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mixture are used by a single farmer. The process is expensive, of course, but the results are good, and without it the orchards would be valueless. It is claimed that especially on peach the lime, sulphur, and salt mixture acts as a fungicide, and prevents leaf curl, while apparently strengthening the tree and enabling it to better retain the set of fruit. In the immediate vicinity of San Francisco and south of that point, natural causes have resulted in keeping the pernicious scale in check. In the first place the scale has the appearance of becoming worn out; that is to say, there are a great many dead specimens to be found on the trees—the young themselves, when moving about, appear as if they were only half alive-and altogether it seems as if there was some force at work that is weakening the insect. It is also preyed upon by Chilo. corus bivulnerus in all its stages, and infested by Aphelinus fuscipennis, both of which are also found in the Eastern States. These two insects breed through almost the entire year. The Aphelinus probably continues throughout the entire season, while the Chilocorus has probably only a very short resting period in midwinter and another perhaps somewhat longer in midsummer. The scale has quite a long period of rest, and does not begin breeding in spring until May. The result is that the predaceous and parasitic enemies have a distinct advantage over the scale and are able to keep it down to harmless numbers. None of the insects introduced from Australia which have been credited with controlling the scale ever had any effect upon it whatever. With the possible exception of Rhizobius lophantæ none of them were introduced into California until the scale in the southern part of the State had spent its force, and furthermore, lophanta, the only species which has been found feeding upon the insects at all, does not become numerous until well along in the summer, and has besides no great partiality for orchards. It is found as frequently in the canyons as it is on cultivated lands. As to the predaceous insects introduced from Australia, their importance in ('alifornia has been grossly exaggerated. Up to the present time they have not established themselves permanently in more than two counties in the State, and in regions where thousands and tens of thousands have been introduced they have died out almost completely. Very little of the evidence that is given as to the work done by these insects is reliable. Whenever any decrease of black scale is observed, and there is any Rhizobius rentralis about, this insect is credited with the work done. In a number of instances where trees were said to have been cleared by this insect, or rather the scale destroyed, it was found that while the scales were dead there was no sign of an injury such as would have been made by feeding upon it by either the larva or adult of Rhizobius ventralis. No reliable observations have been made, and a very large proportion of what is asserted is guesswork. Rhizobius debilis, about which so much has been published, and for which so much has been claimed, was not found in California at all, and there is every reason to believe that the insect bas died out entirely. In most cases the common Californian Scymnus marginicollis is mistaken for Rhizobius debilis and sometimes for lophantæ as well. Rhizobius debilis does not occur in any of the collections in California, except in imported specimens.
Rhizobius lophante was probably in ('alifornia before it was sent in by Koebele, and must have been accidentally introduced quite a number of years ago. It was already among the mountams some miles north of Pomona in 1891, and was taken in some numbers in San Diego in 1892. It is an insect that is at least as abundant in the woods and on the shrubbery of the mountains as it is in cultivated orchards, and though specimens of it seem to be found almost everywhere, yet they never occur in any such numbers as to make the species a factor in keeping down scale insects. Aside from the l'edalia and Norius, which feed upon the Cottony Cushion scale, the species mentioned are the only ones that have been in any way established in the State. Perhaps Orcus chalybeus should be referred to here, because that is still to be found in small numbers in one orchard not far from Los Angeles. It has not increased, however, since the first year or two, and, on the contrary, seems rather to be dying out just as 0.australasia did two years previously. Taking everything into consideration, there is nothing that warrants the assertions put forth by the horticulturists of Califorma. There is no doubt that the native parasites of scale insects are very efficient in keeping down the insects to some extent; but of the 60 species imported by Koebele, in many thousands of specimens there is not one that can be considered a success at the present time. Of course there is a belief to the contrary, and some superficial evidence to sus'tain it; but there is at least as much evidence in the opposite direction, and it seems to me that the state of affairs hardly warrants the discontinuance of destructive measures against the injurious insects.
