Historic, archived document Do not assume content reflects current scientific knowledge, policies, or practices. 4 A Ss Re, tes » ” % . a wo : aos See = ee : i) oy: Vey Jon 4 i , x, 7 ) a : a 7 r | P Fs yak 4 1 4 q ote Pe S i Cat @ s . :f . 6}. a y Fae « i ~ : — DEPARTMENT OF AGRICULTURE. DIVISION OF ENTOMOLOGY, BULLETIN No. 32. REPORTS || OBSERVATIONS AND EXPERIMENTS || THE PRACTICAL WORK OF THE DIVISION, MADE _ UNDER THE DIRECTION OF THE ENTOMOLOGIST. (PUBLISHED BY AUTHORITY OF THE SECRETARY OF AGRICULTURE ) ’ e by WASHINGTON: GOVERNMENT PRINTING OFFICE. 1894. ean. tk sae aT ay | iy. ry 34 | | | ifs ft it io ~ Ol in | ia ne ij ia | a 4 ; | ) Ar ) " N ew te ae - Roe: TESS oC RREN pe brea aa! - a, > L _s 1 rs a = z )EPARTMENT OF AGRICULTURE. DIVISION OF ENTOMOLOGY. Bubuetin No. 32. REEOR TES OBSERVATIONS AND EXPERIMENTS -. THE PRACTICAL WORK OF THE DIVISION, oe MADE UNDER THE DIRECTION OF THE ENTOMOLOGIST. (PUBLISHED BY AUTHORITY OF THE SECRETARY OF AGRICULTURE.) WASHINGTON: GOVERNMENT PRINTING OFFICE. 1894. a +a » ® . Pe a i ee ee ; - * - _ om - * ~ LETTER OF TRANSMITTAL. U. S. DEPARTMENT OF AGRICULTURE, DIVISION OF ENTOMOLOGY, Washington, D. C., April 14, 1894. Sir: I have the honor to transmit for publication Bulletin No. 52 of this Division. It comprises the reports of the field agents of the Divi- sion for the past year (1893), a summary of which has been included in my annual report. Respectfully, ©. V. RILEY, Entomologist. Hon. J. STERLING Morton, Secretary of Agriculture. ty) COMEERTS. er rine RAO MET PAR Sooo yon. 2 cree fe eis Sas bo Debe oe oo ees eee Ser eNDE INDI SCE = em eae tA ce eo a we Sook wee ee a REPORT ON INJURIOUS INSECTS IN NEBRASKA AND ADJOINING DISTRICTS oS Ee SA eS a ee ee ee ------ Lawrence Bruner.- REPORT ON SOME OF THE INJURIOUS INSECTS OF CALIFORNIA... D. W. Coquillett.. REPORT ON ENTOMOLOGICAL WORK IN OREGON AND CALIFORNIA; NOTES ON Piel ee CEE TATIONS .. = — 5 200.22. gee an sand Albert Koebele.. Mary E. Murtfeldt.. Se = ae eee baen Herbert Osborn-. 2b Bae eet A. S. Packard.. 5 J BERG Wo aw? REPORTS OF OBSERVATIONS AND EXPERIMENTS IN THE PRACTICAL WORK OF THE DIVISION. INTRODUCTION. For some years past it has been the custom, with the approval of the Secretary of Agriculture, to bring together in a single bulletin, at the close of each season, the formal reports of the field agents of the Divi- sion; thus, Bulletins 22, 25, 26, and 30 of the Division comprise the reports of the field agents forthe years 1889, 1890, 1891, and 1892. This present bulletin is a cortinuation of this series. Ali of the field agents represented in Bulletin ©0, with the exception of Mr. Larrabee, were continued through the year 1895. All, however, were discontinued February 15, 1894, and are no longer connected with the Division, with the exception of Mr. Coquillett, who has been called to Washington and is now an Office assistant. Mr. Bruner has reported in the main on the observations made upon injurious locusts, and judging from these observations there is no reason to fear serious injury during the year 1894. The occurrence in special abundance of several injurious insects, including the army worm and the wheat-head army worm is reported, and a number of new insect injuries are mentioned. Mr. Coquillett’s report consists principally of a somewhat detailed account of several different kinds ofleaf-eating caterpillars which attack fruit trees and nut trees in California. To this he adds a section on arseniureted and sulphureted hydrogen as insecticides. Mr. Koebele presents a few additional observations upon the sub- ject of the hop plant-louse in the northwest, and some additional facts regarding the latest importation of beneficial insects from Australia. Miss Murtfeldt gives a general summary of the injurious insects of Missouri for the year 1895. Prof. Osborn, in a like way, reports upon the injurious insects of Towa for the season, and includes some important observations on the hatching of the eggs of the horse bot-fly. Dr. Packard reports the almost complete recovery of the regions in Maine ravaged in 1878-’87 by the spruce worm, and he includes a number of new observations upon insects injurious to forest trees. C. V. R. 7 he Pel oe el Se, we ae LA ey w - o j REPORT ON INJURIOUS INSECTS IN NEBRASKA AND ADJOINING DISTRICTS. By LAWRENCE BRUNER, Special Field Agent. LETTER OF SUBMITTAL. LINCOLN, NEBR., November 3, 1892. Sir: I submit herewith a short report upon my investigations among the injurious insects of Nebraska and adjoining districts during the past summer. While these pests have not been generally numerous and destructive over the region assigned me, a few species from among the hosts of these creatures that are ever present have been sufficiently abundant to commit injury to the crops attacked and to require special attention on the part of the entomologist and agriculturist. Some of my time has also been given to a further study of destructive locusts and allied insects belonging to the order Orthoptera, in which I have been especially interested for some years. For this purpose three separate trips were made into