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Spraying with Paris green or London purple in the proportion of 1 pound to 125 to 150 gallons of water as soon as the young larvæ are noticed, or a week or ten days after the moths appear in the spring, is at once the simplest and most effective remedy, Apparatus suitable for this work has been repeatedly described and illustrated in various publications of the Division, and now that the benefits of spraying against nearly all insects have been so conclusively and repeatedly shown, such apparatus should certainly be in the possession of every progressive farmer or orchardist, and also of every municipality. The initial cost would be more than saved the first season. For spraying large trees an ordinary direct discharge nozzle will answer very well, or, better still, the Nixon nozzle, made by A. H. Nixon & Co., Dayton, Ohio, from whom also a complete spraying outfit may be obtained if desired. If the larvæ have been allowed to reach full growth so that spraying will be of no use, great numbers of them can be entrapped and easily destroyed, as stated in the report cited, by digging a trench either around the individual trees or around the groves or belt. The trench should be at least a foot deep, with the outer wall sloping under. The larvæ usually wander from the trees before entering the ground, and will collect in numbers in the trench or bury themselves in the bottom, and may then be easily killed.
Their numbers may be reduced also by keeping a sharp lookout for the moths and eggs during the latter part of May, when both may be destroyed in large quantities.
A NEW PEACH PEST.
(Ceratitis capitata Wied.) Order DIPTERA; Family TRYPETIDÆ.
[Plate III, Figs. 1 and 2.] A dangerous enemy to the peach crop exists in Bermuda, as we have ascertained during the past season, and the frequent importation of fruit from that island to this country renders possible the introduction at any moment of this injurious insect into our territory. We have, therefore, taken some little pains to ascertain all that is known about it. Our material has been furnished us by Mr. Claude W. McCallan, of St. George's, Bermuda, and a preliminary article upon the species was published by us in INSECT LIFE, Vol. III, No. 1, August, 1890. The insect is a two-winged fly of the family Trypetidoe, and is allied to the apple maggot (Trypeta pomonella) of this country.
Infested peaches were received from Mr. McCallan in April, and early in May the adult flies were reared and proved to be the Ceratitis capitata, long since known as a pest to the orange crop in various parts of the world, but not yet found within the limits of the United States. The regions most affected are the East Indies and the Azores Islands, where the insects abound upon citrus fruits. The same or a closely allied species is found upon the Island of Malta, and is at present being investigated by a committee charged by the governor of that English possession with the preparation of à report. In Spain, Algeria, and Sicily a species known as C. hispanica, but which may possibly be the same insect which we have under consideration, has been found and has been studied recently by Dr. O. Penzig in Sicily. The female penetrates the skin of the half-grown orange and lays her eggs at the depth of from 1 to 3 millimeters and in a few days the larvæ hatch and burrow through the skin and into the pulp of the fruit, rendering injured fruit partly recognizable by a brown or olive spot, which soon extends to from 3 to 5 centimeters in diameter. The original puncture is always noticeable and the larva returns to it frequently for air, placing its anal spiracles against the opening. The orange soon falls to the ground and in the space of fifteen days, more or less, the larva issues either through the original opening, or through another one made for the purpose, and enters the ground, where it transforms to pupa, remaining in this condition only a few days. There are presumably a number of annual generations. The orange is preferred to lemons and other cultivated citrus fruits, which are, however, attacked, as also peaches, figs, and azaroles. Curiously enough in Liguria Dr. Penzig found it damaging peaches, but he was not able to verify its presence in oranges or lemons. The remedy proposed was to coilect and destroy the infested fruit or to submerge it for a short space of time in water. As a means of destroying infested fruit le proposes to place it in a ditch, cover with a layer of caustic lime, and thus convert the whole mass into a valuable fertilizer.
In Bermuda the species which we are considering seems to have the same peculiarity as that observed by Dr. Penzig in Liguria, in that it has forsaken citrus fruit for peaches and probably for Surinam cherries, mangoes and probably also for the Loquat or Malta plums. It has been known to infest the peach for twenty-five years but has not actually been reared so far as we can find from any other fruit. At our request Mr. McCallan searched for the flies upon the citrus trees and found a few specimens lodging upon some lime trees and fruit. No damage to this fruit, however, seems to be known in that locality. Oranges and lemons are very little grown owing to diseases of every kind and in particular (judging from Mr. McCallan's description) the foot rot (mal de goma) and rust. It is not unlikely that this partial abandonment of citrus culture and the destruction of the trees from disease was the cause of the transfer of the attention of the Ceratitis to peach. Just at this time of writing, however, we have received a letter from Mr. McCallan who states that he has been informed by a Mr. Swainson, a reliable man and a great observer of nature, that he had in his yard some bitter Seville oranges, from which marmalade is made, so badly attacked by this fly year after year that he cut the trees down. Other persons living in the vicinity where this sour orange is to be found wild and who market the fruit at Christmas time for the purpose of making marmalade told Mr. McCallan that they had never seen any of the oranges injured in the slightest degree by the maggots which are to be found infesting the peach.
