THE SAN JOSE SCALE. 113 



THE SAN JOSE SCALE, A NEW INSECT FATAL TO 

 FRUIT TREES. 



PROF. OTTO LUGGER, ST. AXTHOMY PARK. 



This insect is as much to be dreaded, almost, as the grasshopper, 

 certainly more to be dreaded than the chinch bug, and you know 

 ■what that scourge means to Minnesota. It is known as the San Jose 

 scale, a deadly foe to all manner of fruit trees, and if it were intro- 

 duced into this state the extent of the damage cannot well be esti- 

 mated, for, though very tiny as an individual, taken in the aggregate 

 it becomes a vast devastating power. 



Fifteen states have already'' taken legislative action looking to an 

 eradication or a prevention of the pest. It is almost impossible to 

 prevent its spread when once it has gained a foothold. It was first 

 found in California, whence it takes it name of San Jose. It was 

 carried in fruit or on shrubs of some kind to New Jersey, where it 

 has already done much harm. It was not known in California until 

 about eight years ago, and no one knows where it came from be- 

 fore it reached that land of fruits. 



This scale is not a fungus growth but a live animal, male and 

 female, capable of vast reproduction, and one scale may be a daugh- 

 ter, a mother, a grandmother and a great grandmother in one season. 

 It derives its name scale from its appearance, a tiny particle not more 

 than an eighth or, generall}', not more than a sixteenth of an inch 

 in diameter, and shaped with a crest or covering which makes it 

 look like a scale. Soinetimes they are a dull gray in color, some- 

 times darker in hue. They have a very business-like way of going 

 about things, and when they have finished up a tree there isn't inuch 

 left but the skeleton. 



They maybe carried from one tree to another bj'^ birds, who get 

 the young and active insects on their feet or legs or on their bills- 

 Sometimes they are carried by ants, and if the trees are close to- 

 gether they will pass from one to the other of their own accord. 

 The scale saps the life of the tree, completely destroying it and 

 rendering it unfit for anything but the brush pile. It has a jointed 

 beak which passes down into the wood and takes up the sap. 



Not only do they infest the trunks and branches of the trees, but 

 thej'' are found on the leaves and fruit as well. When thej^ are 

 abundant on the fruit, it is destroyed or rendered worthless, though 

 the fruit appears sometimes with only a purple discoloration around 

 a single scale. They do not usually begin active operations until 

 early in June, and they pass the winter in a practically dormant 

 condition. Apple, pear, plum and cherry trees are the quickest to 

 be attacked, but other fruit trees, currants, gooseberries and rose 

 bushes are sought for when the supply of fruit trees gives out. 



There are various insecticides recommended, but so destructive is 

 the pest, the best way of getting along with them is not to have 

 them at all. To this end we should have a law, and one is alread}' 

 prepared and is now in the legislature for consideration, providing 

 that no nursery stock afflicted with the San Jose scale shall be 