quite distinct regions, viz, one to Colorado for the purpose of investigating a local locust outbreak about the town of Grand Junction, a second to western Nebraska and eastern Wyo- ming to examine into a reported appearance of the Rocky Mountain locust, and, lastly, a short tour of inspection through the eastern and central parts of Nebraska for the purpose of ascertaining exactly how numerous and extensive were the inju- ries caused by the ‘‘ native ” species of locusts that had been reported as committing hayoe with various garden truck, small trees, grape-vines, and also in some instances field crops. Many of the notes made on other insects than locusts, and in fact some of the lat- ter also, were obtained in connection with work carried on at the University of Nebraska or while engaged in field work for this institution. These latter are sub- mitted herewith as of some possible value to the general public aside from citizens of the State. Very respectfully, yours, LAWRENCE BRUNER. Ci V. RmEy; U. S. Entomologist. LOCUSTS OR **GRASSHOPPERS.” The past summer again has been noted as one in which the various species of indigenous locusts were present in overwhelming numbers over a large area of country. The injuries wrought by these insects were, therefore, great and widespread. Reports bearing on the subject were received from a number of correspondents located in this and adjoining States. The newspapers also contained like reports, from all of which it becomes quite evident that something definite in the 9 10 REPORTS OF OBSERVATIONS AND EXPERIMENTS. way of remedying the evil must be done soon if we would expect to escape future ravages from this source. Many of the common species, like the red-legged locust (Jelanoplus Jemur-rubrum), the two-striped locust (Melanoplus bivittatus), and the differential locust (Melanoplus differentialis), and others of like nature, are becoming more and more reconciled to ‘‘civilized ways” each succeeding year, and hence are bet- ter enabled to withstand these conditions than are others. This being true, they increase proportionately as the area embracing the conditions under consideration enlarges. Other influences, of course, also either favor or retard the increase of these particular species, us they do allied forms; but these influences seem to have less to do with the matter in their case than in that of the majority of species. They are the “hardy forms” of the family, and are capable of adapting themselves in their life struggle to a greater amount of variation in climate, altitude, and surface configuration. | Several trips were made during the summer in connection with the study of our destructive locusts. Besides the time thus spent, some attention was given the subject here at home. One of these: trips was made during the latter part of June to western Colorado, where I went to examine into locust injuries in and about Grand Junction. Although I reported at the time, I submit the following account of this trip for your inspection : A Report on Locust Injuries in the Vicinity of Grand Junction, Colo.— At the request of the Board of Trade of Grand Junction, I visited that place during the month of June to examine into a plague of locusts that were engaged in devastating the region about that city. After spend- ing a week here I found the conditions to be about as follows: About four years ago it was observed that grasshoppers were unusually abun- dant on a piece of waste land near the Grand River, a little south of the town of Fruita, which is situated about 12 miles west of Grand Junction. As the ’hoppers had plenty of food and were not destroyed by parasites or disturbed by the settlers or by birds to a sufficient extent to reduce their numbers, and having suitable places for the deposition of their eggs, the result is plain. The winter following the egg-laying reported was favorable, and the following spring, being likewise favor- able to the young, resulted in the spreading of the pest to several of the surrounding farms, where they did some damage to crops and orchards. Again nothing was done to diminish their numbers or to prevent their injuries or their spread to new ground. The season was also favorable to their development, egg-laying, and spreading. The opening of the third year came, and in course of time the young hatched and began their work upon the crops over a greatly extended area. Their injury was quite extensive, in fact, and comprised both field crops and orchards. This year many thousands of dollars’ worth of property was destroyed by them. The orchards in particular suffered from their depredations. As the principal product of the region is fruit, the destruction of fruit REPORTS OF OBSERVATIONS AND EXPERIMENTS. 