m&oiar no. so, Secono Series. mini States Departmenl oJ DIVISION OF BNTOMOLOOy! MIX Bl PI U o I Kl I .lliil'Hi'K. hov ura. : r B-green insect i- • ilu-^eW £«tfwn the common ip Trci cs Ind enting regetation, and to the int of its triangular Bhape, quirk, active flighl n- lerable vaulting powers. It receives its peculiar popular name from similarity in shape to the male buffalo or bison. Thethon pronotum, is greatly \ i anteriorly, projecting laterally in t. BUt>ng horns, and is distinctly triangular, as shown in the illustration (''"■ '• "'• ^ is this peculiar shape rather than any knowledge of its habits that has given it its popular int, rest. During tl tenor : Moo I ome importa.it on other and Btrictly economic grounds. In tl ssippi VaJle] ally from the Mis- souri northward, well up into Canada, it has been the i verv grea1 Bin orchards, particularly to youn stock not, however, confining itself to fruit trees, but attacking also all of sii r '"' '"Jury is doe solely to the cutting up of the limhe by the female with her Bawlike ovipositor I fig. 1. /. <,) in the deposition of her eggs, in which particular the injury is not unlike that caused by the periodical cicada, and frequently is Bcarcely less in amoui account of the great numbers in which the insect occurs. On • L a badly infested orchard in the latter part of August, or in September, the buffalo tree-hopper will indicate its presence by flying away with a distinct buzzing noise from the trees approached and, as it is a very shy t, there is some difficulty in coming close enough to see it at work and observe its methods. Once well engaged in oviposition, however, it becomes for the time being fearless, and may be closely watched, even under a hand lens. When; the tree-hopper is abundant the smaller limbs of trees are often completely scarified overtheir upper and Lateral surfaces, so that the trees become dwarfed or bark-bound, make a sickly growth, and are rendered mOre liable to the attacks of wood-boring insects. This latter source of injury was first prominently brought to our notice in a communication from Mr. J. A. Pettigrew, superintendent of Lincoln Park, Chicago, who described the attacks of a borer in the smaller branches of the cotton- wood, Papula* mon ill fori, which caused the limbs to break off and fall to the ground in great numbers. Examination of the twigs submitted by him showed at once that they had been oviposited in very abun- dantly by the buffalo tree-hopper a year or two before, and that the old scars from the egg-punctures of this insect had furnished favorable con- ditions for the attacks of a wood-boring beetle, Oberea schaumii Lee. This beetle had deposited its eggs in the diseased spots left by the Ceresa, and the larvae of the beetle had burrowed up and down the twigs, weakening them and causing them to break off and fall as described. Healthy twigs would be distasteful or unsatisfactory to this insect, but the diseased condition, and particularly the dead spots left by the Ceresa, furnish the very conditions most favorable for this wood-borer, as simi- lar injuries do for many other wood-boring insects. HABITS AND LIFE HISTORY. . The habits and life-history of the buffalo tree-hopper are as follows : The adult insect chooses as a nidus for its eggs the twigs, preferably those of two or three years' growth, of various trees, particularly the apple, willow, cottonwood, maple, etc., confines itself in general to the upper surface of the twigs, and works more abundantly on the south side of the tree than on the north, although in this respect the prevail- ing winds and other conditions influence the insect. The eggs are deposited quite as readily in the new growth of old trees, as in young trees, but the damage is much more noticeable in the latter case. The eggs are placed in small compound groups of from 6 to 12 eggs each, arranged in two nearly parallel or slightly curved slits extending in the direction of the twig about three-sixteenths of an inch in length, and separated by one-eighth inch or less of bark (fig. 2, h) . In depositing the eggs the bark is cut by the ovipositor in such a way that the narrow bark intervening between the two incisions is cut entirely loose. This has a very important bearing on the subse- quent condition of the wounds made by the insect in oviposition. The object is doubtless to cause a deadening of the wood between the two rows of eggs, to prevent their being crushed and choked out by the sub- sequent rapid growth of the