Owing to damage done to the peach crop many persons have cut down their trees and peaches are now comparatively scarce, although formerly they were most abundant and could almost be said to grow wild. This tree blossoms in January and when the fruit is one third grown it is punctured by the fly. It continues to grow but instead of ripening suddenly becomes quite soft and decayed and drops from the tree to the ground full of maggots and perfectly useless. The insect is shown upon Plate II in all of its stages. The larva leaves
the fruit and to transform enters the ground from one fourth to 2 inches below the surface. The development is very rapid and there must be from six to eight generations in the course of a year provided food is at hand, and when peaches are not obtainable the other fruits just mentioned will without doubt be attacked. The Surinam cherries and mangoes ripen during the summer months while the Malta plums blossom in October and ripen about the following March. These fruits, therefore, with the Peach, will suffice to carry the insect through an entire season.
Owing to the fact that the female deposits her eggs under the skin of the fruit, the application of arsenical poison will be of no avail, but the collection and destruction of the fruit through any one of the ways proposed by Dr. Penzig will prove an adequate preventive provided it is done in concert over a given neighborhood and thoroughly done. It will not suffice to simply collect and destroy fallen peaches, as from Mr. McCallan's information the Malta plums are in fruit at the same time. The latter, therefore, should be also watched and all fallen fruit gathered and destroyed. There may be other fruit infested by the same insect which will also have to be watched and in localities where the Surinam orange grows it will also be fruiting at the same time and examination should be made for the purpose of ascertaining whether this fruit is also infested.
Mr. McCallan is of the opinion that the insect was originally in+roduced into Bermuda during the American civil war in cargoes of fruit brought from the Mediterranean region. These cargoes were intended for the American market but from stress of weather and other causes the vessels had to put in at Bermuda for repairs, etc., and the insects finding a congenial habitat, flew out and began to reproduce.
Judging from what has been written about this species it is a tropical insect and there is consequently little danger that it will thrive in the Northern States, but peaches are grown extensively in Georgia and many fruits which are liable to be attacked are cultivated in Florida. “Although peaches are not now received in bulk from Bermuda, the accidental importation of the pest is always possible. Once imported into Florida its extermination would be almost impossible. We send out this note of warning for the benefit of those interested.
THE ROSE CHAFER.
(Macrodactylus subspinosus Fabr.)
Order COLEOPTERA; Family SCARABÆIDÆ.
[Plate V; Figs. 1 and 2.] Inasmuch as we have not hitherto treated of this notorious insect in any of the annual reports of this Department we have thought best to introduce here a condensation of an article which we published in the April number of INSECT LIFE (Vol. II, No. 10), and which gives a fair summary of the life history of the species with an account of the remedies. Some account of this insect is particularly timely in the present report for the reason that the season of 1890 since the publication of the original article) has been marked by an extraordinary abundance of this insect in certain sections. Some
points brought out in our own correspondence during the summer and by the work of other entomologists, particularly Professor Smith, of the New Jersey Experiment Station, will also be referred to.
According to Harris the female beetle lays her eggs to the number of about thirty, about the middle of July, at a depth of from 1 to 2 inches beneath the surface of the ground. He does not state the favorite place for oviposition, but in our experience the larvæ are especially abundant in low, open meadow land or in cultivated fields, particularly where the soil is light and sandy. Harris states that the eggs hatch in about twenty days, and, while the period will vary with the temperature, the larva is found fully grown during the autumn months. With the approach of cold weather it works deeper into the ground, but in the spring will frequently be found near the surface or under stones and other similar objects, where it forms a sort of cell in which to pupate. In confinement the pupa state has lasted from two to four weeks. The perfect beetle issues in the New England States about the second week of June, while in the latitude of Washington it is seen about two weeks earlier. It appears suddenly in great numbers, in conformity with the habits of other Lamellicorn beetles, e.g., our common May beetles (genus Lachnosterna). It remains active a little over a month and then soon disappears. The species produces, therefore, but one annual generation, the time of the appearing of the beetle in greatest abundance being coincident with the flowering of the grapevine.
