Canker Worm.

Nearly four hundred apple orchards, containing over forty thousand trees, were examined in different sections of the State during May and the first part of June. Some of these orchards were large, but most of them covered only small areas. Many of the localities visited were those that had not previously been examined. The insect was found more abundant and destructive than last year. In some cases, the visits of the inspectors and the information given by them caused the owners to begin spraying operations, while others who were unprepared determined to take up the work next year. The inspection also resulted in the discovery of several outbreaks of the San Jose scale, which were unknown to the owners of the premises.

The following data, compiled from the reports of the canker worm investigations, is given, as it shows, approximately, the interest that is being taken in spraying by owners of small orchards:

Owners interviewed

Owners who do not spray.

Owners who have sprayed once and failed.... 20
Owners who have sprayed successfully, but

now neglect to do so.

Owners who spray regularly

..306

211 69 per cent.

6 per cent.

Among those who do not spray were found a small per cent. who believe that spraying pays and who propose to give it a trial. Many of the orchards, however, were declining, and not a few of the owners were so much discouraged that they proposed to cut out their trees. In some cases, orchards of fifteen or twenty acres had been destroyed, because of failure to control the canker worm. In most instances where spraying had proved a failure Paris green was used, and the treatment had been applied when the worms were nearly developed. Six per cent. of the owners had sprayed with good results, and had either been so successful in controlling the canker worm that they thought it unnecessary to apply treatment another year, or they had neglected to do so for various reasons, although being firmly convinced that it was a profitable and necessary undertaking.

More than one spraying should be applied to control the codling moth, even if no canker worms are present in the orchard, and it is as necessary for profit to secure clean fruit free from worms as to keep the leaves in a healthful condition. For best results, attention must be given to both insects.

Of the fifty-seven owners who sprayed regularly, two used London purple, forty Paris green and fifteen disparene. The more progressive and successful growers had abandoned the use of Paris green and had

44 O. S. B. of A.

found disparene more satisfactory. Good results had in many cases been secured by using Paris green; London purple was pronounced by many as very unsatisfactory.

The lesson to be drawn from this data, and it is particularly applicable to parties who expect to plant small orchards, is that there can be very little hope of success unless the best modern methods are studied and applied to the management of their trees. If an owner is unwilling to do this he should invest his money in some other line to which he will give his best thought and attention.

Tent Caterpillar.

During the canker worm investigations, the tent caterpillar was found to be doing considerable damage in the western and northwestern counties of the State. No difficulty will be encountered in controlling this insect if spraying is applied as directed for the canker worm.

San Jose Scale.

Many city lots and small orchards have been visited during the year, on the request of the owners, in order to determine whether this insect was present. In a few cases it had been confused with the scurfy scale, but where the San Jose scale was found all information possible was given the owners, so that they could take measures to protect their trees. Since the last report was made, San Jose scale infestation has been reported from twenty orchard localities in different parts of the State. It has also been found in the following cities and towns: Florida, Leesburg, Napoleon, Norwalk, Ostrander, Sandusky, Sycamore, Upper Sandusky and West Carrollton.

The report concerning a number of these infested localities has been received through the courtesy of the Ohio Agricultural Experiment Station.

Natural Enemies of San Jose Scale.

The colony of Asiatic lady birds, which was located in Clermont county in August, 1903, survived the winter, but after the first examination of the orchard last spring the beetles disappeared; whether this was due to the presence of their native enemies or to birds it is not possible to say, but at the present time, as far as we have been able to determine, the colony is extinct.

Investigation of Grape Pests.

For many years the vineyards along the lake shore have been injured by insect pests and plant diseases. These seem to increase annually in number, and, at the request of the growers in the vicinity of Euclid, at series of observations was made during the spring of 1904, to determine the extent of the damage and the pests that were directly responsible for it. This work was placed in charge of my assistant, Mr. Otto H. Swezey, who made a number of visits and spent considerable time in this vicinity during June and July. Unfortunately for this work, Mr. Swezey resigned late in July to accept a flattering offer as Assistant Entomologist to the Hawaiian Experiment Station, at Honolulu, H. T., so the work could not be carried through the season, in accordance with the original plan.

Enough data were obtained, however, to indicate the presence of most serious pests and to make suggestions as to the best methods of combatting them. It is the intention to continue this work next season and make tests, with a view of obtaining cheaper and more satisfactory remedies.

The owners of vineyards in the vicinity of Euclid are fortunate in that very little trouble has been experienced with the grape rot, which in other sections of the grape belt, especially further to the east, has been seriously injurious for several years and this has been one of the immediate causes for the destruction of many vineyards. On the other hand, this locality has suffered much from the ravages of the grape root worm, while the eastern section of the grape belt has not been seriously affected by this pest.

It was found that considerable confusion exists concerning the identity of the insect pests which injure this crop, and in some cases reports of injury by the root worm were found to be due to the presence of the grape berry moth, an entirely different insect.