twig, and it is due to this peculiarity that the injury later assumes so serious a nature. A single incision made by the insect to contain its eggs would heal over and cause little after- damage, hut with the combination of two incisions and the killing of the intervening bark, causing it to adhere to the wood, a large scar is -«-■ ¥ produced, which, with ench subsequent year- growth, enlarges and ultimately assunx - an oval form, the dead bark ol the center breaking out. Aftei i i' hich have been thickly worked on \<\ the insect become verj Bcabby and rough, are easily broken off by the I, mid arc very liable i" attack by wood-boring insects (fig. '1. The adults first appear about the middle of July, and become n numerous during ml September. They begin oviposition about the middle ol or oven earlier, and continue this work until they arc killed by the frosts of early winter, sometimes working as late as lin- en. I of October. The number ol leposited by a Bingle female tin UK), and possibly 200. The eggs remain unchanged, or dor- mant, in the twigs until the following spring, hatching in May <>r early in June. The egg is about one-sixteenth of an inch long, Blightly curved, tapering toward the outer end and mine rounded at the inner one. It i< without markings, of a dirty whitish color, and cylindrical excepl as more or less angulated by the pres- sure of the wood and the adjacent • The eggs of the buffalo tree-hopper tuhject to the attacks of at least two minute egg parasites, which often do much to keep the insect in check. In general characteristics the larva' and nymphs resemble the adults, but are wingless and covered along the lly with numerous forked or barbed projections. POOD PLANTS. The larva 1 and pupa . as well as the adults, feed on all sorts of succulent ition, such as weed.- and garden vegetables, and are apparently not par- ticularly fond of the apple, much pre- ferring the more Bucculent annual plants. Mr. J. G. Jack reports that h< »•* ';' . , . , i. . j. , npi>le showing, a, tcmulc at work; /.. found the adult.- Feeding on the young •iinl ton.ler ,i1< nf thp nnnlp neirtlie witheggaln position. Blight): ana tena< r bdoois oi me appie, nt ar m* ground, hv which I suppose he means , , on oldei the watershoots, for certainly, after very careful and repeated observations in an orchard which wat infested as to he nearly ruined. I failed to find any indication of the feeding of larva or adults on apple. The injury, at any rate, in this direction, to fruit and shade trees i.- practically not worth considering. REMEDIES AND PREVENTIVES The destruction of the insects themselves is difficult and in genera] impracticable, because the larva- and adults feed on all sorts of vege- tation and are very widely distributed. The adults, also, arc too active and quick of fiighl to be successfully reached by caustic washes ; and spraying to destroy tie- early stages i- ordinarily out of the question, because it would necessitate extending the treatment to all surround- UNIVERSITY OF FLORIDA 3 1262 09216 4655 ing vegetation, and, as the adults are strong flyers, even this would give no absolute security. The limiting of the amount of foreign vegetation about and in orchards and nurseries is an excellent precaution, and little damage may be anticipated where the ground between the trees is kept clean and con- stantly cultivated. The larvae and pupa- under these conditions will be starved out. The orchard in which the writer first studied this insect, and which was so thoroughly infested as to be seriously injured, was one which had been neglected for a number of years and was full of weeds and succulent undergrowth, furnishing conditions under which an unusual multiplication of the Ceresa had taken place during a number of years. Surrounding and better kept orchards showed little, if any, damage. Vigorous pruning in the fall or winter should be given trees which have been cut up to any extent, and this with clean culture should reduce the insect to small numbers. It is possible that some good could be accomplished by planting trap plants between the rows ol trees, such as beans or other similar summer crops, which could be sprayed with the stronger mixtures of the kerosene and soap emulsion when the larvae became numerous, or about the first of July, but the more promising method is the cultural one already described. C. L. Marlatt, First Assistant Entomologist. Approved : James Wilson, Secretary of Agriculture. Washington, D. C, May 10, 1897. O