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Show SAN JOSE SCALE IS PRIMARILY A PEST OF PEAR, PEACH AND OTHER FRUIT TREES Extremely Important That Grower Should Know Just Which Plants Are Most Likely to Be Attacked by Little Insect Some Serious Mistakes Made. (By F. BHEHMAN, JR.) Trees that are badly infested with the San Jose Scale appear as if they had been dusted over with ashes, if the branches and twigs where the Insects In-sects are numerous bo scraped with a knife it will be seen that this unnatural un-natural covering Is quite easily removed, re-moved, coming off in little flaky patches. Each of the little circular gTay objects is a separate scale, each covering a tiny yellow Insect underneath. under-neath. On thickly infested branches they often become so crowded that the scales are piled over one another bo that the real bark of the tree is not visible at all. Branches and twigs which are only slightly or moderately Infested will not be thus completely covered over, and the bark may be of Its ordinary color and appearance except here and there along the branches where the scattering scales are found. The largest full-grown scales are about the size of an average aver-age plnhead. They can, therefore, be detected by any person who has In the beginning an intelligent idea of the Insect, has sharp eyes, and who happens to look in the right place. Usually the farmer or fruitgrower k does not know that there is any ser ious trouble until the trees begin to die. By that time they are covered by the scales and present the ashy appearance. Then, If the owner finds that his trouble is San Jose scale, he Is apt to think that it is only on those trees that present the unnatural appearance, ap-pearance, when In reality It may already al-ready be on every tree In the orchard. Such a mistake often costs the lives of many trees, since the owner, Instead In-stead of examining closely and treating treat-ing every infested tree, as he should such a spot be found, however, It must then be examined to see if il is caused by a true scale-insect, foi there are certain unimportant diseases which may have a similar effect. II the little gray, circular scale is found In the center of the spot, and if the scale Is readily removed by scraping gently with a knife blade or the finger nail, then you may be prettj sure it Is San Jose scale, and should at once send specimens to your state entomologist and find out. Turn one of the scales over gently with the point of a knife. If it Is one of the large full-grown scales the insect may as likely be dead as alive under it, for the scale adheres long after the Insect is dead. If the insect is alive it will be seen as a little, yel low object, slightly egg shaped, but more pointed at one end, and slightly flattened. Indeed, It has been well described as resembling a tiny bit ol cheese or yellow butter. Press the body with the point of" the knife or pin and it is easily crushed, yielding a tiny bit of yellowish, oily liquid. If, on the other hand, the Insect is dead, the dried body will likely be found simply as a thin yellowish-brown particle par-ticle under the scale. The San Jose scale Is not capable of living and thriving on all kinds ol plants, and it is extremely important that the grower should know which ones are most liable to attack. It is primarily a pest of orchard trees and it is an exception, rather than the rule, to find It on any other. Of the orchard fruits, peaches, plums, apples, pears, and cherries seem to be worst attacked and die most readily in the order nomed. Certain varieties, especially es-pecially of pears, seem to show considerable con-siderable resistance, the Keiffer, Le-conte, Le-conte, and Garber seeming to be less attacked than others, though by no means exempt. Sour cherries are also resistant. Forest and shade trees are very seldom "infested with the San Jose in harboring or spreading Infection. Growers sometimes make serious and ridiculous mistakes on this point and give up hope because they imagine that the "scale is in the woods," or they try to destroy the forests which they suspect, or spend hours in a fruitless search for it on the forest or shade trees, and then, when they find a scale (which is some other species in nine cases out of ten) they think that they have surely found it. ; Let us repeat, then, with greater emphasis, that: the San Jose scale is primarily a pest of orchard fruit trees; it may also occur, but less frequently, fre-quently, on rose, grape, currant, gooseberry, goose-berry, mockorange, and Japan walnut, but forest and shade trees are not appreciable factors in harboring or spreading it. THE SAN JOSE SCALE. Infested twig to right; immature acales In center; full grown female scale above; Infested pear fruit to left showing reddish blotches. do, simply takes out those which are already in dying condition, and then, because he sees no more of similar appearance, he imagines he has exterminated ex-terminated it, when as a matter of fact other trees moderately or slightly slight-ly infested still stand ln the orchard and soon begin to die, having in the meantime spread the insect into still other trees, and so on, until the whole orchard may be ruined. Where the scales are not numerous enough to crowd one another each individual in-dividual grows to somewhat larger size than when they are crowded. JWhere the scales are scattering along the branches each scale is often (but not always) in the center of a slightly reddened spot on the bark. If the patural color of the bark be reddish this will not show plainly, but if the bark be of a light green or yellow, the reddish spots are quite conspicuous. conspic-uous. In looking for scale on slightly Infested trees it may usually be more readily found by looking for these reddish spots than by looking for the scale itself, but close watch must be kept for both scales and blotches. If |