Word: leopards
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Dates: during 1910-1919
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...preserve those trees which are still alive. A number of them were trimmed during the summer and the deadwood is now being removed from the remaining trees. The dead trees and decayed wood was found to afford breeding places for such pests as the bark beetle and the leopard moth and so the utmost care has been exercised in removing as much of this as possible...
...poor condition of the elm trees in and about the Yard has made radical changes necessary. The trees have been attacked by the leopard moth, which bores into the wood, making any attempt at their extermination practically impossible. Moreover, work on the subway and the sewerage system in Harvard square has been injurious to the trees, as much moisture is drained off, thus making them more susceptible to the attack of the moths...
While cutting the leopard moth larvae from the limbs of the elms last fall, a small beetle was found, which has since been identified as the European elm bark-borer--scolytus multistriatus-marsh. In Germany it is known as the "splint kafer" and it is one of their most injurious pests. It enters the bark and the newly hatched larvae work in the splint of the live wood causing the bark to loosen and eventually fall off. Scores of trees in the Yard and about Cambridge have been examined and without exception all of them are infected...
Insecticides fail to reach either the leopard moth or bark-borer. And such a spraying as the trees got when attacked by the elm-leaf beetle may have something to do with the apparent absence of insect enemies of the two above-named species. For the spraying of the trees could have easily killed their parasites, which might have been lurking about on the trees at the time the spray- ing was done. And one thing that favors this theory is,--the leopard moth is worst in that part of the Yard which was the most carefully sprayed...
...work of determining the life histories of these insects is being carried on as speedily as conditions will permit. Plans are also being made to put out trap trees and electric light traps in the spring. Further it is hoped that parasites of the leopard moth can be procured from Europe. And it has already been tried and so far has resulted in failure, because the larvae are very hard to find during the winter...