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tree at an early stage of its growth, which checks any tendency to over-luxuriance afterwards ; and to turn the powers of the tree to the formation of Hower-buds, and consequent production of fruit. Wall-trees are exposed to a higher temperature and greater evaporation than standards, and require, therefore, a larger body of soil and a more copious supply of moisture for their roots than standards do.

“ Having thus stated his views concerning the proper formation of borders, Mr. Drummond proceeds to notice some other circumstances to be attended to in their subsequent management: and this portion of his memoir is also illustrated by experiment.

“ When the borders have been properly prepared, success in the cultivation of wall-fruit trees depends more, says our author, on a judicious supply of moisture to their roots, than on any other part of the practice. The necessity of moisture to the due preparation of the food of plants, and to its entrance into the vegetable system, is well known; but if the soil get beyond a certain state of dryness, these necessary operations cannot proceed, and little or no nutriment can be afforded, at the very time, perhaps, when it is required most to assist in the production of fine fruit. The roots also, unable to find nutriment in a good soil, may penetrate into a bad one, and from thence derive matter not only not nutritive, but perhaps pernicious to the vegetating process.

“ In supplying water, Mr. Drummond recommends that it be taken from a pond in which it has been freely exposed to the sun. If the pond be not more than 3 or 4 feet deep, the temperature of its water will not differ much, during the summer months, from that of the soil of a border of similar depth. In such circumstances, watering will rather augment than diminish the temperature of the soil ; and will in no degree check the chemical changes by which the food is prepared in the soil, or impede the functions of the living organs destined to absorb it. Water from springs and wells, by reason of its coldness, considerably reduces the temperature of the soil, and ought not to be employed till its temperature has been raised nearly to that of the soil.

" To ascertain the effects respectively produced by spring and pond water of different temperatures, Mr. Drummond, in the year 1826, made the following experiments: – he selected four peach trees of the same species (grosse mignonne), which grew against a wall. Two of these trees were supplied during the summer with water taken from the spring, and the other two with water from the pond. In the border where the trees grew, and which was 12 ft. wide, two thermometers were plunged into the soil to the depth of 18 in., and its temperature carefully noted at the two stations before the water was applied; and also on the next day, or twenty-four hours after the application of the water. The temperature, too, of each kind of water was duly observed. These observations being previously made, the border was watered three times during the summer; and each time as much water was given as would have formed about a cubic foot of water over the whole surface. The author has exhibited, in a tabular form, the times when the experiments were made, the temperature of the soil, the kind of water, and its temperature when used; the temperature of the border twenty-four hours after, and the amount of heat gained or lost by the kind of water employed.

“ The first experiment was made on the 10th of May. At the depth of 18 in. the temperature of the border was 64°, and that of the spring water used 46°. In twenty-four hours after, the temperature of the border was reduced to 52°, or had lost 12°. At the same time the temperature of the soil being 64° as above, and heat of the pond water 67°, the soil at the close of twenty-four hours was 66°, or, instead of losing 12°, had gained 2°.

June 20th, the second watering was given. The temperature of the border at the depth of 18 in. was now 74°, and that of the spring water 52o. In twenty-four hours the border was reduced to 58°, or had lost 16o. At the station where the pond water was used the temperature of the border at the

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above-mentioned depth was 77°, and that of the water 82°. In twenty-four hours the temperature of the border was 80°, or had gained 3°.

“ The third and last watering was performed on the 28th of July. The temperature of the border at 18 in. below the surface was 72°, and that of the spring water 57°. In twenty-four hours the border was reduced to 61°, or had lost 11° of temperature. At the pond water station, the border at the depth of 18 in. was 78°, and the water itself 74°. In twenty-four hours the temperature of the border was still 78°, or had suffered no change of temperature from the watering it had undergone.

“ It is very clear from these facts, that, whilst spring water greatly cooled the soil, that from the pond exerted no such operation, but on the contrary often raised its temperature.

“ In proceeding to describe the effects on vegetation produced by these different kinds of water, Mr. Drummond observes that on the 10th of May, when the border was first watered, there was no perceptible difference in the appearance of the four trees : they had all excellent crops of fruit. About the first of August, however the contrast was very striking. No one would then have supposed that the four trees were of the same variety. The fruit of the two trees which had been supplied with the pond water was much larger, of a higher colour, and finer quality, than the fruit of the other two trees which had been supplied with spring water. The leaves, also, of the former trees were almost double the size of those of the latter. Even in the following spring the difference was perceptible, as evinced in the larger blossom and more vigorous setting of the fruit.

“In the management of borders, it is of great importance, continues Mr. Drummond, to preserve the surface roots of trees. At the cottage garden the borders have never been dug since the trees were planted; and, when manure is applied, it is laid down and covered over with about 6 in. of the surface mould. The soil, when thus treated, becomes filled to the surface with fibrous roots, which would be injured or destroyed were the border to be dug. When the manure is retained in a body near the surface the border is kept in a moister state, and the roots do not penetrate downwards to the subsoil in search of water. Even where vegetables are raised as early crops on the border, the soil is never disturbed to more than 6 in. in depth ; and the crops are ready earlier than in the ordinary mode of digging to the depth of 18 in. When the fibrous roots of trees have been injured by digging the border too deep, they will soon be restored if a layer of manure, 6 or 8 inches thick, be first laid on the surface, and then beaten down with the spade, and covered afterwards with about 6 in, of mould. The roots will at once begin to strike out and run along the under surface of the dung, forming at length a complete mass of fibrous roots.