From the data collected and observations made by Mr. Swezey, it appears that the grape root worm was not as abundant or destructive this year as in the past, and this was found to be true in unsprayed, as well as sprayed, vineyards, and also where the vines had been neglected and the vineyards practically abandoned.

The grape berry moth was present in many vineyards and caused serious injury. Last year nearly 30 per cent. of the crop was ruined in some vineyards, and the loss this year was fully as great.

A New Grape Pest.

About June 10, 1904, Mr. John Maxwell, of Euclid, noticed that some of the blossom buds on his vines had become enlarged and were turning red; also, that on opening such buds several white or yellowish worms were found. On the arrival of Mr. Swezey at this vineyard his

attention was called to the matter and an examination showed that the worms were the immature stage of a small fly, which, as far as can be determined, is a newly discovered insect.

The buds thus affected fail to develop berries and this makes the clusters irregular in form and causes considerable loss. An examination of many vineyards, both on the high land and in the flat localities nearer the lake, showed that the insect was generally distributed throughout. In some cases nearly one-fifth of the clusters were infested, and as many as twenty-five affected buds were found in a single cluster. As the minute larvæ drop to the ground, and evidently complete their transformations in the soil, it is a difficult matter to rear them to the adult stage. From their structure, however, it is evident that they transform into tiny flies, which closely resemble adult Hessian flies.

No treatment for the control of this insect can be suggested at this time, but further investigations may serve to discover a remedy. Mr. T. S. Clymonts, and several other progressive growers in this section, state that they have observed the work of this insect for several years, but believed it to be a stage of the grap berry moth.

This new pest was found in the Chautauqua grape belt in New York on June 12, 1904, by Mr. Fred Johnson, who was working on grape pests with Prof. Mark V. Slingerland, Entomologist to the Cornell Experiment Station. I am also informed by Dr. E. P. Felt, State Entomologist of New York, that he has found it in many vineyards this year.

The Elm Leaf Beetle.

This insect was discovered in Dayton by Mr. George A. Runner, one of my assistants, while engaged in nursery inspection work in that vicinity. Specimens were received by me August 30, but as they were in very poor condition a visit was made to Dayton early in September. Accompanied by Mr. Runner, an examination was made of the elm trees on the grounds of the National Cash Register Company, where the specimens had been obtained. Larvæ, pupæ and adult beetles were also found on adjoining premises and on the grounds of the Montgomery County Agricultural Society. The managers were notified and they promised to do everything possible to check the pest. Later in September an examination of the city trees was begun. This resulted in the insect being located in nearly all sections where elm trees had been planted. Observations made in many cities in the State have failed to reveal the presence of this insect, but it probably occurs in other localities.

It is not a native species, but was introduced into this country from Europe several years ago. In many cities and towns in Massachusetts, Connecticut and New York, the elm trees have been so severely attacked that it is necessary to spray them annually, in order to protect the foliage. Owing to the size that these trees grow, this is a difficult and expensive operation.

The beetle resembles very much the common striped cucumber beetle. It makes small holes in the leaves, which are often eaten to such an extent that very little remains except the veins. The larvæ, or immature form of this insect, feed upon the green tissue of the leaf, so that affected trees have a peculiar appearance, which is very characteristic. Feeding begins soon after the leaves appear in the spring and continues until late in the fall, and, as the insects are very prolific, serious damage may be done in a single season.

The European elm appears to be the favorite food plant of this pest, although many cases have been noticed where American elms have been seriously attacked.

The most successful remedy, and the one almost universally used against this pest in the east, is to spray the trees early in the summer with disparene or arsenate of lead, using five pounds to fifty gallons of water. During the summer, the trunks and ground at the base of the trees often harbor many larvæ and pupæ, and these may be destroyed by applying a weak solution of kerosene emulsion, whitewash, or whale oil soap mixture, used at the rate of one pound of soap to four gallons of water.

From the general distribution of this insect in Dayton, it is evident that energetic measures will have to be taken in the near future to protect the elms from this pest, as no tree is able to withstand continual defoliation. Trees in Dayton have been found completely stripped of leaves, and in one instance a second crop of leaves had started and was being devoured.

TESTS OF REMEDIES.

Many tests have been made during the past year for the control of insect pests and plant diseases. Among the principal ones may be mentioned, comparative sprayings with Paris green and disparene for the control of the codling moth, treatment with various modifications of the lime and sulphur wash for San Jose scale and other insects and numerous tests with hydro-cyanic acid gas.

Aside from the San Jose scale, the codling moth is the most serious insect pest with which the apple grower has to contend, and, although spraying has been recommended for years and is practiced by the more progressive growers, the question as to the best time of making treatments and the cheapest and most satisfactory poison to use still remains unsettled. Nearly four hundred trees were treated this year, but only a few of the results will be given in this report. The advantages of disparene over Paris green were manifest, and the necessity of making a spraying late in July for the control of the second brood of moths was demonstrated.

Treatment for San Jose scale consisted of applications of the lime and sulphur washes with various modifications, including the use of