Rensselaer Semi-Weekly Republican, Volume 19, Number 13, Rensselaer, Jasper County, 19 October 1897 — The San Jose Scale in Indiana. [ARTICLE]

The San Jose Scale in Indiana.

Newspaper Bulletin, Purdue University Experiment Station. i The San Jose Scale, about which so much has been said of late, is pre-eminently a fruit insect, as it feeds upon all kinds of fruit trees, and as such it is more to be feared than any other fruit pest yet introduced. It has only been about eleven years since it was brought from California on nursery stock to New Jersey, and yet within that time it has spread to more than twenty different States. It has probably been in some sections of Indiana since about 1890. I have been unable to find it on trees which were planted previous to that time. My attention was first called to it last winter by Mr. J. E. Reyman, of Salem, Washington county, who sent me some infected plum branches. This tree was dug up and destroyed, but on visiting his place

last June, I found that it had spread to adjoining trees. Since that time I have found it near Borden, Bardie and Henryville. Clay county, Madison, Jefferson county, Indianapolis, Marion county; and Peru, Miami county. In many places the orchards were found to be very badly infested; some have already been cut down and burned and others will doubtless soon follow, causing much disappointment and loss to the owners. HOW IT MAY BE RECOGNIZED. In looking for this insect most persons will pass it by unnoticed on account of its very small size. The female scale is only about l-25th of an inch in diameter, while the male is only about one half that size. The shape of the female is nearly circular, while the mgle is more elongated. The female is sharply convex or conical in the centre. This last character will help to distinguish it from many of the more common species. Its color is nearly like the bark on which it is found. Another distinguishing character is found in the reddish discoloration of the bark, immediately surrounding the scale, extending through both the outer and inner bark. These characters will enable one with an ordinary pocket magnifying glass to readily detect the presence of the insect.

TREATMENT. There are two principal remedies which are in use, (1) The hydrocyanic acid gas remedy, and (2) spraying with certain solutions or washes. The first method is not; in use to any extent except in California, and in fumigating nursery stock. The most practical remedy in the orchard is spraying the trees with a strong solution of whale oil soap, (two pounds dissolved in one gallon of water), or with a strong kerosene emulsion, or even pure kerosene oil when the leaves are off. The spraying should be done at two or three different timbs during the year. Quite recently Professor Rolfs of the Florida Experiment Station has discovered a fungous disease, similar to the chinch bug disease, working on this scale in Florida. It may be that this is Nature's remedy; if so it will doubtless come to our relief in , time. Should any person suspect the occurrence of this pest on trees in his neighborhood, the Station would appreciate receiving samples of the affected wood. James Throop, i ' Horticulturist.