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trees on which they were introduced, although they had been in the orchard since the spring of 1894. All of the trees that the scale was found on came from a New Jersey nursery, but it was certain varieties of trees only that were infested, the Idaho pear being the principal and almost only we infested, while in some instances hundreds of trees purchased at the same time and of the same nursery were found, after a careful search, to be perfectly healthy and free from the scale.
My instruction in each case where I liave been consulted has been to grub up and burn every infested tree, and so far as I can learn this has been done.
There are doubtless other localities in the State, however, where the scale occurs, but where it has not been recognized, so that every effort will be made to find other localities and to prevent the spread of the pest in the State.
The scurfy vark-louse (Chionaspis furfurus).—It would appear that this scale is quite common and widely distributed in this State, since it has been sent in from many different sections. The oyster shell bark louse is also common and quite destructive in some sections, principally within the range of the transition zone.
The rose scale, the plum scale, and other insects, and even twigs the bark of which was covered with prominent lenticels, were sent in by persons who thought they might be the dreaded San Jose scale.
Cutworms (not the Hopkins variety of newspaper fame, but those having normal transformation and feeding habits) were exceedingly common and destructive in our State in the spring and early summer of 1895, but, as was predicted, they gave comparatively little trouble the past spring. This scarcity of the pest this year is due, I think, largely to the abundance last year of an Apanteles parasite that emerged from the cutworms in enormous numbers. So abundant were the conspicuous yellow or white bunches of the cocoons on grass and grain stubble and on weeds and grass in pasture fields near Morgantown and other localities visited last summer that in places I could count hundreds of them within a radius of a few yards.
The webworms (crambids).—These insects attracted general attention for the first time last year, and were serious pests in cornfields and gardens.
The harlequin cabbage bug has proven to be a serious pest in certain sections of the State within the past few years. It was quite destructive to cabbage in the experiment station garden last year, but scarcely a single example has been observer this year until quite recently. Whether or not this early absence of the bug is due to the late fall and winter plowing of the garden I can not say, but it would appear that such may be the fact.
Blister beetles as enemies of China asters.—Last summer a fine bed of assorted and rare China asters growing in the experiment station flower garden was literally ruined by the black blister beetle (Epicauta pennsylvanica) within a day or two after the flowers began to open. It
was therefore determined to find some method of protecting the blooms this year, so I recommended covering them with mosquito netting stretched over a temporary frame. This was done, and proved quite successful until all the flowers bad opened and some were beginning to fade, by which time the beetles (which occurred on the netting in great numbers all the time the asters were in bloom) learned that they could get in by eating holes in the netting, and they soon availed themselves of this method of entrance and feasted on the flowers. The holes would probably not have been eaten in the netting had not some of the flowers pressed against it, thus allowing the beetles to feed through the covering. A higher frame covered with netting which had been previously dipped in oil wonld have proven successful.
A chalcidid enemy of clover seed.—June 13 of the present year (1896) I observed a great many examples of what I first supposed to be a Eurytoma parasite in and on a paper bag in which some ripened heads of crimson clover had been stored. Upon close examination to find their host insect I was thoroughly surprised to find that it was not a parasite of an insect, but that it bred in the seed, and that scarcely a seed could be found in the bag that had not been a host of one of the interesting little creatures. Specimens of the insect were sent to Mr. William H. Ashmead for determination, who kindly identified them for me as Bruchophagus (Eurytoma) funebris How. By reference to the literature on the habits of the species I found that it had previously been bred from clover seed and was generally recognized as a parasite of the clover-seed midge (Cecidomyia leguminicola), and that it was believed to be especially beneficial in diminishing the ravages of the midge.
This information led me to make a careful examination of a large number of infested seeds, but as yet I have failed to find any evidence whatever that it is a parasite of the midge or any other insect, but, on the contrary, quite conclusive evidence was found that it is a parasite of the seed. It would also appear from what I have observed that it is far more destructive to the growing red and crimson clover-seed crop than is the midge.
