of it's penetrative powers carbon bisulfid gas is very effective | against insects in stored grains and other food products. It is commonly called Thigh life" and is well known in some sections on account of its use against prairie dogs. The chemically pure carbon bisulfid does not have an objectionable odor but the commercial grade manufactured particularly for | the destruction of insects and rodents | has a disagreeable odor owing to hy- drogen sulfid which it contains.
 Make Building Tight
 | In fumigating a granary the first step is to make the building as tight as possible. The bottom can usually be made reasonably tight by throwing dirt all around the sides and packing it down with a shovel. Strips of heavy brown paper should be pasted over all cracks and openings in the side walls | It is, as a rule, best to employ pro- fessonal paper hanger to do this. One door should be left open as an exit, but everything should be in readiness for prompt work as soon as the operators have finished their work inside. Wet newspapers are useful in preparing a building for Immigration, especially in closing openings around sliding doors
 The wet paper should be tightly rammed into the openings with { stick. If the roof is provided with g Ventilator one or more wagon or hay stack covers may bethrown over 1t 1T order to check the circulation of air
 All openings should be covered for as far as possible above the highest sacl of grain but a margin of three or foul feet proved sufficient in one instance where it was impractical to close { corrugated iron building tightly at thu caves. Sometimes it may be necessary to rearrange the sacks of grain il order to have all of it well below tho caves.
 Start About Noon
 The exposure should start prefer ably about midday since insects art easiest to poison when most active anC up to certain point they are mos active when the temperature is high est. Do not fumigate when the tenn
 perature is below 70 degrees. Tn
 granary should be kept closed fo twenty four hours by which time mucl of the gas will have escaped.
 Carbon disulfid will not injure tn
 feeding value or the examination o