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found it on the same food plant in Ohio. The grape scale, Aspidiotus uræ, is very often found in Illinois, but is not a serious pest so far as I know.

The oyster shell bark-louse (Mytilaspis pomorum) is common through. out Illinois, and is, in my opinion, the cause of far greater injury to apple trees in that State than has been attributed to it. I believe it is double-brooded as far north as Springfield, Ill. The eggs of the first brood hatch early in May at Champaign, and I believe a second brood appears in August. I found this scale on rose (Baitimore belle) at Relay Station, Maryland, this season, from which I bred the adult male insects August 8.

The scurfy bark-louse (Chionaspis furfurus) is also very injurious to apples in Illinois. I have shown by a series of experiments, conducted a year ago, that this species is two-brooded. At Champaign the young of the first brood appear about the 1st of May, and the female begins to deposit eggs for the second brood usually the first week in July. The young of this brood begin to appear about July 10, and the adult males are abundant usually from the 10th to the middle of August.

I have found several other species of Chionaspis on shade trees in Illinois, but will mention only three of them in this place. The willow scale (Chionaspis salicis) is very common on willow. The pine scale (Chionaspis pinifolia) is also very destructive. Several large and beautiful pines on the campus of the University of Illinois have been killed this

season, and two were dug up and burned last year. The scale is double brooded in that region, the first brood appearing usually the first week in May and the second the first week in July. Another spe. cies of this genus, which I bave described as Chionaspis americana, is found on white elm (Ulmus americana) throughout Illinois. Mr. R. H. Pettit has also sent me the same species on elm from Minnesota. It is very destructive to elms planted for shade and ornamental purposes. I have also found it upon virgin timber, and believe that it is a native American insect. The female scale is yellowish brown at first, but becomes lighter, nearly white, with age and exposure. The male scale is pure white, and characteristic of the genus. The eggs are purplish. There are two broods, the first appearing about the 1st of May and the second early in July. The male is peculiar in that there are two forms-one with well-developed wings and the other with mere stubs. The attack is confined to the trunk, branches, and twigs. The male scales often cluster on the underside of the leaves; an occasional one, however, may be found on the upper surface.

The rose scale (Diaspis rosa) has been very destructive to raspberry and blackberry in Illinois for several years.

It is also common on rose. The peach lecanium (Lecanium persica) was reported to me by the Prairie Farmer from one locality in Madison County, Ni. The attack was confined to a single tree, which was cleared by close pruning and a thorough washing with soap. I bred an adult male of this species from material from this tree April 24, 1895.

Last season I found a Lecanium very abundant on white elm in Illinois, and worked out its life history through the first brood this spring. I have not determined it specifically.

NOTES ON THE ENTOMOLOGICAL EVENTS OF 1896 IN IOWA.

By HERBERT OSBORN, Ames, Iowa. It is not my intention in this brief note to attempt a review of the insect peculiarities of the season, but merely to call attention to some of the striking events of the season up to the present time.

The army worm (Leucania unipuncta) has perhaps occasioned more general attention and apprehension than any other species, and there has undoubtedly been no small amount of actual damage as a result of its abundance.

It was first reported in May from the southeastern part of the State, and from the fact that it was four or five weeks earlier than the time of its usual occurrence in the State I was inclined to believe that one of the common species of cutworms was responsible for the reports, especially as such cutworms had been received from other localities.

The receipt of undoubted army worms, however, set all question at rest, and within a few days specimens and reports from many localities proved a general invasion. The numbers were certainly greater than have come under my observation before, and can only have been equaled by an outbreak some thirty years ago, which, according to reports of early settlers, was quite destructive, but which from the fact that only a small part of the State was settled was of more restricted injury.

A second brood appeared in July and, like the first, caused quite general apprehension, especially where oat fields were destroyed and corn threatened.

With this brood, however, there was a very general appearance of parasites, especially of Microgaster militaris, and so extensive have been the operations of the latter that I do not anticipate further serious destruction.

The chinch bug bas demanded attention through a considerable area, embracing particularly several southeastern counties that have been similarly atiected during ihe two preceding seasons. Injuries, however, have been less, I surmise, than last year. The season has been much more favorable to the spread of disease among them, and either from a natural spread or as a result of artificial introductions lias been, so far as reports will justify a judgment, much more effective. While showing the possibilities of this method under favorable conditions it only emphasizes the necessity of such conditions and strengthens my belief that it would be unwise to encourage farmers to rely upon this means as their sole dependence in control of the chinch bug pest. We have this season been sending infection material with instructions to

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scatter at once in the field where bugs are most abundant, using the infection box only in case of extreme dryness or where additional material is desired.

A quite unusual attack has occurred upon potatoes by a species of leaf hopper which, so far as I am aware, has never been destructive to this crop in this locality. It first appeared upon early potatoes the fore part of July and in many fields caused an almost total loss of the crop. Late potatoes suffered less either because of the changed conditions of weather or the movement of the insect to some other crop. The insect agrees in every particular with the Empoa albipicta as described by Forbes, but I believe this species is really an Empoasca and to be referred to the mali of Le Baron. That it may live quite as freely on potato as other plants is shown by the fact that larvæ developed there. An experiment with kerosene emulsion showed that by using four nozzles and a strip of board to drag the tops of the vines, so as to expose the under surface of the leaves and also to cause the insect to fly into the air, a large proportion could be destroyed. In this way it is believed we greatly benefited the field experimented upon.