11 trees was greatly felt by the settlers who happened to lose by their attacks. One orchard alone is reported to have suffered to the extent of $25,000. That this estimate was none too great I can attest from personally having visited and examined it. The orchard in question is of 80 acres in extent and composed of thrifty trees, all of bearing size. Fully one-half of the trees were destroyed by the locusts, which came by the millions from adjoining fields of alfalfa. They ate off the leaves and even stripped the smaller twigs of their bark. A great many other orchards were more or less completely destroyed by the pest last year. Even with all this amount of injury going on about them, the inhabitants did but little toward protecting themselves, and what little fighting they did do was undertaken so late in the year that it did comparatively little good even in the line of preventing egg depos- iting. The warfare did not begin until after the “hoppers had attained their wings and were spreading out over the region preparatory to egg- laying. Af this time they had mostly left the fields of alfalfa and grain and were nearly all in the trees composing the various orchards of the region. Here they remained upon the twigs and branches, feeding upon the leaves and tender bark of the new growth. In this situation it was next to impossible to dislodge them or get at them with a remedy. Some bran and arsenic was used by a few of the settlers in fighting the pest, but this was handled so carelessly in many instances that not only were domestic fowls and an occasional larger animal destroyed, but also nearly all of the native birds of the region that occasionally add to their insect diet other food were killed. In fact, the only good feature connected with the use of the bran-arsenic remedy in this par- ticular instance was the destruction of many rabbits. These latter were killed by the hundreds and pretty well exterminated in the imme- diate vicinity of the orchards where the remedy was used. The present year, the fourth in which these insects have been pres- ent in this region, I chanced to visit the locality about a week before the mass of hoppers had attained their growth. I was therefore in time to do some good for the residents by suggesting and showing them a more profitable and, at the same time, practical method of warfare suitable to the particular occasion, viz, the ‘‘ hopper-dozer,” or kerosene pan. It was ascertained that the majority of the insects were still confined to the edges of alfalfa and grain fields, or else were to be found amongst the rank vegetation growing along the edges of irrigating ditchesand over such grounds as were more or less frequently watered by the wastefrom these ditches. In such localitiesit wasseen thatthe most practical remedy that could be employed at this time was the * dozers.” Accordingly several of these machines were ordered made, and meet- ings of the farmers and fruit-growers and other interested parties called for the purpose of discussing the subject preparatory to attacking the foe. At these meetings, held in both Grand Junction and Fruita, addresses were delivered outlining the various methods that have been 12 REPORTS OF ‘OBSERVATIONS AND EXPERIMENTS. used at various times in the past in different countries and under divers conditions in fighting the locust pests of the world. In connection with the remarks made, charts were exhibited showing the differences among the species committing these injuries against which relief had been sought. Both the practical remedies, or such as can be applied with a saving, and the impractical remedies, or such as cost more to apply than would be the value of the crops intended to be saved, were described at some length. It is needless to say that I favored the practical rem- edies, although there were many among the audiences who insisted upon the adoption of some remedy where there would be little or no outlay of labor. Nevertheless the “practical” methods were insisted upon by me since the people were not overburdened with cash to such an extent that they could afford to go into a series of doubtful experiments at this late date of the trouble. Every circumstance seemed to favor the use of the hopper-dozers at this time.- Prior to my arrival the citizens of Grand Junction had secured a 10,000-gallon tank of crude petroleum for use in destroying the hoppers. This, as I afterwards ascertained, was intended to be used for pouring into the irrigating ditches and allowing it to spread over the country so as to come in contact (?) with the insects which it was intended to destroy. In my addresses I insisted that this would only be throwing the material away and would also destroy the vege- tation wherever the oil reached, and that the locust would be mostly left unharmed. We tried the oil in the ’hopper-dozers and were sur- prised atthe results. It worked much better,if possible, than the refined oil, and its cost was so very much less, being only 4 cents per gallon delivered at Grand Junction, that its use in this connection could be highly recommended. The comparative thickness made it more desira- ble because of its remaining in the pan to betteradvantage. It could even be cheapened by adding water to the oil in the pan on the dozers. There were several species of locusts concerned in the depredations in and about Grand Junction, as well as at other points in the surround- ing regions of Colorado. I found Melanoplus