Larva of the clover-seed midge were observed in some of the clover heads examined, but since the Cecidomyia larv:e prevent the development of the seed, while the chalcidid larvæ develop within the seed which attains normal size, the two species can no longer be associated as host and parasite.
Bumblebees and red clover.-In a recent study of varieties of timothy and red clover I deemed it necessary to make some further investigations with reference to the pollenization of the clover flower and the relation of insects to the crossing of varieties, and it would appear from the results obtained that the value of bumblebees to the grower of clover seed has been somewhat overestimated, since I have found that honeybees and other smaller bees may and do serve the same purpose in pollinating or cross-fertilizing the red-clover flower as do the large bumblebees.
Mr. Webster, referring to the subject of the setting of clover seed, said that in his experience a good crop of seed always followed an attack of the clover leaf-weevil, and, therefore, the latter insect is often actually a means of putting money into the pockets of the farmers.
Mr. Howard read a paper entitled “Remarks on steam spraying machines,” which will appear in full in the Yearbook of the Department of Agriculture for 1896.
Some discussion followed on the subject of nozzles, the experience of different members with various nozzles being given. The "cyclone" nozzle was objected to by some on the ground of its lack of sufficient carrying power. The McGowan nozzle liad not always given good satisfaction. The Nixon pozzle was also mentioned. The general opinion seemed to be that the “cyclone” nozzle was the best for all ordinary purposes, supplemented with the Nixon and McGowan for spraying larger trees.
Mr. Webster stated that inquiries were beginning to come in from farmers and orchardists for a steam-spraying apparatus and that he was convinced that as soon as a practical machine was put on the market it would be in great demand.
Mr. Fernald said that the botanist of the Massachusetts Station, at Amherst, had been using some sort of steam-spraying apparatus and regarded it as a success.
Mr. Howard stated that a very satisfactory apparatus could now be had for about $300, which was considerably less than first estimates.
All of the papers the authors of which were present having been read, and the hour being late, on motion of Mr. Howard, it was ordered that the balance of the papers in the hands of the secretary be read by title and left to the executive committee to determine whetheror not they should be included in the published report of the proceedings. The committee deemed all the papers in question worthy of publication, and they are here included.
NOTES ON NEW AND OLD SCALE INSECTS.
By W. G. JOHNSON, College Park, Ud. In December, 1894, I discovered a scale insect on cherry trees at Champaign, II., which, on account of the nature of its attack, I consider a very important economic species. After a careful study of a large amount of material and much correspondence with Dr. L. O. Howard and Prof. T. D. A. Cockerell, I believe the species is new to science and have described it as Aspidiotus forbesi and have given it the popular name of the cherry scale. The description of this species, together with four others mentioned below, will appear in an illustrated article soon to be published in the Bulletin of the Illinois State Laboratory of Natural History, Vol. IV, Art. XIII.
I consider the cherry scale the most dangerous scale insect now established in Illinois. It has a variety of food plants, but wild and cultivated cherry seem to be its favorite. I have found it also on apple, pear, plum, quince, currant, and possibly honey locust and mountain ash. It attacks the trunk and branches and is occasionally found on the leaves and fruit. In June of the present year I found several imma. ture scales ou cherries. July 6, 1895, I collected several currants on which scales of this species were found, and August 14, 1895, I gathered apples from the Illinois Experiment Station farm containing scales of fully matured females.
It hibernates as a partially matured insect and is double brooded in the latitude of Springfield, 11. The mature males begin to appear
Ill about the middle of April and the first brood makes its appearance early in May. It is not an uncommon thing, however, to find young and eggs as late as June 20. The mature males of the second brood begin to appear about July 10 and continue to einerge until about the first of August. I am of the opinion that there are three broods in extreme southern Illinois. It is related to Putnam's Aspidiotus ancylus, but inay be readily distinguished from that species by the second pair of lobes of the last segment of the female, the number of spinnerets and other characters presented by the adult male, and the scales of both seses.
