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Show F ! I ENTOMOLOGY I Edited by Prof. E. G. Titus, State Agricultural College. SOME POINTS IN ECONOMIC ENTOMOLOGY. This Is a subject which is neither too scientific or too abstruse to be readily understood. In fact many farmers already understand the gen- cral principles underlying the correct application of the knowledge involved. Agricultural Entomology is to a: great extent agriculture, often more agricultural agricul-tural than entomological. How the farmer can apply a knowledge knowl-edge of economic entomology to the best advantage in his regular farm practice is what he primarily desires to know. The question asked is: What kind of economic entomology do I need and how can I best apply it in my ordinary farming operations? In the first place the farmer should know the principal insect injuries to which his crops are liable and how to recognize them when they occur. He should also be able, at least to some extent, to state what conditions are likely to allow certain injuries to oc- Icur. A crop may suffer insect injury from the time the seed is planted until un-til we are eating the manufactured product. Dr. S. A. Forbes, State Entomologist Entomolo-gist of Illinois once aptly summarized this as follows: "The corn crop may suffer injury from the time the see! is fa tlie cmuwd Iftttil tkfe atfsfcl is in the .mush-bowl. The planted kernel may be eaten by wircworms or the sccd-corh maggot, and the young plant may cease to grow (because its roots arc being devoured by the wircworm or the white-grub, or because the sap is being sucked from them by the corn root-aphis. Its soft stem may be burrowed bur-rowed by the stalk-borer, or pierced by bill-bugs, or cut off by cutworms. Its young leaves may be eaten by the cornworm, which later may mine through the kernels beneath the still green husks. The whole plant may . fo-c devoured by the armyworm in May or June, or it may be so blackened black-ened by chinch-bugs in June or July, as these insects come out from adjoining ad-joining fields of 'ripening wheat or oats, that it withers and dries up under un-der the myriads of their tiny beaks as if it were scorched by fire. When it has grown tall and strong it may weaken and fall to the ground because its larger roots have been mined by the corn root-worm or eaten away by the ever present white-grub, or because be-cause the development of the brace-roots brace-roots has been prevented by chinch-bugs chinch-bugs sucking away the sap from the crown of the plant; and when its noble product has been harvested, the ear in the crib may be peppered with the shot-holes of the grain-moths and their like, and the meal in the sack may be made offensive and unwholesome' unwhole-some' by the meat-w"dtm ' or the cn-defle." Fortunately wc have no crop at the present that is quite so seriously troubled as corn is in the East. However, How-ever, wchavc many crops that have . each of them insects injuring one or more stages. Our grass and grain crops, sugar beets, corn, vegetable crops, fruits, all arc liable to certain ' injuries, some of which wc can quite easily recognize and control. The most of the more common injuries the up-to-date farmer will readily recognize, re-cognize, token together this knowledge knowl-edge is important and practical. Much of it can be picked up in the course of practical farm work and by observation, ob-servation, but much more will need to be gathered by study, reading and from the experience of others. The farmer needs to know some facts and some entomological language lan-guage in order o be able to understand under-stand the statements made by entomologists ento-mologists concerning their especial studies. The more important orders of insects, the greater divisions as it wcref should be known. He should be able to recognize a butterfly from a moth, a bee from a beetle. All insects in-sects are not properly called "bugs"; the plant-lice or aphids may be so called, but the grasshopper belongs to an entirely different order. Some other important things are to know which orders of insects have biting .mouthparts and eat solid foods like leaves and roots and which insects have sucking mouthparts taking as their food the sap of plants or blood of animals through a beak. There are some wonderful facts connected with the life of insects; we would' all consider it a woVderful thincr if some of our domestic animals H should after they arc born, during H their younger life have, biting mouth- H parts and then later pass intp a, resting H stage and come out with sucking H mouth-parts, yet that is what hap- pens with all the butterflies and moths. In many orders" of insccti the young insect when first hatched from H the egg is obviously so like the full H grown that they arc reo-dily recog- H nized as 'belonging to that group. For H instance the young grasshoppers are H much like the adults, but have not wings with which they can fly. Wc H call the younger" stages of such in- H sects (grasshoppers, aphids, truebugs H and others nymphs), and regard their H transformations as incomplete; they H having but three distinct stages, egg, H riymph (during which the young in- H sect feeds, and several times casts H off its skin as it grows" iriv size) and H the adult stage. The bees, beetles, H butterflies and a number of other in- H sects have what is known as complete H transformation; that is four stages: K gg, larva, pupa and adult. The stage H : called larva is" the younger stage in H which as in the nymph the insect H feeds and several -timc.5 casts its skin, !H but during this stage the insect at H no time looks like the adult insect H that laid the egg; the common cut- H worms, the white grubs and such H forms nil belong in this stage. The H pupa stage is the resting stage in H which the insect does not feed, but H passes from the larval form to the H adult, coming out of the pupa as a fl winged full-grown fnsTect;' a'bVe to re- H produce its Icimo. H |