FOOD PLANTS AND RAVAGES. The food of the larva consists of the roots of grasses and probably also of other low plants. Whether it also feeds on the rootlets of trees and shrubs has not been definitely ascertained, although the larvæ have been found quite numerously around the bases of oak trees, near Washington, both by Jr. Koebele and Mr. Schwarz. We found them quite numerous in the sandy lowlands of the Merrimac Valley, New Hampshire, on cultivated ground, where they must have fed on the roots of various weeds or on those of meadow grass and cultivated rye and maize. It is probable, however, that they occur yet more numerously in unplowed pasture and meadow land than in cultivated fields. We have also recorded the fact that they exceptionally feed upon the egg-pods of the lesser migratory locust or grasshopper (Caloptenus atlanis). The beetle has a partiality for flowers, but also feeds upon leaves of various trees and bushes and attacks certain fruits. It has a predilection for the flowers of roses, wild as well as cultivated,* and, in the experience of many observers, prefers white roses to red ones. Harris states that the beetle was first noticed on the rose (hence its popular name), and that it afterward acquired the habit of feeding on grapevines and fruit trees. Another favorite food is the blossom of tho grapevine, with a decided preference for that of the Clinton. Flowers of raspberries and blackberries do not escape its ravages. Mr. E. H. Miller states, in the American Agriculturist (see Amer. Nat., v. 17, 1883, p. 1291), that the flowers of Deutzia, scabra are even preferred by the beetle to those of the grapevine. The blossoms of the various
* The Cinnamon Rose (Rosa cinnamonica) is said to enjoy immunity.
species of Spiræa are often crowded with the beetles, and the same may be said of the blossoms of the sumach, the common ox-eye daisy, Magnolia glauca, mock orange, and some other plants. This list could be greatly extended, but we close it with the statement that the beetles also devour the blossoms of Pyrethrum cinerariæfolium.
The foliage of most, if not all, of our cultivated fruit trees, and especially apple, pear, peach, cherry, and plum, at times suffers greatly, the two last-named trees being apparently more attractive than the others. The foliage of cultivated grapevines is almost as eagerly devoured as the blossoms, and the leaves of oak, alder, and other forest trees also serve as food. Of low-growing plants the beetles cut the leaves of strawberries, rhubarb, and of nearly all garden vegetables, as also of sweet potato, corn, wheat, grass, and many wild plants.
Not satisfied with this amount of damage, the beetles attack the fruit of peaches, cherries, apples, and grapes when just forming.
The statement that the beetle is poisonous has no foundation in fact.
It has been assumed by most writers that we can not successfully attack the rose chafer in any of its earlier stages. To search for the eggs in the ground would be impracticable. It does not, however, follow because of the poor success that has generally resulted from attempts to destroy similar larvæ that they can not be successfully destroyed. In the case of the common European cockchafer (larva of Melolontha vulgaris and hippocastani) and of our own white grub (Lachnosterna fusca) the methods adopted have consisted of plowing and hand-picking. The experiments made, however, on a similar larva with the kerosene-soap emulsion, as narrated in INSECT LIFE (Vol. I, p. 48), clearly show that we have in this insecticide a means of successfully destroying the bulk of the larva of the rose bug wherever they are known to be sufficiently abundant to justify such treatment. ' A thorough investigation should be maile in the direction of ascertaining the preferred breeding grounds of the species, and it were rash to say here that we have no effectual mode of preventing the insect, notwithstanding the disfavor in which this mode of warfare has been held in the past.
It is evident, however, that for the present we should concentrate our efforts on the destruction of the beetles especially when they first issue from the ground and congregate in the garden on our roses, grapevines, and fruit trees. A brief statement of the various methods that may be employed for this purpose may prove advantageous. Hand-picking and killing the beetles either by crushing them or throwing them into hot water, or water having a scum of kerosene upon it, has proved useful and satisfactory in a limited way, as also the shaking and knocking down of the beetles into pans or upon sheets saturated or smeared with coal oil.
These measures are best carried out and most satisfactorily in the early morning hours and toward evening, as the beetles are then more sluggish and not so quick to take wing as they are during the heat of the day. Whito roses, Spiræas, or Deutzias, planted on a place, will attract great numbers of the beetles, and thus not only facilitate the destruction of these last, but act as a kind of protection to other plants,