Mr. Howard said that the paper just read by Mr. Smith was one of the most important of the session, and that he was interested to know that Mr. Smith's observations corroborated Mr. Riley in his prophecy as to the futility of these later and miscellaneous importations. Even if Mr. Koebele has proved to be a poor prophet, however, no one will deny that he is an excellent collector and good observer, and at the time of his very favorable report of the condition of these importations, made at Mr. Riley's request (see Insect Lite), the ontlook was inuch more flattering than it now is, the situation having evidently in the mean time altered very materially. With reference to the explanation offered by Mr. Smith for the failure of these importations to become well established, viz, the unsuitability of the climate, he suspected that there might be another partial explanation in that Mr. Koebele lad undoubtedly introduced an important parasite of the ladybirds (a species of Homalotylus), entirely inadvertently, and that the matter had been apparently lost sight of, and he asked Mr. Smith if he had learned anything of this interesting phase of the matter.
Mr. Smith replied that he had heard nothing of this ladybird parasite. He stated also that Rh. ventralis is not easily established and dies out very readily, and is also preyed upon by Chrysopas. He thought Mr. Koebele in his report of conditions in 1893 had not given sufficient credit to the native twice-stabbed ladybird, everywhere present in abundance.
Mr. Howard, referring to the shipment of supposed introduced Australian ladybirds from California to Washington by Mr. Snow, collected and transmitted at the request of Mr. Smith, described the character of the material transmitted, which contained no Australian species whatever, but were all American species, no less than three of them being plant-feeders. After surveying the whole field, however, we can not but admit that one at least of Mr. Koebele's later importations has been of great benefit. That species is Cryptolamus montrouzieri, which was imported into Hawaii for the purpose of ridding the coffee plantations of Pulrinaria psidii. The latest communications which he had received from Hawaii, both from the commissioner of agriculture and lands and from Mr. W. G. Wait, of Kailua, indicate that the expected work has been thoroughly accomplished. Through the kindness of Mr. Craw, specimens of this beneficial ladybird in the larval state have been received at the Department of Agriculture and have been placed npon orange trees affected by mealy bugs. The ladybird larva bave taken hold energetically and are now in flourishing condition, while the mealy bugs are fast disappearing.
Mr. Smith gave an iustance of the etliciency of this Cryptolemus against mealy bugs, and stated that it is not adapted to out-of-door life in this country, but will accomplish good work in greenhouses.
In reply to a question from Mr. Fletcher, Mr. Smith said that he had not observed rentralis feeding on fungus, but he was firmly of the belief that it has this habit.
Mr. Hopkins presented a paper entitled "Insect Enemies of Forest Trees.” The paper has been published in the Canadian Entomologist, Vol. XXVIII, No. 10, pp. 243-250, October, 1896, and in accordance with the policy adopted by the association can not be reprinted in its published proceedings.
In discussion Mr. Fletcher said that the subject covered by Mr. Hopkins is of great importance to ('anada on account of the large lumbering interests there. He stated that the experience which Mr. Hopkins hail described following forest fires is a cominon one in Canada. The two splecies most injurious in Canada under these conditions are Monohammus scutellatus Say and M.confusor Kirby. He gave an account of the habits of these species, mentioning, among other interesting points, the fact that they often go into the hard wood the first year, and that the larval
life, contrary to the old belief, is comparatively short, not exceeding one or two years, the very long periods sometimes recorded being undoubtedly accidental or abnormal. He said that in some of the
. forests north of the Ottawa River there are scarcely any trees that are not injured, and the yearly loss in Canada amounts to upward of a million dollars. He described the remedial treatment practiced in the Dominion, and particularly what is known as “rossing” of trees, which consists in cutting a strip of bark along the full length of the upper side of the log, causing the remaining bark to dry and eventually drop away. If they are protected by being immersed in water, it is necessary to turn them over in summer, otherwise the insects will work in the exposed side. After forests have been burned over, it is necessary to cut very promptly on account of the rapidity of the development and work of the beetles in question. He referred to the current belief among woodmen in explanation of the sudden appearance of these borers in burned timber to the effect that they develop from the souring of the sap.