“When vegetables are raised on fruit-borders, they may affect the atmosphere, in regard both to heat and moisture, in a degree that may sometimes prove beneficial, and at others injurious, to the trees. When the wall, for example, becomes heated, the air in contact with it is rarefied and carried upwards, and fresh air from the surface of the border moves forward to supply its place; in this way a current of air is soon formed, which continually passes over the heated wall as long as it retains an excess of heat. Of this circumstance advantage may be sometimes taken where the heat of the wall is excessive; for, by keeping the surface of the border in a moist state, we diminish at once the temperature, and augment the moisture of the atmosphere which envelopes the tree. On the other hand, by raking the border, as will afterwards be shown, we contribute to keep its surface in a dry state ; and thereby to increase the temperature, and lessen the moisture of the surrounding atmosphere. At different seasons these opposite practices may be beneficially adopted. Thus in spring, when the trees are in blossom, should a clear frosty night set in, with the prospect of bright sunshine during the next day, it is of no little importance to water the surface of the border before the sun appears, as the evaporation that succeeds will moderate the excess of heat which might otherwise prove fatal to the blossom. On the other hand, when the fruit is swelling it is of equal importance to keep the surface of the border dry, as the temperature both of the soil and atmosphere is then in-, creased, which contributes much to improve the size and quality of the fruit.

When, however, the borders are so thickly covered with vegetables as almost to prevent the access of the solar rays to their surface, such covering will contribute much to lower the temperature of the soil, and of the atmosphere in contact with the wall. To ascertain the extent to which this might take place, the author made the following experiments on a border covered with a strong crop of cauliflower, which completely shaded the surface. He took a therinometer and inserted its naked bulb about half an inch into the soil of the border, where it was covered with the vegetables. A second thermometer was laid on the surface of the border ; and a third was placed in close contact with the wall. A similar arrangement was, at the same time, made with three other thermometers in another part of the border, which was uncropped, and fully exposed to the sun's rays. The border itself was 12 ft. wide, and the wall of about the same height in feet. On the 10th of May, 1829, the author made four observations of these six thermometers, between 5 o'clock of that day, and 4 o'clock of the next, viz. at 5 a. M., i P. M., and at 10 P. M. of the iOth.; and at 4 A. M. of the 11th. The results of these observations he has given in a tabular form, of which a copy hibited.

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“ From this table it will be seen that at 1 o'clock P. M. the close crop of cauliflowers occasioned a reduction of 18° of temperature on the wall, as compared with that of the wall of the naked border: at 10 o'clock in the evening the difference of temperature between the two portions of wall was 8°; and even at 4 o'clock on the next morning the difference was 5o. On the 29th of May the cropped border was 4° lower than the naked one, at the depth of 12 in. beneath the surface.

“This effect of cropping, in lowering the temperature of the atmosphere, will, however, be much less when the sunshine is little and partial through the day ; and when the day is wet it will not be observed. The colour, too, of the soil will influence the result, a dark soil becoming much hotter than a lightcoloured one, when exposed in the same manner to the solar rays.

“ Vegetables in borders are least injurious to wall trees when they are planted in rows at right angles to the wall, and at double the distance usually

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allotted ; they do not then so completely shade the soil, and the air is permitted to flow freely though the rows. It will, however, be proper to have them cleared away (when planted opposite to peach and apricot trees) about the middle of July, that the borders may have the full benefit of the sun's rays, to enable them to ripen the fruit and mature the young wood. After a wet night the borders should also be raked, to aid the drying of their surface. This simple operation will increase the temperature of the surface of the border, and of the wall, many degrees. On one occasion, after two days of continued rain in July, 1829, the temperature of the surfaces of the border and wall was the same as that of the atmosphere, viz. 52°, at 4 o'clock in the morning. At 6 o'clock, the weather cleared up, and a considerable extent of the border, opposite to a hot wall, was raked, so as to dry the surface. At 1 o'clock, a thermometer, laid on this raked surface, indicated 118°; and another, applied to the wall opposite, 106°; whilst, on the unraked surface of the soil, the temperature was only 86°, and on the corresponding portion of the wall 899. The operation, therefore, of raking the surface of the border, raised its temperature 32° above the unraked surface, and the temperature of the corresponding part of the wall 17o.

