can fly, from orchard to orchard. The remedy is very simple; the black wart can be cut out with a sharp knife even when of the size of a pea, and the sooner it is done the better for the tree.

The Lombardy poplar and the locust tree have suffered by the ravages of this insect; if the former were worth our care, it could be easily made to flourish again. As the locust is both ornamental and useful, a very little attention, until the tree is five or six years old, will keep off the insects. In this tree, as well as the Lombardy poplar, the excrescence formed by the insect is not black, as on the plum and cherry tree, but of the natural colour of the bark. But let the insect be what it may, or the mode of depositing the eggs ever so peculiar, we still perceive that no instantaneous blight is the consequence of it.

Having mentioned the Lombardy poplar, we shall observe, that, in common with other naturalists, we accounted for the decay of those trees on the supposition that as the twig, or slip, is part of the parent tree, it must partake of its nature, and be subject to the same laws of vitality. But we have changed our opinion on this subject; and having already detailed them at large in a late article on vegetable physiology,' we shall only observe that the ragged and forlorn appearance of the poplar is entirely caused by the insects that puncture the bark near the articulations. We have seen large trees decay gradually from this cause, but still there was no shrivelling or blackening of bark, or leaves; the latter remaining firm and green to the last.

It is to render an introduction to the horticultural art easy and pleasant, that we take the business of advice out of the hands of regular teachers; but we wish our friends the nurserymen to understand that we do not imagine them to stand in need of any advice we can offer. If we can instruct others, the nurserymen will find great advantage in it, as an ignorant purchaser is of serious injury to them.

It is not the fault of the nurseryman, altogether, that our orchards present such a piteous spectacle as they often do, after years of labour and reasonable expectation. The fault is as much owing to the ignorance and unskilfulness of the purchasers themselves-the want of horticultural knowledge being very apparent. We shall, therefore, throw out a few hints for the guidance of those who have not had a regular training.

Let them understand, therefore, that while trees are young, the ground can be cultivated between them with light crops, such as buckwheat, melons, or potatoes; that is, provided these crops have been well manured. But after the trees begin to bear, a crop of vegetables, or grain, should never be taken from the soil, unless full half of their value has been expended in manuring

1 See American Quarterly Review, March, 1837.

them. As to the mode of distributing manures in an orchard, either for the trees alone, or for a crop between them, long experience has taught us that, under every circumstance, the broadcast method is the best. This mode is far more beneficial to trees than when certain portions are applied to the area of each tree. Buckwheat, sowed twice during the summer, and ploughed in lightly, is a cheap and excellent manure; the advantage of ploughing in such crops as buckwheat and weeds we shall proceed to state.

No crop should be allowed to arrive at maturity, that is, to form seed, after the trees are six or seven years old, unless they are full fifty feet apart; nor yet should the ground remain uncovered, and exposed to the scorching rays of the sun. This practice would be more injurious to the trees than the exhaustion from a seed crop; but before we go into further particulars, let us take a view of vegetable life.

For what purposes do trees grow, and why does fruit ripen and fall to the ground? The answer is ready for the embel lishment of nature, and for the gratification of man. It is not our intention to touch on the delicate subject of sensation-a feeling which many philosophers imagine a plant to possess, and which certainly implies a capacity to suffer either pain or pleasure-nor shall we descant on the beauty of vegetation, independently of its use to man. We shall advert solely to the course that nature takes in these operations--a course which the dullest observer cannot fail to understand.

But whichever way we proceed in the investigation, whether we view a plant as ornamenting the earth--as it relates to the individual enjoyment of the plant itself, or as it regards the gratification of man--we shall perceive that it is effected by one very simple and beautiful contrivance, a contrivance that is to perpetuate vegetable life as long as the earth exists--this is the production of seed! This seems to be the whole effort of the plant, and to bringing the sced to maturity every thing is made subservient.

It cannot be solely for the gratification of man's appetite that the fruit or seed of plants is formed and protected with so much skill and care, else the gigantic plane tree, and the lofty pines, would have the fleshy covering of their seeds of so palatable a nature as that man would appropriate them to himself. There are certain bounds which the Creator has set to our enquiries, else we should not remain ignorant of the cause which renders fruits so different in their nature and quality when growing in the same field, and nourished by the same food; or why the same fruits are refreshing and nutritive in one latitude, and unwholesome and unpalatable in another. The pulp, or fruit, as it is called, and which man considers as formed for his own VOL. XXI.-NO. 42.

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exclusive use, is nothing more than a covering which is to nourish and protect the seed until it arrives at maturity. That the pulpy rind is palatable, is owing to the wisdom of the Creator, who, foreseeing that man would do nothing unless he sees some immediate benefit to himself, rendered the rind of the seed, or fruit as we call it, an object of desire. Thus it is, indirectly, that the necessity of preserving the seed is implanted in our bosoms.

There are many trees that have their seeds likewise protected by a rind, which our sagacity detects as injurious and our taste as unpalatable; yet useful and necessary as the wood of these trees is to the arts, they would soon perish if nature had not endowed them with a capacity to assist themselves. The rind or seed of forest trees, for instance, is of no use as food to man, but owing to their minuteness and levity they are blown to a distance by the wind, and fall on some spot where there is room for them to take root and expand to the size of the parent tree. But with the trees that bear fruit the case is different. Pear, plum, apple, peach, and quince trees are of small size compared to those of the forest; the branches, therefore, cannot throw their fruit to a distance, for this fruit is large, heavy, and very juicy. It would, when the seed is ripe, fall to the ground immediately under the tree, where, if it germinated at all, it would be at the expense of the parent tree. But as it is an object of intense desire to man, he gathers it carefully, and after devouring the rind he plants the seed at judicious intervals.

