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Small trees are rarely attacked. In the localities visited, from one-half to two-thirds of the spruces with a basal diameter ranging from one to two feet were either dead or dying. Trees of this size are the most suitable for lumber and consequently the most valuable. The smallest affected tree noticed had an estimated basal diameter of about ten inches. In this case the attack appeared to be a failure, for so much resin had oozed from the wounds that the work was obstructed. The galleries were scattered and single and their authors were found dead, each in its furrow. No larvæ were present and the apparent attempt to establish a colony in this tree had thus far failed. But it may be that this tree had only been attacked for the purpose of obtaining food and had not yet been brought into that sickly, languishing condition thought by some entomologists to be necessary to induce the establishment of a colony, the deposition of eggs and the development of larvæ. For it is said of the Scolytus destructor, a bark-mining beetle that sometimes proves very destructive to elm trees in Europe, that the adult insects first attack healthy trees for the purpose of obtaining food and when by this means the vigor of the tree has become somewhat impaired the female deposits her eggs in her galleries. Then the rapidly increasing numbers soon destroy the life of the tree.

When two trees of unequal size stand in close proximity the larger one seems to be most liable to be attacked. In one instance two trees stood scarcely more than three feet apart. The larger one had been attacked, the smaller remained unharmed. In another similar instance the larger of the two trees was dead, having been attacked first, the other was dying. Why this preference on the part of these insects for the largest trees? It may be that young trees are apt to be too resinous to be attacked successfully. In the case of the small tree already mentioned the gummy exudations from the perforations in the bark first attracted my attention. Or the insects may instinctively know that a tree

with a large trunk presents a broader field for their operations than one with a small trunk; or possibly the vigor of the tree may be so impaired by age that it is more readily brought into suitable condition for the habitation of these parasites. Whatever the cause of this selection, no diseased condition of the trees was detected except that which was accompanied by and to all appearance was directly due to the insects themselves. Certainly if the tree is at all diseased before its attack the insects must be exceedingly quick to detect it, else they could not be found in abundance in trees whose leaves are yet green and whose sapwood is yet fresh and moist except where stained by their excavations.

In the vicinity of Lake Pleasant the affected trees are upon the mountain slopes or on dry ridges where the spruces are especially abundant. And we might naturally expect that the insects would be attracted to and carry on their depredations most extensively in those localities where the material on which they work is most abundant. In the valleys I saw no trees affected by them and yet they doubtless do carry on their destructive work in the low lands where spruces abound. I see no reason why they should not.

In some localities their ravages have already ceased. On the slopes of an elevation a few miles southwest from Speculator mountain there are two groves of dead spruces. Many trees in both were examined, and, though all the dead ones bore unmistakable marks of the former presence of the beetle, not one could now be found either in the adult or in the larval state. What had caused them to disappear? Surely not the lack of material on which to work, for several large living spruces yet remained. This leads to the consideration of remedies. Doubtless there are natural agencies whose free operation has a tendency to check the ravages of these insects and to prevent their excessive multiplication, but there are times and localities

in which these opposing agencies are inefficient or inoperative and then these destructive insects multiply rapidly and their ravages become painfully apparent. It is then necessary that man himself should do something to protect his property from these active little foes. It was noticeable that many of the dead trees in the two groves just mentioned had their bark so chipped by woodpeckers that the general hue of the trunk was a reddish brown instead of the usual grayish brown. Here then is a possible explanation of the cessation of the ravages and the absence of the insects. Here is doubtless the indication of one of nature's antidotes to the mischief. The woodpecker is the natural foe of such insects. With its long beak and barbed tongue it extracts them as a dainty morsel from beneath the bark. It is quite probable that these birds had congregated in these two localities in sufficient numbers to completely stop the ravages of the insects. of the insects. A few were seen at work on the affected spruces of Speculator mountain, and if not interrupted they will probably in due time succeed in checking the ravages there also. The protection of these birds is to be enumerated among the means to be employed in checking the malady of the spruces. They are the friends of the forest and the allies of man. cant the insect yet how capable of injury. How lightly we esteem the woodpecker yet how indispensable are his services.

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A remedy employed in similar cases in Europe is to cut down the affected trees, strip off their bark and burn it with its destructive tenants. Though it is somewhat doubtful if the owners of large tracts of timber land can be induced to adopt this method of checking the destruction of their spruces, it is certainly to be recommended. The loss from its omission would soon far exceed the cost of its employment, but care should be taken not to engage in this work in a dry time lest the destruction from forest fires should be greater than that from insects.

A brief extract from the Entomology of Kirby and Spence will show that the ravages of insects upon forest trees in Europe have sometimes been serious, and that it is none too soon for us to note well what is transpiring in our own forests.

"The bark-borer of the oak is a small beetle of an allied genus, Scolytus pygmæus, which with us does no great harm, but so abounded of late years in the Bois-de-Vincennes near Paris that 40,000 trees were killed by it; and many of the finest elms in St. James' Park and Kensington Gardens as well as in the promenades of various cities in the north of France, have fallen victims to another of this tribe, Scolytus destructor, whose trivial name well characterizes the frequency and severity of its ravages. The ravages of Tomicus typographus in the pine forests of Germany have long been known under the name Wurmtrokniss (decay caused by worms), and they sometimes attack the inner bark in such numbers, 80,000 being sometimes found in a single tree, that they are infinitely more noxious than those insects that bore into the wood. About the year 1668 this pest was particularly prevalent and caused incalculable mischief and in 1783 it is estimated that a million and a half of trees were destroyed by it in the Hartz forests alone. At this period, when arrived at their perfect state, they migrated in swarms like bees into Suabia and Franconia. At length between 1784 and 1789 in consequence of a succession of cold moist seasons the numbers of this scourge were sensibly diminished, but they appeared again in 1790 and so late as 1796 there was great reason to fear for the few fir trees that were left." Westwood states that occasionally the evil was so great that prayers were offered in the churches against its extension. While we hope that our spruce-tree bark-borer may never prove to be such a pest as this Tomicus we certainly think that he deserves some special attention.

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