atlanis, M. bivittatus, and M, differentialis in the fieids of the region examined. There were also several other species very numerous in the valley and upon the surrounding hills wherever the vegetation was of sufficient size to sup- port them. One was an undescribed species of Pezotettix, as these insects have been classed by American writers, Somewhat resembling M., turnbulli Thos., only with very short and rounded tegmina. Like M. turnbulli, it seems to be confined chiefly to species of the Chenopo- diacez, of which the region contains many forms. It is especially fond of the greasewood (Sarcobates vermicularis). Peculiar enough was the fact that on my arrival much of the preparation for defense that was then under way was for the destruction of this Pezotettix, that did none or very little of the injury that had thus far occurred in the valley. I have proposed for this species the name Pezotettix cheno- REPORTS OF OBSERVATIONS AND EXPERIMENTS. 13 podii, and have furnished for publication in Insect Life a more detailed description than is here given. Whether or not my visit to the region in question resulted in any good to the settlers I can not say, for | have not heard from there up to the date of this writing. If the instructions which I gave and insisted upon being carried out were followed the valley could be practically freed from the pest. In estimating the cost for the extermination of the plague in this particular region, I believe that it could have been done with an expenditure not to exceed a couple of thousand dollars in money. Of course, the labor necessary for the extermination would be quite an item were it performed solely for the destruction of the “hoppers without any regard to the saving of crops, and if not done by the settlers them- selves upon their own and adjoining lands. Some of these figures were given to the public in my talks above alluded to. In closing my remarks coucerning this visit to Grand Junction, I wish simply to add that nature has made the region one of the very best fruit districts in the country. Climate is favorable, but few insect pests have been introduced from abroad, and these cannot live in the changed conditions of the arid climate belonging to the country. Few of the native insects can ever become injurious on account of the differ- ences in the food-plants that this change would entail. Lastly, the grasshopper plague of the past few years is due entirely to careless- ness on the part of the settlers themselves, and a repetition of such an occurrence can be prevented by a little watchfulness on their part. A - little care in the way of cleaning up about the waste lands lying along the ditches will be all that is necessary. West Nebraska and Wyoming Trip.—On the 25d of August I left Lincoln for the western part of this State and eastern Wyoming to examine into the reported locust injuries in that section of the country. Stops were made at Sidney, Pine Bluffs, Cheyenne, and the country lying at the headwaters of Pole and Crow creeks. Over this entire scope of country the various ‘‘ native species” of Acridians were exceed- ingly numerous—much more so than ordinarily—and any one who has collected these insects here knows what such an assertion means. Judging from the collections made at each of the localities visited, I have no hesitation in making the statement that fully one-half of the species common to the country embraced were injuriously numerous. Some of these had never before been observed by me to occur so plenti- fully. While but little farming is done in this region, the injury was nevertheless much felt by the settlers. The ranges were much reduced in value by these insects, which must have devoured fully one-half of all the grasses and other forage plants growing upon them. In many places the vegetation had been eaten so closely that a sheep would have had a hard time to feed upon the remnants. In settled districts and where irrigating is resorted to remedies can be suggested, but upon the high, dry plains of western Nebraska and 14 REPORTS OF OBSERVATIONS AND EXPERIMENTS. the adjoining portions of Colorado and Wyoming it is impossible to destroy these locusts by any artificial means known to me. Climatic _ conditions alone must be depended upon for remedying the evil, since the scope of country that would necessarily have to be covered is too great to think of stamping out the pest artificially. Rocky Mountain or Migratory Locust.—The Rocky Mountain or migratory locust (Melanoplus spretus) has not been reported from any point in excessive numbers during the past summer so far as I am at present aware. Stillit seems to have been sufficiently common over portions of the subpermanent region to warrant our watching its move- ments. On or about the 18th of August it was reported that grasshop- pers in considerable numbers were seen in the air at West Point, this State. Although it is not definitely known to just what species these hoppers belonged, they were without doubt stragglers of the present species, since at about the same time it occurred in moderate numbers here at Lincoln and several neighboring places. In fact, it has been noticed by me both in the air and on the ground several times during the summer, as it was also last summer. At no time, however, was it observed in sufficient numbers to do perceptible injury to crops or other vegetation, nor were the insects seen to deposit eggs. It did not appear among the species that caused the observed and reported dam- ages during the season. Injuries from * Native” Locusts.