This section is from the book "The Gardener's Monthly And Horticulturist V22", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
The following, from the annual address of the President of the Entomological Society of Ontarios from the Canadian Entomologist: The City of Ottawa being one of the great centres of our lumbering interest, it seems fitting that I should on this occasion call your particular attention to some of those insects most injurious to our pine forests. The losses occasioned by the destructive work of borers in pine trees both before and after they are cut are unfortunately too well known to those interested in the lumber trade, although the sufferers may not be familiar with the life histories of their enemies so as to be able to recognize them in the various stages of their existence. The lumberman suffers from the work of a number of destructive species, nearly all of which inflict their greatest injuries during the larval stage of their existence.
There are three families of beetles in which are included the greater number of our enemies in this department. I allude to the longicorns or long-horned beetles, Cerambycidse; the serri-corn or saw-horn beetles, Buprestidie, and the cylindrical bark beetles, Scolytidse. Togo over this long series in detail would weary you. A brief sketch of the life history of a single example in each family will serve as representatives of the whole.
One of the most destructive of the species included in the Cerambycidse is a large grey beetle with very long horns, known to entomologists under the name of Monohammus confusor, and popularly in this district as the "Ottawa Cow." "Where trees have become diseased from any cause, or where a fire has ravaged a pine forest, and scorched and partially destroyed the timber, or where logs after being cut have been allowed to remain a season in the woods or in the mill yard - there these insects gather and soon multiply to a prodigious extent. The mature insect is over an inch in length; the antenna of the male reaches the extraordinary length of from two to three inches, while_those of the female are shorter. The female lays her eggs in the crevices of the bark, where the larvae when hatched eat their way into the wood, burrowing extensive galleries through the solid timber; when mature they are large, white, almost cylindi-ical, footless grubs. They pass their chrysalis stage within their burrows, and the perfect insect on its escape eats its way out through the bark.
There are about a dozen species in this family known to be destructive to pine.
Most of the insects belonging to the family Buprestidse may be recognized by their brilliant metallic colors; they have very short antennae which are notched on one side like the teeth of a saw, and are often hidden from view by being borne under the thorax. Chalcophora liberta is one of the most destructive to pine trees, and its history is very similar to that of the long-horned beetle just described, but the larva is of a different form, and has the anterior segments or rings of the body very large, reminding one of the appearance of a tadpole. The perfect insect is about three-quarters of an inch long, of a brassy or coppery hue, with the thorax and wing-covers deeply furrowed by irregular longitudinal depressions. Dr. Fitch enumerates twelve species belonging to this family which are known to be injurious to pine. Additional information in reference to these beetles may be found in an article contained in the last annual report of our Society, by Mr. J. Fletcher, of Ottawa.
The cylindrical bark beetles, Scolytidee, are also a numerous family, eight species of which are known to attack pine. The boring Hylur-gus, Hylurgus terebrans, is probably one of the commonest. This beetle is about a quarter of an inch long, of a chestnut red color, thinly clothed with yellowish hairs, and is found during the month of May. The larva, which is a small yellowish white footless grub, bores winding passages in every direction in the inner layers of the bark of the tree, and also through the outer surface of the wood.
In some parts of our Province pines are greatly injured and sometimes killed by the attacks of a woolly bark louse, which covers parts of the trunk and branches with a white cottony secretion, under the protection of which myriads of tiny lice live, puncturing the bark with their sharp beaks and exhausting the trees by feeding upon the sap.
While we are mainly interested in the preservation of our mature forests, the future of our country demands that we shall not overlook the young growth on which the lumber supply fifty or a hundred years hence must largely depend, and which it should be the policy of our rulers to protect as far as possible. Most of the governments of Europe are now fully alive to the importance of this matter, and are annually spending large sums of money in establishing young forests. Two years ago I called your attention to an insect then recently discovered by Prof. A. R. Grote, of Buffalo, which was greatly injuring the terminal shoots of both the white and red pines in Western New York; it was the larva of a small moth, Nephopteryx Zimmer-mani, which fed under the bark, causing a free exudation of resinous matter from the wounds it made, followed usually by the death of the twigs infested. Since then it has been found over a much wider area than was at first anticipated, and I have no doubt but that it is to-day materially retarding the growth of young pine trees in many portions of our Province.
At the recent meeting of the Entomological Club of the American Association for the Advancement of Science (where our Society was represented by your President and Vice-President), Mr. S. H. Scudder, of Boston, submitted some observations on another lepidopterous insect which is injuring the young pines growing on the Island of Nantucket. It is a species of Retinia closely allied to Retinia duplana of Europe. The moth lays her eggs near the tips of the twigs, down which the young larvse burrow, killing them outright, and thus stunting and almost destroying the trees. Prof. Comstock, of Washington, also referred to two other species of Retinia which he had observed injuring the pine trees in that city.
In addition to all these there are a score or two of species of insects which are known to devour the leaves of the pines, damaging them in some instances very much. From the facts enumerated it is evident that we are suffering serious loss in all our lumbering districts from the silent workings of these insidious foes, and since in some measure to be forewarned is to be forearmed, I desire to call the special attention of those immediately concerned in the prosperity, present and future, of the lumbering interests of our country, to this important subject. Unfortunately it does not as yet seem to be within the power of man to do much directly towards restricting the operations of these enemies to our forests; yet this should not deter us from studying their habits and history, since an intimate acquaintance with these may result much more to our advantage than we now anticipate. A few trees, such as a belt, or a group planted for shelter or ornament, may be protected from the leaf and twig destroyers by syringing with a mixture of Paris Green and water in the proportion of a teaspoonful to a pail of water, and the bark lice may be killed by the use of alkaline washes applied with a brush or broom, and a timely application of the same will prevent the operations of the borers; but it is scarcely possible that such remedies can ever be applied over extended areas of forest.
It is, however, gratifying to know that in addition to the numbers devoured by our insectivorous birds, that almost every injurious species is in turn attacked to a greater or less extent by insect parasites of the most active habits, who seek out and destroy these pests with ceaseless diligence; were it not for these friendly insects the destructive species would be far more numerous individually than they now are.