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found under the bark of chestnut, maple, and hickory, fed freely in confinement on pieces of the bark, one example living from May 24 to July 2.
The writer has not been able to ascertain the larval habits of these last two species, but it may be surmised that they live under or in the bark somewhat after the manner of C. parochus in butternut.
Plocamus hispidulus Lec.—Beaten from limbs, and probably lives on this tree, as it has been found by Mr. Schwarz breeding in the "outer layers of nearly dead wood” of locust.
Dryocoetes granicollis Lec.-Two colonies observed at base of trees near roots; insect in all stages, mostly pupa and immature imagos.
Other species of Cerambycidæ, found at Wedderburn and elsewhere on chestnut, have been reported upon by the writer in the Proceedings of the Entomological Society of Washington (Vol. III, pp. 95–102), and need not be again mentioned at any length. The list includes: Callidium æreum Newm.; Xylotrechus colonus Fab., and its parasite, Xylonomus rileyi; Neoclytus erythrocephalus Fab., and its parasite, Bracon eurygaster; Cyrtophorus verrucosus Ol.; Euderces picipes Fab.; Leptostylus macula and collaris; Liopus variegatus, and its parasite, Ephialtes irritator, and predaceous enemy, Tenebroides corticalis; and Eupogonius vestitus Say.
DAMAGE TO PINES.
A year or two before the reports of insect damage to chestnut trees, came complaints of injuries to coniferous trees in Virginia, West Virginia, and District of Columbia. The first of these was from Mr. M. H. Farley, of Strom, Botetourt County, Va., who wrote October 26, 1891, of the “frightful devastation” in the pine timber of that State. The scrub pine (Pinus inops) was attacked first, and it was thought that unless the insect was checked it would “soon sweep the pine timber from the State.” The insect, which proved to be Dendroctonus frontalis, was apparently working southward, having at that time reached the North Carolina line. It was also reported present in white pine (P. strobus).
During September, 1892, Messrs. J. R. Beaty & Co., of Crow, W. Va., reported that the same insect was apparently the cause of the destruction of pines in Raleigh County of that State, as well as in Virginia.
Other reports of damage reached the Department during the next few months, one of which, emanating from Port Republic, Va., was the occasion of a visit by Mr. E. A. Schwarz of this Division, but did not result in the finding of a single living specimen of Dendroctonus at that place, although thousands of dead beetles were in evidence of their previous abundance and injuriousness. This was in August, 1893.
One result of this trip was the discovery of a fungoid disease which manifested its presence upon the dead bodies of the beetles under the bark. Mr. Schwarz is of the opinion that this disease was responsible for the sudden disappearance of the beetles.
Mr. S. J. Wood, of Washington, Rappahannock County, Va., stated that the dying of pine and spruce timber in that and surrounding counties was very extensive a few years since, and quite generally recognized throughout the pine forest land of the State.
Mr. Samuel K. Behrend, an employee of the Navy Department, spent considerable time in travel through the Southern States of this region while the infestation was at its height, and noticed the dying off of millions of pine trees in Virginia, injury being particularly noticeable in Buckingham County. The same conditions prevailed in North Carolina.
The primary cause of the mortality among the pine trees is enshrouded in as much mystery as in the case of the chestnuts. Whether due primarily to insects or not, certain it is that the so-called "destructive pine bark-beetle" (Dendroctonus frontalis) did great damage to the pine and spruce forests of this part of the South. A great many dead pine trees in
FIG. 43.- Dendroctonus
frontalis : a, dorsal view this vicinity were stripped of their of beetle; b, lateral view—enlarged about 6 bark, and the galleries of this spe
times: c, antenna-greatly enlarged (origi.
nal). cies, together with the dead beetles, were found in all. A noticeable feature of the insect work on pine was the almost entire absence of the galleries of other common scolytids, such as Tomicus cælatus. In one spruce, however, T. cacographus was as abundant and apparently as injurious as Dendroctonus.
It will be unnecessary to dwell at length upon the subject of the devastation of pine and spruce forests, since, as previously stated, injuries were reported too late for investigation, and the principal ascertained facts in the matter have already been given to the public by Mr. Hopkins in the columns of Insect Life and elsewhere.
The accompanying illustration of this species (fig. 43) will enable its recognition. It resembles the species of its genus in color, ranging from reddish to dark brown, but it may be readily distinguished from the other species by its much smaller size, which is one-eighth of an inch or slightly longer. An enlarged antenna (c), which is of a form characteristic of frontalis, will further facilitate its identification.
The following is the credited distribution of the species: “ Carolina" (Zimmermann); “Lake Superior to Georgia” (Le Conte); “California, Arizona, Maryland” (Dietz). To this must be added the District of Columbia, Virginia, and West Virginia.
Since the above was in type Mr. Hopkins has informed the writer that he now has in MSS. a full report on this topic which will soon be given to the public.
OTHER BORERS AFFECTING CONIFERS.
Owing to the absence of Dendroctonus frontalis at the time its investi. gation was attempted, little time was devoted to the boring species affecting coniferous trees. The following, however, are worthy of mention:
Leptostylus commixtus Hald.-Under this name a cerambycid has been included in Fitch's list of pine insects of New York State, on the strength of the occurrence of the beetle on pine leaves. What the writer takes to be the same species was reared at this Department from pieces of Pinus inops taken at Wedderburn, Va.