—Much injury was done during the summer by different species of our native locusts that have been very common at a number of localities in this and adjoining States. Here. at Lincoln we were obliged to fight them upon the experimental farm; and from a field of oats of about 50 acres in extent at least 50 bushels of winged locusts were captured with a hopper-dozer. They were hatched upon waste land adjoining the farm, and during the dry, hot weather of August left the weeds and moved into the more inviting fields. Numerous reports of similar injuries reached me from nearly every portion of this and adjoining States where farming was carried onextensively. The species concerned were the common ones usually engaged in such depredations in this central region, viz, the red-legged, the two-lined, the differential and the lesser migratory. In some local- ities all, in others only one or two, of these were concerned in the injuries. At different localities different ones were present in greatest force. As stated above it is quite evident that if the losses occasioned by these insects do not soon cease, something will have to be done to pre- vent their further depredations. OTHER INSECTS. The Army Worm.—This year has been noted in Nebraska as one in which the army worm (Leucania wnipuncta) was exceedingly abun- dant and did much injury to crops in many of the western, northwest- | } 1 | wk s REPORTS OF OBSERVATIONS AND EXPERIMENTS. 15 ern, and northern counties. Millet appeared to suffer most, although late oats and corn in a few instances were injured to some extent. One of these regions, viz, Ordai, in Valley County, was visited for the purpose of studying the insect in its work upon the crops. In this section of country several fields of millet had been almost entirely destroyed by the worms about a week prior to my visit. Irom the mil- let the worms moved into adjoining corn fields, at the edges of which they were fought in two or three instances by means of deep furrows in which logs were dragged backward and forward. Many of the lar- ve or caterpillars had already entered the ground and transformed to chrysalids; but still others remained in the fields hidden away under garbage of all kinds, or crept about on the ground. Nearly all of these contained the eggs of Tachina flies upon their heads and thoracic joints. Flying and walking about the infested fields were large flocks of Bartram’s sandpiper, red-winged blackbirds, sparrows, meadow- larks and several other birds that had been attracted by the rich food supply. These, together with the dipterous parasites, predaceous eround-beetles, and several wasps, had, I was informed at the time, destroyed more than three-fourths of the pests, thereby illustrating the value of these creatures in keeping injurious insects in check. Reports also reached me of the presence of this insect in hurtful numbers at the following localities: In Dixon, Holt, Jefferson, Custer, Valley, and several other counties not definitely stated. The Wheat-head Army- Worm.—This year for the firsttime I have seen the larva of Leucania albilinea to recognize it. Whilerunning the hop- per-dozer on the experimental farm in capturing destructive locusts, numerous specimens of the caterpillars of this insect were found mingled with the dead hoppers in the kerosene-oil pans. They were clinging to the stems of the grain and were knocked down by the machine as it was dragged through the field. Although quite plenti- ful, the larvie did not appear todo any appreciable injury in the field of oats that had been planted to cut for hay. No attempt was made to breed parasites from the insect, although some specimens were seen to contain eges of some dipteron upon the thoracicsegments and head. The Fall Web-worm.—This insect was again quite prominent among the insect enemies that were present in cities and towns during the Summer. Especially was this true with respect to its first brood. In the cities of Omaha and Lincoln it appeared in large numbers, partic. warly in the former city, where it stripped and covered the branches of most of the box-elders and some of the other shade trees with its unsightly webs. So alarmed about its continued presence and further injuries were many of the citizens that they cut down the trees * to save them.” In fact, the moths for the second brood issued in large numbers, laid their eggs and died. These eggs hatched, and the situa- tion certainly appeared quite critical. For some reason the greater proportion of the caterpillars of this second brood died or were destroyed 16 REPORTS OF OBSERVATIONS AND EXPERIMENTS. before they had become half grown. Whether their demise was due to disease or to the attacks of certain predaceous and parasitic insects, or both, I have not learned. That they disappeared at this particular stage of their growth remains a certainty, as I have been assured by several correspondents who were greatly interested in the subject and who watched them very closely. In this city also this second brood of caterpillars was less numerous than the first, and, as in Omaha, they dwindled from time to time so that comparatively few matured. The Hight-spotted Forester.