It seems therefore to be the peculiar object and care of nature to throw every facility in the way of maturing the seeds of all plants, from the chickweed to the oak. The same

process is observed, the same effort is made, in bringing the seeds of useless and noxious weeds to maturity as in those of the largest tree in the field. For this purpose nature takes advantage of all the changes that decayed vegetation undergoes. As in the beautiful language of Scripture, a sparrow does not fall to the ground unobserved, so a poor weed is not trodden under foot without the knowledge of a kind Providence, who immediately converts it to some use. All the decayed matter— all the manures which are placed in a field for the sustenance of a crop-are converted into food. It is the business of the plant, therefore, to imbibe as much of this as will serve for the maturity of the seeds. The greatest exhaustion of soil takes place during the period of the ripening of the seeds; until that time arrives, what are called the nutritive particles of manures are not carried up in such abundance.

A thick, full crop of oats-one of the most exhausting of grains will appropriate all the nourishment which a well

manured field affords. It will therefore be at once understood why trees perish or are stunted, when planted in grain fields or among biennial grasses. The sap vessels of grain and other annual and biennial plants are more ductile-are more greedy of nourishment than those of the hardy, woody fibre, such as trees and shrubs. The gases which propel all the nutritive. fluids, find a readier admittance in the spongelets of succulent, rapidly growing plants, than in those of trees and shrubs. Of course, as the universal law respecting gases obliges them to rise upwards and get into space as quickly as possible, they naturally rush to the easiest point of access. It is much easier for gases to elevate themselves by following the course of the sap vessels of a plant than to rise immediately from the soil, because they are charged with certain elementary particles, the greater part of which is abstracted by the plants, thus leaving the gases at greater liberty to ascend into space.

In this view of the case all light crops should be considered as manure; and therefore must be ploughed under before the gases extricate the best of the nutritive particles from the rich soil to bring these crops to seed. We observed that the most valuable portions of it are absorbed by the spongelets which the seed is maturing. If no weeds or other light crops were allowed to abstract this aliment, the gases would find the spongelets or the roots of trees the next best point of entrance for the purpose of elevating themselves. It is in this way, therefore, that trees are benefited by the absence of other vegetation near to them.

Turning down the soil, with the plough or spade, confines the alimentary particles to a stratum whence they can be available to the spongelets of the roots of trees. Even should there be no light succulent crops of grass or weeds, the mere turning down the upper surface of the soil would be beneficial to trees in another sense. Gases can deposit the particles with which they are charged with greater ease when they are allowed to move in a fluid medium. The soil, being moved, has its upper dry surface turned down, and the moist earth then becomes the surface, and it is from this damp medium the gases have an easy transit. We have elsewhere entered more minutely into the subject of gaseous action, and shall say no more at present than that gases always effect their object through a fluid medium; and when deprived of this they move at random.

We hope that we have sufficiently explained why trees should be allowed to absorb all the nutritious particles of manures, and why no other crops should be allowed to produce seed near them. In the article on Vegetable Physiology we have gone more at length into the rationale of the principle, and to that we refer those who have a curiosity on this interesting subject.

Our present purpose is confined to the mere practical details of horticulture, yet we thought the few digressions made in theoretical explanations would materially assist the cultivator in his views,

We here enter our protest against tall trees, whether of the fruit or ornamental kind. It is the practice to trim trees up very high. This was done by the nurserymen to facilitate the packing of them in bundles for exportation, and ignorant persons required that they should be so trimmed that the plough might go closely to the tree. Nature works for us more judiciously than we do ourselves; she points out the true mode and the exact time when an operation of this kind should be performed. A tall tree with a slender body is blown about severely by our high winds and equinoctial gales. This violent motion ruptures the spiral and other delicate vessels, and thus renders them unfit to elaborate the sap and other secretory matter. The body bent and twisted in every direction, is unable to support the weight of the branches, and of course the tree presents a crooked and unsightly appearance.

A tree that is allowed to grow low will bear the vicissitudes of weather much better than if trimmed up; the body grows stout and the limbs spread finely, making an ample shade to protect the roots from the sun and heavy rains; a beautiful provision of nature! In process of time, as every one has observed, the under or first branches of a well-shaped tree become crooked and get out of the centre of gravity, giving way to other branches that grow above them, just like the process of teething in children. By cutting off these crooked, under limbs, which all disappear piece by piece in the course of time, we give more height to the tree at the precise time when it is proper to do it. When these first branches, like children's first teeth, are gone, the next set come out boldly, and maintain their proper horizontal position during life. Mr. Mark Harden has an excellent paper on this subject in one of the early numbers of the American Farmer.

As it respects grafting, the greatest choice exists with respect to the buds. All nurserymen know-at least they ought to know that if a tree is grafted from a scion cut from a horizontal limb, it will bear fruit much sooner than if the scion were cut from an upright limb. Those slender water sprouts— which from their length and smoothness are so seducing to a scion cutter, and from which he can cut three or four graftsare utterly unfit for the purpose. A tree grafted with one of these scions takes a longer time before it bears fruit; pear trees throw up a great abundance of these water sprouts from the central limbs, and if young trees are grafted from them, they are very tardy in bearing. These water sprouts, or vertical