Part 62

PLUMS AND THEIR ENEMIES.

Multitudes of men have had plum-trees, and every year, for ten years, have seen the fruit promise fair at first and then prematurely drop, without knowing the reason. Even well-informed men have said to us that it arose from some defect in the tree, from too much gum, from a worm at the root, etc.

The plum-tree is very hardy; is less subject to disease than most fruit-trees; its fruit is highly prized; and the varieties of it are numerous and many of them delicious. By a proper selection of trees a succession of fruit may be had from July to November. The trees are usually sure and enormous bearers, every year. With so many good qualities the cultivation of the plum is well-nigh prohibited, as a garden or orchard fruit, by the valor of one little bug!

The Curculio (a very hardy fellow, with a constitution yet unimpaired by such a name as Rhynchœnus Nenuphar!) is a small beetle, about a quarter of an inch long, which attacks the plums almost as soon as the fruit has set. They seek this, and almost all smooth-skinned fruits, as a place of deposit for their eggs. Many of the facts which we shall narrate, were mentioned to us by Mr. Payne of Madison, who has closely and curiously observed this depredator.

An incision is first made, of semicircular form, by a little rostra or lancet which he carries in his head for this very purpose. After the opening is made, the curculio deposits an egg therein; then changing positions again, it carefully, with its fore legs, secures the egg in its nidus, and pats the skin under the edge of which its treasure is hidden, with repeated and careful efforts of its feet. Where fruit abounds it deposits, usually, but one to a plum. But we have had trees, just beginning to bear, whose few plums were scarified all over.

The egg hatches to a worm, and this feeds on the plum, causing it prematurely to fall; the insect issuing from it, enters the ground, to undergo its transformations, and soon to reappear, a beetle, ready for fresh mischief-making propagation.

The climate of the West is entirely glorious for all manner of insects. They can put the East to shame in the matter of aphides, cockroaches, cutworms, army and wire-worms, curculios, peach-worms, grubs, etc., etc. There are many questions relating to the history of insects, about which eastern writers are in doubt, not at all doubtful with us.

1. Do the larvæ remain in the ground all the residue of the summer, and come forth only in the ensuing spring? In cold latitudes it may be so. Harris says, that they undergo their transformation in twenty days. Downing admits this of a few stragglers. But the main supply of bugs, he thinks, remains all summer and until spring, in the ground. But with us the curculio is not exclusively an early summer insect. It is found, in its appropriate haunts, through the whole warm season. Mr. Payne put plums containing the worms into a glass, and in eleven days obtained full-grown curculios. In cool regions they probably have but an annual generation; but in warm and long summers, in the West, they reproduce often in each season.

2. The mode of ascent has been a matter of doubt. J. J. Thomas, in the Fruit Culturist says: “It has the power of using its wings in flying; but whether it crawls up the tree or ascends by flight, appears not to be certainly ascertained.”

Downing admits that it flies, but says, “How far this insect flies is yet a disputed point, some cultivators affirming that it scarcely goes further than a single tree, and others-believing that it flies over a whole neighborhood.”

Kenrick says: “They crawl up trees,” and he quotes an author as saying: “That of two trees standing so near each other as to touch, the fruit of one has been destroyed and the other has escaped; so little and so reluctantly do these insects incline to use their wings.” Dr. James Tilton says, in the “Domestic Encyclopedia,” that “they appear very reluctant to use their wings, and perhaps never employ them but when necessity compels them to migrate.”

It is true that the curculio, in cold and chilly weather, is disinclined to fly; but give it a right murderously hot day, and “McGregor’s on his native heath again.” Just before a thunder storm, in summer, in a still, sultry, sweltering day, they may be seen flying among the trees as blithely as any house-fly; alighting on your arm, or hand, and springing off again as nimbly as a flea.

All remedies founded on the idea of their crawling preferences will be signal failures. Troughs about trees, bats of wool, bandages of all kinds about the trunk to impede the ascent will be found as useful as would high fences to keep crows from a cornfield, or birds from the garden.

All remedies for this pest succeed to a charm where the curculio does not abound; and almost every one of them fails in places really infested them.