—During July reports of injury by this insect to vineyards reached me. About the second week of the month a few of the grape-growers in the vicinity of Omaha became so alarmed about the ravages of the larve of this moth that they asked me to visit their vineyards at their expense. I did so and found that the cat- erpillars had been quite numerous and done much damage by devour- ing the foliage in several of the smaller vineyards. At the time of my visit (July 13) most of the caterpillars had disappeared; but such as remained were much infested with the eggs of some Tachina fly. As many as four to eight of theseeggs were frequently found upon a single caterpillar. These parasitic flies had evidently been quite abundant during the reign of the caterpillars. Some spraying with Paris green and London purple was done with beneficial results; but most growers ‘trusted in Providence,” and in this instance, at least, fared fully as well as did those who ‘“ fought.” The Stalk-borer.—While investigating the ravages of the eight- spotted forester about Omaha much injury caused by the common stalk-borer (Gortyna nitela) was also observed. The larve of this insect seemed exceedingly common, and were working on sweet-corn, tomatoes, egg-plant, etc., many of the stalks of which were bored into, causing them to die. In some instances two, occasionally even three, of the caterpillars were found working in a Single stalk. It is needless to state that considerable injury resulted from their attacks. As a remedy I suggested the collecting and burning of all injured stalks containing larvee. Unknown Lepidopterous Larva boring in Stalks of Corn.—Uate in August a specimen of the work of some lepidopterous larva boring in the stalks of corn was received from Mr. H. 8S. Smith, living uear Pen- der, this State, with the accompanying letter: ‘“T today send you by mail an insect that is working on the corn to a considerable extent, and that is at least new tome. It generally works about the second joint above ground. Have now mostly left the corn— not over one in twenty still in stalk.” In a second letter (September 5) he wrote: ‘“‘ Would say that the insects wanted have almost entirely left the corn. Only succeeded in finding two, which I send you. Found one that was being eaten by a white ~ maggot that looks like the larva of the common ‘bluebottle.’ There REPORTS OF OBSERVATIONS AND EXPERIMENTS. 17 are always two holes in the cornstalk, one at each end of where it has bored the inside out. The injured stalks break off in wind storms.” The insects had entered the chrysalis stage when received, so that the larva isunknown to me. It would appear from what Mr. Smith writes that some of the larve leave the stalks to transform, while others do not. At any rate, its comparative abundance and boring habits would indicate that we have in this insect a quite dangerous corn pest. It certainly will require additional study before we are entirely acquainted with it in all of its changes and life-history. The only encouragement that I can now offer is the presence, apparently, of a dipterous parasite in the “‘ white maggot,” mentioned by Mr. Smith. Swarms.of a Noctuid Moth.—Large swarms of Noctuid moths appeared almost simultaneously at many widely separated points in Nebraska and adjoining regions during apple-blooming time, and a number of letters were received concerning them. Many of my correspondents seemed to think they were the codling moth (Carpocapsa pomonelia) that had issued somewhat prematurely and were simply waiting for the proper time for oviposition. Consequently, their having taken alarm could not be wondered at. Judging from the material accompanying some of the letters, it is supposed that the swarms were chietly made up of a single species of cutworm moth (Chorizagrotis introferens), although several other species were represented in some loealities. The material received varied greatly in size and markings, as could be seen even from the much-rubbed specimens in question. At the time nothing was thought of the matter, and none of the insects were saved. A little later, when the Entomologist requested an investigation of the larval stages of this species, with its life-history and food-habits, the swarms of moths had disappeared, their going having been apparently as sud- den and complete a mystery as was their coming. * Ses OL ae REPORT ON ENTOMOLOGICAL WORK IN OREGON AND CALIFORNIA; NOTES ON AUSTRALIAN IMPORTA- TIONS. By ALBERT KOEBELE, Special Agent. LETTER OF SUBMITTAL. ALAMEDA, CAL., November 8, 1893. Sir: I herewith submit to you my report of