This pest, however, is by no means free from the attacks of natural enemies. I have reared from it seven species of hymenopterous parasites, determined for me by Dr. L. (), Howard, as follows: Prospalta murtfeldti How., Prospalta aurantii How., Perrisopterus pulchellus How., Signiphora nigrita Howard MS., Arrhenophagus chionaspidis Aur., Ablerus clisiocampe Ashm., and a species belonging to the genus Encyrtuis. The twice-stabbed ladybird (Chilocorus birulnerus) and its larva are very important factors in the reduction of this scale insect. I have very often found a small whitish mite under scales containing dead male pupæ. Whether the pupa had been killed by the mites or whether they had been attracted there by the presence of the dead insect I have not been able to determine as yet.
In spite of its natural enemies it has a firin foothold in Illinois, and can be kept in check only by the most energetic and persistent fighting. It is not an uncommon thing to find 7 and 8 year old cherry trees in that State literally covered with this destructive scale. It is also present in certain nurseries in Illinois, as I know from personal inspection. It is of great consequence, therefore, to all those interested in fruit culture to be on the lookout for this ravenous pest.
I wish to call your attention to three other species of Aspidiotus recently described by myself. Only one of these, liowever, is of much consequence from the economic standpoint. I have proposed to call it Aspidiotus comstocki in honor of my teacher and friend, Prof. J. II. Comstock, of Cornell University. It has been very abundant for several years on sugar maple (Acer saccharinum) in Illinois, at Mount Carmel, Decatur, and Champaign. I found it also on maple in Ohio, at Columbus, the early part of July, this season, and have had it from Mr. R. H. Pettit, who collected it on maple in Ithaca, N. Y., two years ago. It attacks the leaves, living in great numbers on the under side, causing yellowish spots on the upper surface. The spots are minute at first, but become more prominent as the insect develops and the season advances, causing the leaves to fall prematurely. The partially-matured insects spend the winter under the leaf buds. I have found it only on maple, and as it attacks the leaves principally I have proposed the popular name of the maple leaf scale, to distinguish it from other allied species. It is related to the grape scale (Aspidiotus uvæ Comst.), but may be readily separated from that species by its yellowish-gray or whitish scale and the structural characters of the male and female.
Of the other two species I found Aspidiotus ulmi on the trunk of white elm (Ulmus americana) at Urbana, III., about a year ago in rather limited numbers, and so far as my observations go it does not attack the branches, twigs, or leaves. I found the other species, Aspidiotus asculi, on buckeye (Esculus californica), at Stanford University, Cal., three years ago. It attacks the trunk, branches, and smaller twigs, but so far as I have observed does not occur on the foliage. The color of the scale usually conforms to that of the bark, and when not abundant the insect is difficult to detect.
In February, 1895, the markets of central Illinois were stocked with California oranges of a very inferior grade. The local dealers at Champaign sold them for russet oranges. The russetness, however, was due to a complete covering of the red scale, Aspidiotus aurantii Mask. The consumer paid 40 cents a dozen for this tasteless fruit.
August 8, 1895, Mr. G. W. McCluer, of the Illinois Experiment Sta. tion, handed me a lot of apple grafts from A. Woodroffe, Auckland, New Zealand, for examination. I found Aspidiotus camelliæ Bois., the greedy scale of Comstock (= A. rapar), upon five of the seven varieties repre. sented. The scales were attached usually under the buds. The females were fully matured and an occasional young louse was found on the twigs. This scale is widely distributed in this country, and, according to Maskell, is common throughout all the North Island of New Zealand, and in parts of the South, on enonymus, apple, plum, and other trees.
Early in August a year ago I found Putnam's Aspidiotus ancylus on English oak (Quercus robur) in Urbana, Ill. The attack was confined to the under side of a few of the lower branches. This season the insect bas spread to all the larger and smaller branches, and many of the lower branches have died, being literally covered with this insect.
Aspidiotus nerii was very abundant on certain plants in the greenhouse at the University of Illinois early this season. It was particu larly destructive to the so-called lace fern (Asparagus plumosa).
The English-walnut scale (Aspidiotus juglans regice) is very cominon on the white or silver maple (Acer dasycarpum) in Illinois. I have also