Scale insects have naturally received considerable notice on account of the apprehension that the San Jose scale may at any time appear within our borders. Thus far there has been no appearance of this pest in the State, though I have on many occasions examined specimens that were supposed to be of this species. The most interesting of the species that has come under my notice in this connection is the Aspidiotus rosa, which caused quite serious destruction to roses and some other garden plants in Muscatine. The species has not been observed in the State hitherto, but seems to have become quite a serious pest in that locality.

The hickory bark-beetle (Scolytus 4-spinosus) has caused considerable damage in some localities and attracted attention particularly by the destruction of foliage, due to the cutting of the adults into the petioles of the leaves.

While this injury attracts much more immediate attention than the work of the larvæ in the bark, there can be no question but that where it occurs there is a certainty of the further injury which the larvæ will occasion by their operations.

The Hessian fly (Cecidomyia destructor) has made its appearance in the State, and so far as I am aware this is the first season that it has been recognized or in which it has occasioned noticeable losses. If it has been present hitherto has been in such limiterl numbers as not to attract attention, or at least not to be reported to the station. Its principal center of injury at present appears to be in Buena Vista County, wbich is in the northwest part of the State and one of the spring-wheat counties.

A point which is of interest as well as of particular significance to the wheat growers is that its parasites seem to have occurred with it in full force, as among the specimens sent me all have produced the Semiotellus destructor instead of imago Cecidomyia. Usually it is believed that the parasites are somewhat behind the host in occupying any new territory, but here they seem to have followed with them in their first introduction or to have so nearly kept pace with them as to warrant the hope that they may prevent any great devastation.

The elm span-worm (Eugonia subsignaria) was unusually destructive in one of the southeastern counties (Washington), a correspondent in that locality reporting that the larvæ had defoliated “acres and acres” of timber land. This is, I think, the first serious invasion of this insect ever reported in the State.

The cucumber aphis, the potato stalk-weevil, the squash borer, and some other species have been locally destructive, but on the whole probably not more serious than usual. In many different species there has been a sufficient variation froin normal abundance to show the influence of peculiar climatic conditions.

IS COOPERATION FOR THE CONTROL OF SAN JOSE SCALE

PRACTICABLE?

By WM. B. ALWOOD, Blacksburg, Va. When I undertook to collect data on this subject I fully expected to be present at the meeting and present my matter in person. Circumstances have, however, prevented my attending, and I will only offer a few notes covering in part the subject I had intended to discuss. I hope, however, that what is said will lead to discussion and action by the members of our association.

Messrs. Howard and Marlatt have so thoroughly treated the general subject of the San Jose scale that it is unnecessary for me to say any. thing whatever covering the details of the life history and like critical data concerning this insect.

Early in the present year I began collecting data relating specifically to several practical points, viz: (1) The spread of this insect in the several Eastern States infested; (2) the thoroughness and manner of inspection; (3) the extent to which nurseries are infested and the probable facts as to whether this insect will become a permanent habitant and continue its destructive work throughout the extent of the Atlantic States. Also the question of legal enactments for the control or eradi. cation of this insect and the extent to which cooperation seems advisable was made a part of the inquiry.

Such information as I have obtained has come largely from the station entomologists and other public officials in the colleges or the various State boards of agriculture.

After making as thorough an inquiry as I could well do through the persons who ought to be informed on this matter, I find that, unfortunately, there are not sufficient data for determining with any accuracy

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the spread of this insect in the several States infested. In only one instance, and that the small State of Delaware, did I find that there has been a systematic inspection of the State, and New Jersey has doubtless been much better inspected than any of the States of considerable size in the East. So it would appear that our present knowledge of the infested areas in the several States has come largely though reports of its injurious occurrence either in nurseries or orchards and not from critical inspection. This suggests, in the first place, that we are even yet, after all the literature that has appeared upon this subject, quite in the dark as to the probable damage which agriculture may suffer in the near future from this pest. We, in fact, are not yet in position to speak at all of its probable or possible occur. rence in a large number of isolated places over the Eastern States where it has not yet been reported as injurious.

To illustrate how easily a whole neighborhood may be infested with out baving come to the knowledge of entomologists, I may cite a few instances which have come under my observation. One of these was in the lower valley of Virginia, near Winchester, one of the best cultivated and most prosperous sections of the State, where a considerable orehard had become infested and some of the trees were already dead, yet this infection was not known and had not been reported at all until by mere chance a party interested observed the infested trees and sent specimens to me for determination. Another instance which well illustrates this point is that of the Salem district in the upper valley of Virginia. This place is less than 40 miles from the Virginia Agricultural and Mechanical College and the center of a very intelligent community, surrounded by highly cultivated farms and agriculturally one of our most prosperous sections, yet the scale had existed there for four or five years and been disseminated quite generally over the immediate locality by the tree dealers. During all this time the fact of this infection was totally unknown, though I had constantly received from this place numerous specimens of other injurious insects and fungi affecting fruit plants; and to enforce this point more strougly I will relate an incident connected with the occurrence of this scale at Salem, Va. A few days prior to my official inspection there certain parties, observing that many fruit trees were infested with scale insects, sent specimens to Congressman P.J. Otey of that district, and he submitted them to Mr. Howard, who in due course pronounced them to be a spidiotus aneylus. Yet my inspection revealed the presence of the pernicious scale in great abundance. In fact it was by far the most common injurious species in the community, yet by a strange chance a common native species was sent to Washington, and these people were congratulating themselves on being free from San Jose scale.

Less than two days' work in this community revealed to me the presence of the San Jose scale in very serious numbers at ten different points in and about Salem, and I doubt not that double and treble this number of premises are actually infested.

5850—No. 6—6

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