In other cases causing prolonged and a more or less partial injury. These grubs are also extremely destructive to grass lands, in some cases causing complete destruction of the sod. The adult beetles also frequently cause considerable injury by feeding upon the leaves of deciduous trees. No thoroughly satisfactory remedy has yet been proposed for this insect.

331. CORN ROOT WORMS.-There are two species: the western corn root worm and the southern corn root worm. The larva of the western corn root worm is two-fifths of an inch long, about as large as a pin, body somewhat cylindrical, colorless, except the head, top of the first segment and a little patch on the last segment of the body, which are yellowish-brown. The injury is done by the larva, chiefly during July and August, by beginning in the tip of the maize root and working towards the plant, devouring the inner portion of the root as it goes. It pupates in the earth among or near the roots of maize. The pupae emerge in August or September as grass-green beetles about one-fifth of an inch long and half as wide. The beetles feed upon the pollen, silks and in some cases upon the soft grains at the top of the ear, but usually the injury done by the beetle is trivial. The beetle lays clusters of five to a dozen dirty-white eggs one-fortieth of an inch long in the ground, one inch to six inches deep, about the maize plant during October and November. Only the eggs survive the winter, hatching in May and June. The southern corn root worm is distinguished by the beetle being larger and 'having three transverse rows of four black spots on the wing covers. Since the larvae of these two species have no other host plant and since the eggs are usually laid about the hills of maize plants, a rotation of crops furnishes a simple and effective remedy for these insects. It is likewise destructive only in those sections where maize is cultivated on the same land several years in succession.

Western corn root worm, enlarged three times. (After Forbes.)

332. CORN Root Web-Worms.-They are the larvae of at least five species of moths which lay their eggs among the grass in the summer, the larvae passing the winter in a half-grown condition. They attack the young maize plant just above ground, and when not at work they remain in a silken web just underneath the ground at the base of the plant. The fully grown larva is about half an inch long, somewhat hairy, varying in color from brown to dirty white. They pupate about June first, on the fortieth parallel. They may also attack oats.1 Their injuries to maize may be avoided by late planting. Ordinarily, injury is to be expected only where maize follows grass; the longer the land has been in grass the greater the danger.

333. CORN ROOT LOUSE.-All plant lice are enormously prolific. During the summer the wingless females of the corn root louse reproduce continuously, without the intervention of the males, living young which, when a few days old, also begin to multiply. Winged females appear from time to time and establish new colonies, while in the fall large numbers of individuals of both sexes appear. Generally the last brood lays eggs from which the spring brood is produced. Ants apparently

a Ohio Bul. 68, p. 48.

protect and care for the plant-lice in return for their secretions which they consume. They are held in check by carnivorous and parasitic insects. The corn root louse does its greatest injury to the young maize plant during May and June, causing the

$

Corn root louse on the left and its care. taker, the ant, on the right, both enlarged. (After Forbes.)

plant to wither and die by sucking its juices. Usually these attacks are in spots throughout the field and are likely to be most injurious during unfavorable weather conditions. The injury done by these insects is variable and fitful, owing, doubtless, to their great prolificacy and the enemies which keep them in check, so that remedial measures are usually of slight avail. The corn plant louse (Aphis maidis) attacks the plant above ground, but it appears to be less injurious than the corn root louse, whose attacks are confined to the roots.

334. CORN BILL BUGS.-Several species of bill bugs are known to be injurious to maize. The adults are black beetles one-fourth to three-fourths inch long, which do their damage by puncturing the stalks and the young leaves of maize as they are unfolding. Eggs are usually laid during the spring and summer and reach the pupal stage in about one month. In some species the larvae live in the interior of the stalk, bulb or roots of small grain or timothy, and in other cases in the maize plant itself. They pass the winter in the adult form. The damage is generally comparatively slight. There is no specific remedy.

335. CORN EAR-WORM.-The larva, one and one-half inches long, varies in color from pale green to dark brown, is marked with longitudinal stripes of the same color, with eight round shining black spots on each segment of the body from which arise short hairs; the head and neck are brown. It is two to seven-brooded, depending upon the latitude. The last brood passes the winter in the pupal stage, emerging as a moth in the spring. In the Northern States the most destructive brood lays its eggs in the silk when the ears are young, and the larvae feed upon the grains at the tip of the ear, often doing great damage, not alone on account of the grain actually eaten, but also through subsequent decay by access of moisture and through destruction due to other insects. In the Southern States the earlier broods are also destructive by feeding upon the leaves and stalks. This insect is injurious to cotton by feeding upon the bolls; hence is known as the boll worm. Disturbance of the pupa by late fall plowing or early spring plowing appears to be of some value, although no remedy has been found which is entirely efficient.