Mr. Hopkins stated that this is also a common belief in West Virginia.
Mr. Fletcher further referred to the practical difficulties in getting wood cut at different seasons of the year. For instance, in early summer it is impossible to get cutters to go into the forests on account of the plague of mosquitoes aud black flies at that season.
At the request of several members Mr. Fernald gave a résumé of the present status of the work of the gypsy moth committee, and his remarks were supplemented by Messrs. Forbush and Kirkland.
Mr. Fernald referred to the action of the association at its Springfield (1895) meeting, and stated that at the legislative bearings of the past spring, held with reference to determining the size of the appropriation to be granted for continuing the work of exterminating the gypsy moth, no representations made by the gypsy moth committee, the director, or himself carried a fraction of the weight that the indorsement of the association afforded. The legislators recognized the association as a body of eminent scientists and valued accordingly the opinion of its members.
In speaking of the present condition of affairs brought about by the failure of the legislature to provide sufficient funds for the continuance of the work in the most approved manner he stated that future action must be along one of three lines:
(1) To continue the work with a view to extermination. This can be done, but will involve a vast ontlay.
(2) To attempt the control of the insect, but with no idea of the ultimate extermination. This means a great annual expenditure that must be continued indefinitely.
(3) To abandon the whole work, “let the insect spread at its own sweet will," and trust to the property owners to care for their own estates. Should this latter course be adopted, it would be impossible to say how long a period of time would elapse before the pest would spread over the whole of New England and into adjacent territory. The insect woull soon be in a condition to spread fast through avenues of traffic, and its dittuision over the whole country would probabiy be a matter of comparatively short time.
The committee in charge and those directly connected with the work have been criticised because the importation of parasites has not been attempted. This, he explained, had not seemed wise while the work has been carried on with a view to extermination, since the latter condition involved the destruction of all large colonies wherever they occurred and would thus prevent the successful breeding of parasites. Such insects would require the most favorable conditions in order to become acclimatized, and this would necessitate the preservation of large colonies of the gypsy moth as food for the parasites. Should the work of extermination be abandoned, a careful study of the natural enemies of the gypsy moth in its native home would be advised. At the request of Mr. Fernaldi, Director E. H. Forbush presented a statement of the condition of the gypsy-moth work as it now exists.
Mr. Forbush first called attention to a common mistake in considering the work as that of the “gypsy moth commission,” it being instead in charge of a special committee of the State board of agriculture. There was at the inception of the work a “commission” proper. This was removed by Governor Russell for malfeasance in office and a second commission appointed. This body served but a short time, the work being subsequently delegated to the State board of agriculture. To render the present status of the work more intelligible, Mr. Forbushi gave a brief résumé of the history of the effort to exterminate the insect.
The work began under a grave misconception of the amount of territory infested. As soon as the State board assumed the direction of the undertaking it was found that the infested territory extended, not as believed by the first commission over a small and well-defined area, but instead over some thirty cities and towns. The size of the infested territory as considered by the first commission compared with the actual area later found to be infested was very aptly illustrated by a comparison of the size of a dollar with that of a broad-brimmed hat. In the fall of the second year of the work conducted by the State board Mr. Forbush and Mr. Fernald made a careful inspection of the infested region and prepared an estimate of the cost of extermination. Upon the convening of the legislature they asked for all the money that could be economically expended in one year, and no more. At that time the legislature lost the golden opportunity. Had suflicient funds been forthcoming to enable a vigorous prosecution of the work under the favorable conditions then existing the present condition as regards extermination would be much more satisfactory. But this was not all. The same legislative policy of reduced appropriations, granted after long and costly delays, has been followed year after year.
The work has suffered from two causes—apathy of friends and opposition of enemies. Friends of the work were apathetic except where their own property was damaged by the insect. Others opposed the work from personal reasons.
Mr. Smith inquired whether or not the infested territory had been reduced.