“ The London medal, for 1833, placed at the disposal of the Caledonian Horticultural Society, was voted to Mr. Gregor Drummond for the communication, of which a copious and correct abstract is here given.” 10. Description of several new Varieties of Fruit raised ly Thomas Andrew

Knight, Esq., from Seed ; together with Notes thereon by Mr. Knight. The

pears described are March bergamot, Pengethley, Ross, Oakley Park bergamot, Brougham (a sample having been sent by Mr. Knight to Lord Brougham, and approved of by His Lordship), Bringewood, Moccas, Broom Park, Croft Castle, Eyewood, Dunmore, and Monarch. All these pears were raised by Mr. Knight; but their merits are not yet sufficiently proved to warrant our recommending them without the special sanction of Mr. Thompson, who, if we have failed to do justice to any of these varieties, will, we trust, be good enough to correct us. Mr. Knight also describes the Dunmore plum, raised by him, and also a party-coloured grape, not unlike the white muscadine in flavour, which “has in every season ripened tolerably well in the cold climate" of Downton ; and of which Mr. Knight says, “ I believe it to be better adapted to make wine in a cold climate than any cultivated. I feel confident that it is superior to most of the grapes cultivated in France, and that the merits of the French wines depend greatly more on the skill of the makers, than upon the merits of their grapes.” 11. Nole upon Mimulus cardinalis ; a new hardy herbaceous Plant. By John

Lindley, Ph.D., F.R.S., &c. Read November 4. 1835. This very showy and very hardy perennial, rare at the time this article was written, is already, thanks to the diffusive spirit which enters into every thing, now as common in gardens as columbine or sweetwilliam. 12. Meteorological Journal, 8c., for the Year 1835. By Mr. Thompson. 13. A Note upon Oncidium Lanceànum; a new Species of Orchideous Epiphyte.

By John Lindley, Ph. D., F.R.S. &c. A well-known epiphyte, introduced in 1834 by J. H. Lance, Esq., and named in compliment to him. 14. On Two Species of Insects which are found injurious to the Pear Tree. By

Thomas Andrew Knight, Esq., F.R.S., Pres. Read April 19, 1836. “The leaves of pear trees which are trained to walls have sustained, during some years, much injury in many gardens, from the depredation of the larvæ of a very minute species of moth, the Tinea Clerckella of Linnæus : and I

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have been informed that it abounded in the Royal Gardens at Kew in the last

The moth appears in the end of May and the beginning of June; and it is readily distinguished by the silvery whiteness of its wings, which are tipped lightly with brown, and by its small size, its length scarcely exceeding a single line. It is an extremely pretty little insect, and possesses so much activity, that it is difficult to obtain a living specimen of it. It probably deposits its eggs, or, perhaps, more properly, its spawn, upon the under surfaces of the leaves; and the larvæ, having there penetrated through the epidermis, feed upon the internal parenchymatous matter of the leaf. Brown and lifeless circular spots in consequence appear upon the leaves, such as an excess of heat would occasion ; and I have known several gardeners who have supposed it to be caused by solar action. These lifeless spots enclose the larvæ of the moth above mentioned, which do not exceed a line in length. Whenever the leaves of a pear tree contain many of these, the fruit does not acquire nearly its natural size, and it ripens without acquiring either sweetness or flavour.

“This insect is an old inhabitant of our gardens : I first observed it half a century ago, but it appears latterly to have become much more abundant. It greatly prefers some varieties of pears to others; the chaumontel appears, amongst the varieties in my garden, its favourite, and the glout morceau that which it likes least. The moth is, I believe, but little known; for Mr. Curtis, who was so kind as to give me the name of it, did not possess a specimen till he received one from me. My pear trees had sustained, during many successive years, so much injury from the depredation of this insect, and their fruit had in consequence become so defective in freshness and flavour, that I resolved to uproot the whole of them, if I failed to succeed in destroying or driving away the insects : but in the last summer I had the good fortune to obtain perfect success in driving them away, by the means which I proceed to describe.

“ Early in the spring of the year, when the blossom buds of my pear trees were about the size of large peas, water, which held in suspension a mixture of lime and flower of sulphur and soot, in about equal portions, was thrown by an engine over the pear trees and the surface of the wall to which they were trained. I applied this mixture because I had observed, as I have stated in a former communication, that it had apparently prevented the appearance of blistered leaves upon my peach and nectarine trees, though by what mode of operation I was then, as I still am, wholly at a loss to conjecture: but since the first application of it, I have not seen a single blistered leaf upon any tree to which it was applied. I, of course, distinguish blistered leaves from such as have been made to contract by the bite of the aphis.

“ The moths appeared as abundant as in the preceding year; and I then caused my trees to be washed once in every week during a month, after I witnessed the first appearance of the moth, with a weak infusion of tobacco in water : this mode of treatment proved successful, and the foliage of my pear trees, and some plum trees contiguous, escaped all injury. The moths were, however, only driven away; for the leaves of two pear trees which grew at some distance were almost wholly destroyed, and the foliage of the medlar and cherry trees in the vicinity sustained a good deal of injury from them. Nearly all the leaves which contained any of the larvæ were collected and burned, and comparatively very few of the larvæ escaped; and I do not at all doubt but that, by adopting the saine measures next year, I shall succeed in securing my pears from future injury.

“ There is another species of insect which frequently injures the pear tree, whose depredations are less visible, and consequently less known to gardeners. It has greatly the appearance of an aphis, and is found dispersed over the under surface of the leaves whilst young, and is always immersed in a globule of honey ; in their more mature state these insects are found congregated round the base of the buds, particularly those which are calculated

1840. AUGUST.

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