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ble life is, in many respects, partially, if not wholly, subject to conditions which affect the physical system, it is assumed that the velocity of the prevailing winter winds which pass over the large extent of treeless plains of the northwest must be very great, and that the extraction of heat and exhalation of moisture from exposed vegetation, must be in porportion to the degree of cold, the velocity of the wind, and the length of time during which these adverse conditions prevail. The effect of these influences upon trees that have made so late a growth in autumn as to leave imperfect cellular formation in the whole or any portion of the tree, in combination with either a very dry or wet soil, may be partially manifested in the disintegration of the imperfectly formed cells of the roots, or in the bursting of the bark at or near the collar, or in the rupture of the inner bark and wood-cells of portions of the stems, and at the junction of branches with the bodies of the trees; or the injury may be confined to the extremity of the branches, or in extreme cases, when subjected to many or all of the conditions adverse to the sustenance of vegetable life, the tree may be injured in every part of its organization.
Now as the longevity of fruit-trees is dependent upon the peculiarities of their constitutional organizations, and upon the climatic conditions to which they are subjected; and as these conditions are violent extremes of cold and heat, dependent upon the velocity and direction of the wind; and as the coldest and strongest prevailing winter winds are from the west and north-west, and the thermometer ranges the lowest at the time or soon after the wind is from that direction, and highest when from a southerly direction; and as the degree of extraction of heat, and the volume of exhalation of moisture are greatest when the winter winds are in the northwest; and as these dependent forces result in injury to vegetable growth and life, it is clearly deducable, that strong winter winds are one of the principal causes of injury, and that, if by any means orchards can be so protected as to break or impair their force, the injuries manifested in orchards will be lessened in like proportion. If this be true, tender varieties planted and tested in orchards which are located in the heavy timber lands, some of which have the original forest growth so located as to break the force of the wind upon one or more sides of the orchard, may be expected to afford examples tending to substantiate the conclusions herein de
duced. The majority, if not all the intelligent horticulturists of the State concede that many varieties of apple trees are more hardy and productive in the heavy timber counties bordering upon the western shore of Lake Michigan, than the same varieties grown in the oak openings or in prairie sections.
The productiveness of tender, as well as hardy varieties, in the lake shore timber counties, may be partially attributable to the influence which so large a body of water as Lake Michigan must necessarily exert upon the atmospheric currents in the summer months. But this influence is not as considerable as might be presumed, from the fact that the prevailing summer wind is southwest. The lower air current, therefore, being towards the lake instead of from it, is only modified so far as the upper air current, moving in an opposite direction, may, in its course, ultimately join the whole or a portion of its constituents and forces with the lower air current. In the winter months the prevailing winds are from the northwest, and when the winds are from the lake to the land, the mercury might be expected to range lower at lake shore stations, than at stations further inland, in case there are no modifying upper air currents, and no forests to obstruct the force of the wind. But suppose it to be conceded that when the wind is northwest the mercury is not as low as at inland stations, it is assumed that when the wind is from the lake to the land, the water of the lake being warmer than the air current modifies the degree of cold, and as the air current progresses inland, the temperature is gradually lessened so that the actual extremes resulting from a westerly or northwest wind, and an easterly one, are greater than in the inland counties, and that the injuries resulting to fruit-trees, from the greater extremes of temperature in the lake shore counties would be greater than in the inland counties, were not the winter extremes of cold, existing when the wind is northwest, modified by natural forests.
Neither can the supposed or real differences which exist between the hardiness of orchards in the timber and prairie counties be attributed entirely to different constituents contained in soils, from the fact that the soils in the timber counties are so variable, that the plant-food ingredients contained in the various gradations of clay, sand, gravel and loam, are to be found in almost every orchard of considerable size, the soil constituents of which are wholly or partially represented in soils contained in orchards in the prairie
counties. In all the timber counties that have come under my observation, the healthiest and most productive orchards, are those that have the original forest growth, located upon the north or west side or both. As a further evidence of the benefits derived from orchard protection may be cited the facts, that in the early settlement of Milwaukee county, the whole country extending from the lake to the prairie was a dense forest, with occasionally a clearing of from two to ten acres; at this time peach trees were planted which came into bearing, and produced so abundantly as to break down many of the trees, while others perished from exhaustion, caused by over-bearing. Since that time, the land has been denuded of timber to such an extent, that peach trees can not be grown, except in isolated localities favored with some sort of protection.
