CONTENTS. 



Page. 



Outline of trip... ... .. 



The Androscoggin region and its spruce forests 



Dead and dying spruce 



Some characteristics of the dying and dead spruce 



Causes of decay and death 



Relation of insects to the trouble.. .. 



The spruce-destroying beetle 



Description of the destroyer 



Life history of the beetle - - 



How it passes the fall, winter, and spring . _ 



When activity commences in the spring, 



The summer period . . _ 



Summary of life history 



Explanation of diagram. 



Special features of the beetle's work 



Kind of trees attacked ; 



How and when the attack is made ... 



Its work in and beneath the bark ... ...... 



The distinctive, visible evidences of the spruce destroyers work. 



Pitch tubes. . 



Appearance of the leaves 



Appearance of the twigs 



Appearance of the bark and wood 



Woodpecker work «._...-. 



A common fungus on the bark of dead trees 



The principal natural enemies of the spruce-destroying beetle . 



A parasitic enemy 



A predaceous beetle ... 



Birds as enemies of the beetle . . 



A fungous disease of the beetle. _ - . 



Climatic conditions 



The principal insect allies of the spruce destroyer .. 



The spruce Polygraphus 



The spruce Tetropium 



Other insects . 



Historical references. ■ 



Remedies and methods of prevention 



Review of proposed methods - 



Stripping off and burning the bark 



Destruction of dead trees 



Girdling trees . 



Investigation of the girdled- tree method. 



Hack-girdled and peeled spruce . 



Report on girdling experiments, by Mr. Austin Cary 



Comments on Mr. Cary's work 



Suggestions and recommendations 



Methods of reducing the number of beetles 



Utilization of dead spruce 



Importance of harvesting the matured crop of spruce 



Summary .... 



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