observations during the year. Special reports on work done in Oregon and Washington upon Phorodon humuli Schrank., and on the investigation of the condition of predaceous insects sent from Australia dur- ing my last trip to that country, have been made and forwarded to you. Ishall here mention only certain additional facts connected with the same and note some other observations made. Respectfully, yours, ALBERT KOEBELE. ©, Vs RILEy, 2. U. S. Entomologist. The hop louse, as could plainly be noticed during spring, has not been so numerous during the present season in Oregon and Washington, owing to the increase of insects living upon it, as shown by the interesting letter of September 16, 1893, from Mr. H. J. Miller, of Aurora, Oregon, as follows: * * * The hop crop is very light, owing to cold rains in the spring and then continual dry weather. In the spring when the lice emigrated to the hop the weather was cold and rainy, and I noticed that the lice on the vines would turn white and sickly and finally die. No spraying was done, as it was not necessary in this vicin- ity. A few lice survived the cold weather, and just before picking time the weather turned sultry, cloudy, and rainy, favorable for development of lice, and it could be noticed that they increased very fast; but picking time was too close at hand for them to do any damage. As to collecting the lice from the plum trees, I have great faith in it, but to make it successful, farmers for miles around should closely inspect their trees and free them from vermin. One hop yard seemed to be infested as much as any of those of our neighbors, but as some of our nearest neighbors had plum trees and did not clean them, I am sure some of the lice emigrated from their trees to our yard, for they must be able to travel long distances. The ladybirds increased for a while in the spring, but as the summer advanced they began to dwindle away, and at picking time were getting scarce. * * * 1493— Bull. 32——3 33 34 REPURTS OF OBSERVATIONS AND EXPERIMENTS. A fungous disease appears to have destroyed large numbers during the early summer. It was only at picking time that the lice became numerous, aud in consequence the coming season may again show an increase. As already mentioned, the importance of an early warfare against the hop louse can not be overestimated. Spraying and hand- picking should be practiced upon all the plum and prune trees during the autumn and early spring. Since the season has been so backward it is not possible for me to give a list of the most efficient enemies of the hop louse, viz, the Syrphid flies, and but few of these were observed during my work. Coccinellide, however, could be seen by the thousands during early spring. I givea list of those met with in the yards, with notes thereon. Notes on Ladybirds found in Hop Yards.—The largest number were of the genus Hippodamia, and it is a difficult matter even for an expert to define the species when seeing largé numbers together. Hippodamia convergens Guer. and H. ambigua Lec. were the most numerous in the hop yards during the early spring and were preying upon various Aphidids infesting weeds. After devouring all these, they, as well as all other species, left in all directions and could be found almost any- where where plant-lice existed. As observed, these insects will also prey upon Lecanium in its young stages after the most of the Aphidids have disappeared. H. 13-punctata has been but rarely met with. JH. spuria Lec. and H. parenthesis Say were more numerous and always upon plant-lice. Coccinella annectans Crotch is a rare insect that feeds upon Aphidids as well as upon the young of Lecanium. Coccinella trifasciata Linn. is an abundant ladybird that is found feeding any- where upon plant-lice, and as these become rare with the advance of the season, it readily feeds upon bark-lice. C. transversoguttata Fab. is one of the largest of this group and was also found in numbers in the hop yards as long as the plant-lice upon which it preys existed. The first eggs of any found amongst hop vines belonged to this species. This was before the yards were plowed, which will destroy nearly, if not all, the early stages of these valuable insects. Cycloneda sanguinea Linn. is a very common ladybird and one of the most active in hunting up the solitary Aphidids. Many colonies of the hop louse under observation on plum and prune trees were entirely cleaned out by this beetle and often in a single day. In order to get at the proper results of the experiments it often becomes necessary to cover the lice treated with netting on account of this insect. Adalia bipunctata Linn. is only occasionally found. I have bred the same from larve feeding upon an Aphidid infesting Crategus at Sisson, Cal. It has also been found near Alameda, upon orange trees infested with Lecanium. A. humeralis Say was found feeding upon plant-lice in Oregon and in California. I found it more often upon plants infested with black scale. A very common and variable ladybird is Harmonia picta Rand., which is met with occasionally feeding upon plant-lice. The “ i kK i ae «Fs " ¢