Having determined some of the causes that have tended to cause injuries to fruit-trees; and having adverted to the laudable efforts which have been, and are now being made for the introduction of iron-clads, originating hybrids, acclimating varieties by reproduction from seed, and winter mulching for the purpose of prevention; and, having cited facts indicating that natural forest protection is beneficial, it remains to be seen, what further efforts are necessary to assist and forward the steps already taken for the accomplishment of the desired results, in the shortest possible space of timé.
As already shown, the winter winds are one of the prime causes contributing to produce disastrous results. Hence orchardists should consider it of the utmost importance to plant belts of trees around their orchards; the trees to be planted at such distance apart that the subsequent growth may, within a reasonable period of time, be sufficiently compact, to break or impair the force of winds; and also to plant dense lines of trees in the orchard, at distances of not to exceed one hundred and eighty feet. Evergreen trees are the best adapted for orchard-belts and protection lines, from the fact that they retain their foliage; each leaf of the compact foliage tending to obstruct and break the force of the strongest winds, and thereby lessening the extraction of heat, and the exhalation of moisture.
One row of evergeens closely planted will not only cost less money, and occupy less surface of ground, and require the expend
iture of less labor in planting, but will prove more efficacious for the purpose intended, than ten rows of deciduous trees, which have only their naked stems and branches to obstruct the force of the wind. Individual efforts in planting evergreen timber belts for orchard protection will not only prove efficacious for the purpose intended, but will be found to be practical and effective in producing early satisfactory results from the fact that the results will enure to the benefit of the individual planter, and are not subject to the delay incident to the passage and enforcement of statutory enactments, or want of concert of action, when dependent upon public effort.
The attention of orchardists being called to the necessity of planting evergreen tree belts for the purpose of preserving the vitality of fruit trees, preventing the fruits being blown off the trees, beautifying the landscape and enhancing the value of real estate, fruit-growers should not hesitate to adopt the principle that the planting of an evergreen timber belt is just as necessary a requisite as the planting of the orchard itself. Orchard protection is not only beneficial, but is also entirely practical, from the fact that small evergreen seedlings suitable for timber belts, and for forest tree planting, are now grown from seed in America, as in Europe, by the millions, and can be purchased at so small an out-lay of money, that the entire expense need not exceed the cost and labor of planting the fruit trees contained in the orchard.
There is great difficulty in preventing this insect from spoiling a large share of our apples. Want of co-operation in neighborhoods prevents success in the case of individuals who are using the best known means for its destruction. If all, both in villages and in the country, would try, much might be done with the remedies now known to lessen the ravages of this insect. What are these remedies?
First, destroy the larva as far as possible. The larval period of
the first brood is very short, only some three or four weeks in the forepart of summer, but that of the second brood must be fully eight months; from late in August until the next May. Eight years ago last September, I placed some choice early apples in a closet where I kept my best clothing; during the winter, I found under my vest collar the larva of the codling moth, plump and active; leaving it undisturbed, I carried it to the Northern Illinois Horticultural Convention, in February. They can be found just as plump and active about the hoops and head linings of apple barrels taken from the cellar in April. During the winter they remain in their nest, not a proper cocoon but selecting a position where they can just enter, they close up the sides all around them and there remain until time for them in the spring to form their cocoon, in which, in a few days, the larva or worm is transformed into a moth, a slim, gray miller, which, when the apples are very small, flies at night and deposits one egg in an apple. Well informed entomologists think that each female is capable of laying about 150 eggs; consequently a pair of moths will destroy about that number of apples. As they are double brooded-first brood working in the young apples in June, the second brood in August and September-those not destroyed by man, animals, birds, and parasites are capable of spoiling much fruit.
During the month of March following, after the severe cold weather is past, we would recommend scraping the rough bark carefully from the bodies of the trees. We may see some of the worms and kill them. Those which drop on the ground will be too torpid to crawl up, and we think would be killed by storms and freezing. In scraping off the bark, use a transplanting or plastering trowel, and try to avoid injuring the live bark. A hoe is too rough, unless very carefully used.
As another preventive we should sort our apples very carefully in the fall, and put as few wormy ones in our cellars as possible. Where apples are kept in barrels or boxes in the cellar, the appleworm is often seen under the tops or head-linings, or crevices, where they can crawl in and find a dry place. We have found them under the head-linings on the bottom of the barrel. If they can get out of the cellar, they will enter the rooms above and conceal themselves about clothing. These boxes and barrels should be taken out of the cellar in April, and carefully examined and the