Blackberry Psyllid

(Troiza tripunctata)

An unusual attack on wild or escaped blackberry occurred at Central Lake. The attack was made on the site of an old nursery. On the 26th of August, 1925, Mr. W. C. Bennett of the Department of Botany was attracted by the peculiar curled and stunted leaves which led to the discovery of the psylla. It is hoped that the invasion will remain localized, since the tightly curled leaves would undoubtedly offer difficulties to one spraying the plants.

Cherry Fruit-fly

(Rhagoletis cingulata)

Continuing the inquiry into the habits of the cherry maggot in Michigan, preparations were made for the expected appearance of the flies during the season of 1926. Large cages of cheese-cloth stretched over light wooden frames were established at various important points in the western fruit belt. These cages were made without any floor, and were designed to prevent the

Fig. 14.-Cage for catching Cherry Fruit-fly at emergence from soil.

escape of adult flies (adults of the cherry maggot) as they emerged from their winter quarters underground. These covered frames measured ten feet by five feet and were two and one-half feet high. They were placed under unsprayed trees, the fruit of which had presumably been well stocked with maggots last summer.

Through the kindness of the following gentlemen, all of whom are prominent in the canning industry, cages were established at the following places: Benton Harbor, cared for by Mr. William Godfrey. South Haven, cared for by Mr. William Ewing. Fennville, cared for by Mr. M. C. Hutchinson. Kent City, cared for by Roach Canning Company.

Fremont, cared for by Mr. Dan Garber.

Hart, cared for by Roach Canning Company.

Traverse City, cared for by Grand Traverse Packing Company.

It is of interest to note that specimens collected by sweeping the cherry trees with insect nets announced the emergence of the adult flies at practically the same dates as observations made from the cages. In other words, we have two almost equally reliable methods of determining the date of emergence, and consequently the date for spraying-one by means of traps or cages which detain the flies as they come from their underground quarters, and the other by collecting the flies after they have settled on the fruit and foliage of the cherry trees.

As this report is intended merely to include events occurring up to July 1, 1926, the results of these investigations will be reported later. A report of progress on the project of cherry-maggot control for the summer of 1925 was published in Circular Bulletin No. 86. During the summer of 1926, the

field work and observations at the canneries was ably cared for by two assistants of the Department of Entomology, Mr. Sid Robinson and Mr. G. S. Tolles.

It is planned to establish more cages for the season of 1927, and in anticipation, preparations have been made by distributing quantities of maggoty cherries on areas staked out as locations for the emplacement of cages next year.

It is perhaps not anticipating too much to state that Michigan can thus far boast the presence of but one species of the cherry fruit-fly, Rhagolitis cingulata. This species normally emerges later than its relative R. fausta, in less favored states. Furthermore, the dates of emergence during 1926 in Michigan were later by considerable than was to be expected from the stage of development of the fruit as compared with observations made this year in the East.

Army-worm of the Forest
and

The Apple-tree Tent-caterpillar

Both of these species were present in force along the western coast from Oceana county to the Straits. They resemble each other in general appearance but they differ markedly in habit. The tent-caterpillar spins a close-felted web in the branches of various trees, seeming to prefer wild cherry to others. It is ordinarily only slowly controlled by parasites so that when it once establishes itself, it usually flourishes for several years before finally it is wiped out. It travels freely after it becomes half grown, and from that time on it is apt to fail to return to its "tent" or web for the night, although during the first part of its larval existence the nest is sure to be utilized in this manner.

The army-worm of the forest, on the other hand, spins only a very tiny nest, one that is hardly noticeable, and the young travel freely at an early age, although they are likely to remain in each other's company for quite a few weeks. Fortunately this species is freely parasitized and seldom occurs in great numbers for more than one or two seasons. When full-grown they have a habit of wandering, sometimes by the thousand, along railroad tracks and fences before spinning the light yellowish cocoons in which they transform to adult moths. The winter is passed in the egg stage, the eggs being cemented into a ring of gummy substance which surrounds a twig. Both species deposit their eggs in this ring form, the tent-caterpillar building an egg ring or band which is rounded at the ends, while the army-worm of the forest builds one which ends squarely. Both species may be controlled in orchards by means of the ordinary arsenical sprays, and in the case of the tent-caterpillar one can supplement the sprays by burning the nests which usually abound in adjacent wild cherry trees. This is facilitated by first saturating the nests in such worthless trees, with kerosene applied as a jet by means of a knapsack sprayer.

Gibson's Hen-flea

(Ceratophyllus gibsoni)

It would appear that a parasite of poultry, new to the United States, has appeared in Michigan, in the form of a flea. This tiny pest differs but slightly in the eyes of the casual observer from the common cat-flea. It was brought in by Mr. Ballard of the College Extension Department, who collected a quantity in a poultry house at Palms, Michigan. Mr. Ballard reports that the creatures swarmed over the hand when one searched for eggs. Ordinary measures seem to have controlled the pests. Spraying the interior of the building with a miscible oil, and the use of Pyrethrum in the nests was recommended. No doubt sodium fluoride would have been equally effective, although not so easily obtainable.

The species was determined by Dr. H. E. Ewing of the United States Bureau of Entomology. The only other finding of the species in America was made by Mr. Arthur Gibson in Ottawa, Canada.

A pest of bulbs new to Michigan has finally appeared. Presumably it is still rare in Michigan, having been imported into America from Europe where it is well but unfavorably known.

The grey-brown maggot or larva of this fly measuring from one-half to three-quarters of an inch in length eats its way into the interior of bulbs, killing the plants and finally leaving the bulbs before pupation in the soil.

The following bulbs are said to serve as food for this maggot: Narcissus, Amaryllis, Vollota, Habranthus, Eurycles, Saltonia and Scilla nutoris.

The best treatment now known is said to be immersion in water at a

temperature of 110° F. for three hours. Treatment should be made before growth starts and the bulbs should be subsequently dried.

Eustillus apicalis

On July 13, 1925, a very restricted infestation of this small beetle* occurred at Lowell, Michigan. These small beetles were found to be eating the roots from seed onions. It is interesting to note that Dr. S. H. Forbes reports serious injury to young seed corn by this beetle in Illinois in his report for 1905.

The Apple Maggot

(Rhagoletis pomonella)

In mid-August, 1925, a report of the presence of apple-maggot in destructive numbers was discovered at Stockbridge, Michigan where the infestation was found to be almost 100 per cent in some orchards. The recurrence of this pest came as a surprise since for twenty years or more, the applemaggott had failed to attract much attention. It was soon found however that the maggot was making itself felt, here and there, all over the state, very many growers having forgotten its habits and the appearance of its work. By the time that apple harvest was over it became evident that the creature was the cause of severe losses at widely separated points and as a consequence, circular bulletin No. 87, "The Apple-Maggot" was put out by this department to supply the necessary information concerning the recognition and control of this pest.

Cut-worms

The damage done by cut-worms during the spring of 1926 was more serious than usual. Besides the ordinary species that habitually cut off young plants at the ground level, there were many complaints of cut-worms that climbed up on the plants at night and devoured all sorts of garden truck. Mint fields in the vicinity of St. Johns suffered severely. The author of much of this trouble proved to belong to a climbing species, Euxoa messoria.

Fig. 18.-Climbing cut-worm, Euxoa Messoria, enlarged.

*Determined by Dr. M. H. Hatch, of Ann Arbor, Michigan. Determined by Mr. S. E. Crumb, Assoc. Entomologist of the U. S. Bureau of Entomology.