Chapter X. 



INSECTS INJURIOUS TO THE ASH. 

 Fraxinus americana, etc. 



Although only about forty-six species are as yet known to prey 

 upon our native species of ash, the number is probably at least as great 

 as that given by Kalteubach asatiectiug theash in Europe, viz, fifty-one. 

 Thus far no species of dipterous gall flies or of Psyllids has been de- 

 tected on our native species. My own opportunities for observing this 

 tree have been limited, but during September, 1887, I was able to dis- 

 cover seven species new to the tree, living on young bushes on the 

 northern shore of Rangeley Lake, Maine. When used as ornamental 

 or shade trees the difterent species of ash appear to be in general quite 

 free from insect pests. 



Ash lumber does not seem, so far as we know, to be commonly attacked 

 by borers, the only case known to us being that ofUbiiriaquadrigeminata, 

 described below by Mr. McXeil. Ash w^ood is used for carriages, furni- 

 ture, as well as fence rails, and is a most valuable tree, besides being a 

 beautiful, clean, shade tree. 



AFFECTING THE TRUNK AND BRANCHES. 



1. The ash sesian. 

 Fatua denudata (Harris). 



The following account of the habits of this borer has been communi- 

 cated to me by Mr. W. L. Devereaux, of Clyde, K Y. : 



The Mgeria denudatuvi certainly does great injury; it is more abundant in some 

 swamps than others. It channels its cylindrical burrow from the tap-root di- 

 rectly up the trunk sometimes to a height of 3 or 4 feet, before turning and cut- 

 ting its way out. The perpendicular burrow is never situated in the center of the 

 tree, but is generally nearer the bark than the heart. The upright or vertical part of 

 the channel is as perfectly made as with a brace and bit. Through this initial inva- 

 sion, wood ants, members of the Rhyuchophora, Cerambycidse, Lamellicorns and Ser- 

 ricorns, obtain a foot-hold, and ere many years we have a hollow ash tree. Some of 

 the Capricorn larvse are channeling up the heart while certain Xylophagae are 

 boring into the same decaying sap-wood, and even into living healthy wood, until 

 the merest shell remains to support the still vigorous branches above. The Osmo- 

 dermas, Diaperidii, Tenebriouii, Elateridte, etc., follow on till the fatal storm-blast 

 gives them the whole remaining trunk and top for larder and shelter, lasting many 

 future broods. 

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