Report of the Commissioner of Agriculture |
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acre albuminoids Amber American amount analyses animals annual appearance August average Barley Buckwheat bushels cabbage CABBAGE WORMS cane cattle cent cental cocoons color Colorado condition cows crop cultivation Department of Agriculture destroyed disease eggs Europe experiments exports farm farmers feeding fiber flesh flour flower forests fowl cholera fowls gallons glumes gluten grain grass growth hackmatack head Illinois inches increase Indian corn Indiana infected inoculated investigations juice July June Kansas land larva larvæ leaves less locusts lombriz meat Minnesota Mississippi Missouri nearly nitrogen North Carolina Oats Ohio Oregon panicle Paris green pastures plants Plate Plusia Potatoes pounds present pupa Pyrethrum quantity season seed sheep soil sorghum South species specimens spikelet Strongylus sucrose sugar Tennessee Territories Texas fever tion Total trees Virginia virus weight West wheat winter worms Yellow yield
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Trang 152 - Heat the solution of soap, and add it boiling hot to the kerosene. Churn the mixture by means of a force pump and spray nozzle for five or ten minutes. The emulsion, if perfect, forms a cream, which thickens on cooling, and should adhere without oiliness to the surface of glass. Dilute before using one part of the emulsion with nine parts of hot water. The above formula gives three gallons of emulsion, and makes, when diluted, thirty gallons of wash.
Trang 147 - Moreover, as we have seen in the case of the attacks of the larch worm, the defoliation of spruces and firs repeated two and perhaps three summers is sufficient to either kill the tree outright, or so weaken it that bark-boring beetles can complete the work of destruction. We are now inclined to the opinion, then, that the Bud Tortrix is the sole or at least main cause of the destruction of spruces and firs in Cumberland...
Trang 166 - Effects of the Poison. — In this grove the elms that were poisoned in 1882 were attacked in the spring of 1883 less severely than were those which were not poisoned the previous year. This would seem to imply that the insects deposit mostly on the trees nearest to where they develop, and are only partially migratory before ovipositing.
Trang 148 - Fernald observes, eat the shell. They hatch about or soon after the middle of July, and it is most probable that the caterpillars become partly, perhaps almost wholly, grown before the end of autumn, and pass the winter among the terminal shoots of the tree, to finish their transformations the following June and July. It is certain that there is but a single brood of caterpillars. Professor Fernald, in his article in the American Naturalist, describes the process of egg-laying.
Trang 165 - ... not killed off thoroughly for several days, and in all cases it requires considerable time to attain the full effect of the poison. This result appears on the plant and on the insect. After each rain the poison takes a new effect upon the plant and the pest, which indicates that the poison is absorbed more or is more active when wet, and that it acts by dehydrating thereafter. Where the tree is too strongly poisoned, each rain canses a new lot of leaves to become discolored by the poison or to...
Trang 166 - This would seem to imply that the insects deposit mostly on the trees nearest to where they develop, and are only partially migratory before ovipositing. The attack afterward became increased, probably by immigration and the new generation, so that later in the season the trees were mostly infested to the usual extent. In the region of Washington a preventive application of poison should...
Trang 174 - Some of the earlier-laid eggs hatch in autumn, so that there is the same tendency toward a second brood as we find in spretus, a tendency which is more marked during a warm, protracted autumn, and which is beneficial to the farmer, inasmuch as all these autumn-hatched individuals invariably perish during the winter.
Trang 173 - ... tapering more suddenly and by the two lobes forming the notch being less marked. From both species it is distinguished not only by its smaller size but by the deeper, more livid color of the dark parts, and the paler yellow of the light parts — the colors thus more strongly contrasting.
Trang 154 - It consists of a shallow, circular, metal chamber soldered to a short piece of metal tubing as an inlet. The inlet passage penetrates the wall of the chamber tangentially, admitting the fluid eccentrically, and causing it to rotate rapidly in the chamber. The outlet consists of a very small hole drilled in the exact center of one face of the chamber. The orifice should not be larger than will admit the shaft of an ordinary pin. Through this outlet the fluid is driven perpendicularly to the plane...
Trang 154 - ... the wall of the chamber ta.ngentially, admitting the fluid eccentrically, and causing it to rotate rapidly in the chamber. The outlet consists of a very small hole drilled in the exact center of one face of the chamber. The orifice should not be larger than will admit the shaft of an ordinary pin. Through this outlet the fluid is driven perpendicularly to the plane of rotation in the chamber. Its whirling motion disperses it broadly from the orifice, and produces a very fine spray, which may...