Graphisurus pusillus Kby.—Taken by Mr. Ashmead under bark of Pinus inops in an oval, cell-like depression prepared by the larva before pupating. Wedderburn, June, 1893. A rare species.
Acanthocinus nodosus Fab.–This large, showy species has been recorded to occur “under the bark of pine from June to September," in the neighborhood of Philadelphia (Proc. Ent. Soc. Phila., Vol. I, p. 97), and is ordinarily of rare occurrence. It was fairly abundant in the streets of Washington during the summers of 1894 and 1895. At one time a half dozen individuals were noticed under a single electric light, where they were being trodden upon by pedestrians. Without doubt this unusual abundance was due to the many dead trees killed by Dendroctonus frontalis in the vicinity.
PROBABILITY OF FUTURE DESTRUCTION OF FOREST AND SHADE TREES.
The severe windstorms that have swept over the South Atlantic States during the past year, particularly that of September 29, which was the severest ever known in this region and caused very extensive destruction of forest and shade trees, will doubtless result in still greater destruction to trees through the opportunities that the dead, dying, or injured trees afford for the propagation of injurious insects. It should be borne in mind that wood- and bark-boring insects generally prefer timber that has been recently killed, and that when this is not available they will attack injured, weakened, or even healthy growth.
PREVENTIVE AND REMEDIAL MEASURES CONSIDERED.
Such owners of forest land as have sufficient financial interests at stake will do well to clear up the dead, and trim the injured, trees. For the protection of chestnuts all dead oaks should also be cleared away and burned, and the same is true in the case of pines and other conifers. Much can be accomplished by simply removing the bark of the dead timber. The injurious species require as a rule a year for development. The first warm days of April and May will see the first numbers of the invading host upon the dead and injured trees. The succeeding month these will give place to other species, and by the end of July the most of these will have laid their eggs in cracks and crevices in and under the bark and have disappeared.
Unfortunately, in too many cases the storm-killed and injured trees will be carelessly permitted to remain as a nidus for borers, and when this wood becomes too dry and the bark too loose for the insects those that have bred in them will emerge and migrate to neighboring trees.
Before the following spring the progeny of these insects will have so loosened the bark that it may easily be removed and burned, thus destroying millions of the insects before they have an opportunity to issue and lay their eggs for the destruction of valuable trees.
In Europe in similar cases it is customary for foresters to girdle a few trees here and there and leave them standing as traps for such beetles as may not have been destroyed with their host trees. These trees in turn are decorticated the following year and others treated in like man. ner should appearances indicate the advisability of this course.
Some instances were noticed of chestnuts infested in dooryards and of a giant spruce near a public building. For the protection of valu. able shade trees against borer attacks other more direct measures may be employed. A light coating of raupenleim and dendrolene to the trunks and lower branches would answer the purpose of preventing the deposition of eggs at this point, which is the favorite place of attack, while a heavier application would prevent the egress of the insects from the bark should the trees already be infested. A wash of lime to which a small quantity of Paris green and a sufficient amount of glue to render it adhesive has been added would also serve a good purpose.
Whatever is used should be applied just before the first warm spell of spring. At the very outset of an attack a very thin application of kerosene, kerosene emulsion, or creosote by lightly brushing or spraying it over the infested parts would kill the beetles with which it came in contact.
A LEAF-MINER OF TOBACCO.
We have been in correspondence with Mr. Gerald McCarthy, of the North Carolina station, in regard to a leaf-miner in the tobacco fields of that State which may be a somewhat serious enemy to this important crop. From specimens of the larvæ received from Mr. McCarthy we were enabled to rear the moth, which has been determined for us by Miss Murtfeldt as Gelechia piscipellis Zell. This determination reveals, what we had from the first suspected, that the occurrence of the leaf miner in tobacco was simply an instance of change of habit, more or less accidental, and perhaps not permanent. We do not understand that the damage is widespread, but, on the contrary, that it is restricted to a single locality. Just as the plowing up of rank-growing sod land and planting it to corn frequently results in a serious attack upon the corn by root webworms, billbugs, and other insects, and just as the plowing up of a field overrun by pigweed has resulted in an attack upon the ensuing crop of sugar beets by the sugar-beet webworm, so the planting to tobacco of a field in which the horse nettle had been abundant would be quite likely to result in the transference of the attenions of the horse-nettle leaf-miners to the leaves of tobacco. Such cases are not apt to recur except under exactly similar conditions.
A GALL-MAKING COCCID IN AMERICA.
In Science for September 4, 1896 (Vol. IV, No. 88, pp. 299–300), Mr. T. D. A. Cockerell describes Olliffiella (n. gen.) cristicola n. sp. from specimens producing galls on Quercus wrightii, at Pinos Altos, N. Mex., collected July 8, 1896. The genus belongs to the Idiococcinæ, a group of sixteen known species, all confined to Australia, except one in the Sandwich Islands, one in Japan, and the present species.
The publication of this note reminds us that specimens of this same insect were sent to the Department of Agriculture as long ago as May 18, 1882, and that a figure was prepared of the gall by the late Dr. George Marx, at the instance of Dr. Riley. The figure has never been published, and is printed herewith (fig. 44). The notes made by Mr. Pergande on its receipt were as follows:
Received May 18, 1882, from H. K. Morrison, Fort Grant, Ariz., some galls on leaves of oak, which are produced by a brachyscelid coccid. This is the first species
For bibliographical purposes it should be stated that all unsigned notes may be credited to L. O, Howard.