In cities, and in country places which are far removed from all orchards or gardens, the crops may be saved. It is not difficult to defend a tree against all the curculios that are bred upon it. Pavements; hard-rolled gravel; gathering up, daily, the fallen plums and destroying them; the application of salt, and many other remedies may succeed where the curculio from other gardens or orchards cannot easily migrate to supply the trees with a fresh brood. Trees in cities, and in retired places, on this account, often bear plenteously.

But of what use is it to destroy five hundred larvæ, if twice that number of emigrants, from some other quarter, are anxious, the next spring, to squat upon your trees, or to enter them, in land-office style, most nefariously? All remedies founded on the destruction of the larvæ will be totally useless if your trees can be reached from some infected point abroad, as we have found to our sorrow. In our own experience, and in that of other amateur-cultivators of fruit, the pavement, salt, and all have been “love’s labor lost.” But in the experience of others, in climates where the curculio does not abound, or in secluded situations, they have proved effectual.

The remedies to be employed, in ordinary cases, must be such as will constantly molest the insect at his work. Inclosures, in which swine root, and rub against the trees; lanes, where cattle resort, to rub off their hair in spring, to shade themselves in summer—these are the best situations. In yards and gardens plum-trees should be placed upon the most frequented paths; close to the well, by the kitchen door, near the wood-house, so that, as often as possible, they may be jarred in passing and repassing.

Where a few trees stand apart in the garden, it is said that, daily, morning and evening, by spreading a sheet under them, and giving the tree a sudden and violent blow with a mallet, the insects will drop and may then be gathered and destroyed. This should be performed while it is cool, as then, only, the curculio is somewhat torpid. If this course is pursued, a block should be put upon the tree, to receive the stroke, with a bit of carpet or some soft pad to it, that the bark may not be injured. A white sheet should be spread under the tree to catch the falling robber.

A few trees will suffice for a private family, and the fruit must be earned by careful watchfulness. Those who are too indolent, or careless, or indifferent to the luxury to bestow the requisite attention through the months of May and June, may spare themselves the trouble of planting plum-trees. Plum orchards are not to be thought of.

Although the curculio chiefly delights in the plum, it scruples at no fruit. It may be found upon peaches, cherries, nectarines, apricots, gooseberries and currants.

ROOT GRAFTING.

While nothing can be done out of doors in the nursery, the process of root grafting may be carried on, and the stock be ready for setting as soon as the grounds are open in spring.

When this method of grafting is employed with discretion, it greatly aids the nurseryman. It is a resource in case he cannot procure stocks to bud or graft upon; it makes finer and handsomer trees; and it can be carried on at a season of leisure; and the scions, being early in the ground, have a longer season of growth by two months than buds, or ordinary grafts.

Although any healthy root with some fibres will answer to graft upon, yet experienced nurserymen prefer the tap roots of young seedling stocks. Those who have apple and pear stocks which are to be removed, should employ the open weather of winter to raise them. The tap roots may be taken for grafting purposes and the stocks put away in cellars, or buried in the ground.

We do not know that there is any difference in favor of the root of one variety over another; but it will not do to propagate every variety of fruit by this method. Experience has shown that some sorts do better by root grafting than in any other way; but other kinds are very apt to be winter-killed; and some varieties have such a straggling habit of growth, that it would be extremely difficult to train them to a good head; and such sorts, therefore, require to be budded or grafted high up on good stocks.

The roots being washed, are cut into four or five inch pieces; and the scions prepared as for ordinary grafting. Splice, or tongue grafting is the most convenient method. Woollen yarn, cut to ten or twelve inches’ length, is wound around it closely at the point of junction. Let the grafting wax be kept in a melted state, by being put in a pan, over a few coals. Holding the work over the pan, with a spoon pour a portion of the liquid all over the yarn; it hardens immediately, and the whole may be set in rows in a box and covered above the point of union with moist sand, and kept in a cellar till it is time to turn them out in the spring.

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The cherry, plum, pear and apple trees, in a diseased condition, will often throw up numerous and thrifty sprouts that will offer to an inexperienced cultivator inviting temptations to multiply his stock at a rapid rate with little labor. If he be deceived by these appearances, and propagate his valuable kinds upon these diseased growths, his efforts will ultimately result in his disappointment.