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Figure 2. The menace of the caterpillar.—Trees not sprayed.

See page 67.

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Figure 3. The menace of the caterpillar.–Result of spraying with arsenical poisons.

See page 67.

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figure 5, may very readily be seen where the foliage is off. Every young orchard should be examined early in the spring and, if found infested, should be thoroughly treated with caustic soda or some other strong alkali.

The eggs of this insect hatch in June, or early in July, and the little lice travel rapidly over the surface of the young wood and the fruit until they find a satisfactory feeding ground, when they insert their beaks and begin their campaign against the life of the tree. Figure 4 shows the young lice, natural size, early in July.

Spraying the trees thoroughly with kerosene emulsion when the lice are in the migratory stage, as described in “How to Fight Apple Enemies," has in every instance, at the Station, been effective in controlling this pest.

APPLE SCAB. Another ever present, and very generally neglected, pest of the orchard is the fungus disease, apple scab, or "black spot" as it is sometimes called. This disease, figure 8, has been so frequently described as to be perfectly familiar. As shown in former reports of this Station,* spraying is effective in securing a crop of fruit relatively free from this disease, even in those seasons when the scab is most prevalent.

For several years the conditions in most parts of Maine have been such that the fruit has been relatively free from scab, and as a result many growers who took up the practice of spraying some years ago, have gradually ceased to spray. It should be said, however, that this neglect is wholly comparable to the neglect which permits the lapse of a fire insurance policy. It may be unnecessary to spray to secure a crop of fair fruit one year, or even two or three years in succession; but when the unfavorabie season does come, if spraying has been neglected, there is frequently a needless loss of several hundred barrels of fruit in orchards of average size.

As a result of the studies above mentioned † the fact was clearly demonstrated that, in a bad season, there was a difference of 50 per cent in the amount of perfect fruit upon sprayed and unsprayed trees; the best results being obtained from the use

* Ann. Rpt. Maine Expt. Sta. 1891, 1892, 1893, 1894. See details and summary, Rpt. Maine Expt. Sta., 1893, 125-128.

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of Bordeaux mixture. In other words, trees not sprayed gave on three successive years 4.1, .9, and 38.2 per cent of the fruit free from scab; while the same years an equal number of trees sprayed with eau celeste (copper sulphate, carbonate of soda and ammonia) gave 57.8, 30. I and 72.8 per cent respectively. The third year Bordeaux mixture was used and gave still better results-79.9 per cent of the fruit being free from scab.

From these, and similar results obtained all over the country, it is evident that spraying has ceased to be an experiment as a means of controlling certain orchard diseases. The results above cited have been repeatedly confirmed both at this Station and elsewhere. Reference is made to the subject at this time only to emphasize the importance of using precautionary measures. Even though there be no crop of fruit, the increased vigor of the trees as a result of clean healthy foliage, will far more than repay the cost of spraying. This spraying with Bordeaux mixture should be done first before the buds burst, and again immediately after the blossoms fall, if but two treatments are to be given. If the season is very wet, however, at least four treatments at intervals of two or three weeks are found to be advantageous.

PINK ROT. In 1902 a comparatively new fungous disease made its appearance to a very destructive extent in western New York. This disease, known as "Pink Rot,” because of its pinkish, mildewlike appearance, had long been known to botanists but only, or mainly, as a saprophyte, or fungus which grows on dead or decaying matter. It did not come under the writer's personal observation until the present season; although said to have been destructive to stored apples in Maine in 1902.

The appearance of this trouble is well shown in figure 9, from a photograph of fameuse apples grown at the Station the past year. The best description of the trouble, with a full account of its life history, is given by Eustace in Bulletin 227 of the New York Agricultural Experiment Station.

The disease attacks the fruit on the scab spots, where it appears like a pinkish mildew. Later in the season, the spots become brown, sunken and rotten. If badly attacked the whole fruit soon decays. Because of its appearance only on the scab spots, many have regarded it as simply another form of the

apple scab. Others have referred to it as a parasite on the scab fungus. Eustace maintains, however, that "there is absolutely no connection between the two. The only part that the scab had in the matter was that it ruptured the epidermis (skin) of the apple, thus making an entrance for this fungus to grow into the tissue and cause the rot.”

A distinctive characteristic of this disease is that the decayed spots are rather dry and corky, and not very deep. Apples thus affected might, in some cases, be used for evaporating, as the diseased portion could be removed in paring; but because of the bitter character of the rot, affected fruit would be worthless for cider.

The disease is specially destructive to stored fruit, the sweating" of the fruit furnishing just the right conditions for its rapid development. Eustace reports that: “It was noticeable that the fruit in the bottom of large bins, such as are used about cider mills and drying houses, would become one mass of decay if allowed to remain there longer than a few days."* It was in stored fruit that the loss before mentioned occurred in Maine.

As is well known, the “scab" is ever with us, and growers have become accustomed to its disfiguring presence; but with the advent of this destructive secondary enemy, the importance of warding off the attack of both becomes imperative. Thorough spraying with Bordeaux mixture is the only safe means of preventing this trouble.

"*

EFFECT OF AN UNBALANCED RATION? In 1904 an obscure disease affected the fruit of certain trees in the orchard of Mr. Chas. S. Pope, Manchester. No similar trouble had ever come under the notice of the writer and this note is made simply as a matter of record. A careful study of the cause of the condition described is being carried on at the present time.

In August, when about the size of walnuts, the fruits began to crack and to drop. Marked indentations, somewhat similar to those made by curculio, were abundant. No evidence of insect work could be discovered, however. When the fruit was opened, the tissue under the indented parts was found to be dry

* Bul. 227, N. Y. Expt. Sta., 378.

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