336. STALK BORERS.-There are at least three species of insects which injure maize by boring in the stem, although they are often equally injurious to other plants, including weeds; namely, the stalk borer (Gortyna nitela Guen.), the smaller stalk borer (Pempelia lignosella Zeller) and the larger stalk borer (Diatraea saccharalis Fab.). The most serious injury is usually done by the latter, which in the South Atlantic States occasionally amounts to twenty-five to fifty per cent of the crop. I U. S. Dept. of Agr., Div. Ent. Cir. 16, 2d Ser.

The larva is three-fourths inch long, white and marked with dark brown spots. It bores the stalks of young maize, seriously injuring it, and later bores into older stems, working down into the tap root, and passes the winter in the pupal stage in a channel about the surface of the ground or a little below. The moth issues in the spring, soon to lay eggs near the base of the leaves. It also attacks sugar cane and sorghum, as well as gama or sesame grass (Tripsacum dactyloides), and consequently is more likely to be a dangerous pest near swampy lands, where this grass grows. Clean culture and systematic rotation of crops is a fairly effective remedy.

OTHER ENEMIES.

337. THE CROw.-In many sections, especially where maize is planted near clumps of timber, the American crow (Corvus Americanus And.) pulls up and eats the young plant, often causing considerable damage. Most of the preventive measures recommended have for their basis methods of frightening the crows away until the plants are large enough to resist their attacks. Among these measures are the simple scarecrow, trapping the birds alive and keeping them tied in the field, and poisoning a few with maize grain soaked in strychnine as a warning. Coating the seed slightly with coal tar is sometimes quite effective. This may be done by dipping a wooden paddle into the hot liquid and then stirring it rapidly among the maize grains. There is some danger of decreasing the germination. It is generally conceded that except for this annual depredation the crow is useful to agriculture as a destroyer of insect pests.

338. THE AMERICAN BLACKBIRD (Agelaius phoeniceus Linn.) occasionally does somewhat serious damage by feeding upon grain while it is still soft.

339. THE STRIped Prairie SQUIRREL (Spermophilus 13-lineatus), especially in sections from Illinois westward, frequently makes replanting necessary by digging up and consuming the sprouting grain. Gillette has shown that injurious insects constitute a large proportion of its food. It is believed that these squirrels are not only beneficial to meadows and pastures, but to subsequent maize crops, because of their destruction of cutworms, wireworms, web-worms and similar insects.

XVI.

MAIZE.

1. HARVESTING AND PRESERVATION.

340. Harvesting.-Although there has been considerable progress in the harvesting of maize, no such profound changes have been made as those noted in the harvesting of the small grains. The larger part of the crop is still husked by hand from the standing plant and cattle allowed to roam over the husked fields to pick up neglected ears and nubbins, and to

feed upon the leaves and husks. Attempts to husk the standing maize by machinery have not met with success.

341. Storing.-After being husked, the ears of maize are stored in ventilated (slatted) bins, called cribs, in order that the excess of moisture may evaporate

built upon the platform by the ma- before the grain is shelled. (233)

chine, after which it is raised by the derrick and placed upon the ground,

next round.

While on the ear, the grain is not out of the way of the machine on its readily injured for feeding purposes by exposure to atmospheric conditions, but when shelled is subject to heating and molding, if not thoroughly air-dry. A difference of two per cent in moisture content may materially influence the keeping quality of the shelled grain.

When maize is stored in the ear, it is particularly subject to attacks from rats and mice because of the facility with which these vermin may pass between the ears. Special precautions

should be taken to reduce their ravages to a minimum by raising the bottom of the crib from the ground, thus reducing their hiding places as well as giving access to cats and dogs.

342. Maize Fodder.-In the North Atlantic and Southern States, and in portions of the North Central States, most of the maize is cut and put into shocks or into the silo. This cutting may be, and for the most part still is, done by means of a corn knife, although the corn cutter and the corn harvester are both largely used, the latter especially where maize is cut for the silo. A machine has recently been invented which cuts and shocks the maize at one operation, but its use has not yet become general.

From 5x7, or thirty-five hills, to 12x12, or 144 hills, are placed in a single shock. The lesser quantity is common in the North Atlantic States, where, according to the Connecticut Station, it is more difficult to preserve flint stover, while ten hills square, or 324 shocks per acre, is the common

Maize harvester. Cuts and binds plants into bun

amount in the North Central States. A common method is to tie four hills together without cutting them off and then to shock the rest of the

dles, which may afterwards be put into shocks; plants around these; while

also very useful in harvesting maize for silage.

in other cases a wooden When the shock is com

horse is used as a temporary support. pleted, a light rope with a hook on one end is used to draw the top of the shock together, when it is tied with twine or in some