The enemies of the rose are many. They are of two classes; the insect foes, and diseases caused by Fungi. And their prevention and destruction are tasks, as every rose-grower knows only too well, which call for ceaseless vigilance and constant work, more especially in the early months of the season. For if remedies are applied in good time, the pests of both kinds give comparatively little trouble after May and June until the early autumn, when a fresh crop of both appears.

No such powerful weapon has ever before been put in the hand of the rose-grower, as the remarkable handbook on the Enemies of the Rose, published this spring (1908) by the National Rose Society. For here the veriest tyro can recognize the diseases which puzzle him and the insects which drive him to despair in all stages of their mischievous existence, figured in exquisitely drawn and coloured plates; while in the terse and admirable letter-press he is told how to combat their destructive ways. This little book can be obtained by non-members of the Society for 2s. 6d., through any member; and it ought to find a place on the shelf of every rose lover.

Mildew, of all Fungoid diseases, is the worst we have to contend with. Some roses, such as the lovely H. T. Killarney, the Crimson Rambler, the H. P. Margaret Dickson, and others, are specially subject to this pest; and unless measures are taken against it when the very first sign appears, it quickly spreads to other roses. Two seasons ago a plant of Margaret Dickson had it badly in my garden, and infected its neighbour, Frau Karl Druschki, to an alarming extent.

This odious disease, though more or less always present in the garden, appears generally in marked strength twice in the season—first in spring, when the foliage is just fully developed, and secondly after the midsummer shoots are grown.

It must be attacked early before it gets any hold, in fact, before it actually shows, if we have reason to suspect its presence. Flowers of Sulphur is the most usual and effective preventive. It is blown over the plants with bellows made specially for the purpose. Floating like a fine cloud all over the garden it settles on every part of the plant. The early morning before the dew is gone is the time to apply it, as the evaporation of the dew has some subtle effect on the sulphur which greatly increases its efficacy. Rev. F. Page-Roberts strongly recommends Black Sulphur instead of the ordinary yellow, used with one of the "Ideal" Powder Bellows, made by W. Wood & Son, Wood Green.

Another preventive, which is advised in the National Rose Society's handbook as extremely efficacious, is syringing with Potassium Sulphide, Liver of Sulphur—half an ounce to a gallon of water. The handbook advises adding a tablespoonful of liquid glue, or the whites of two eggs to every gallon of water, as this causes the solution to adhere better to the foliage. If thoroughly and carefully applied with a very fine syringe, such as the Abol Syringe, using the bend attached to get at the under-side of the leaves where the fungus first appears, this wash acts rapidly upon the pests.

Mo-Effic, a new preparation, has been highly recommended in the last two years. I have not tested it myself. But Mr. Mawley considers it most successful.

Black Spot is another troublesome pest. It attacks the foliage alone, and not only spoils the appearance of the leaves, but so injures them that they fall off prematurely. The disease can be best checked by spraying with the Liver of Sulphur wash, beginning early in the spring and going on at intervals.

Rose Rust and Rose Leaf Scorch may also be combated with Liver of Sulphur wash.

But in all these three last diseases, it is a matter of the greatest importance to collect the badly diseased leaves on the plant, and especially to pick up every one lying on the ground, and to see that they are burnt at once and not thrown on the rubbish heap, where they will only infect the soil.

Sooty Mould, the unsightly black stuff which often covers the foliage, is a parasitic fungus not upon the leaf itself but upon the "honey dew" deposited by Green Fly. If therefore the honey dew is kept off by destroying the Aphides which secrete it, Sooty Mould will not appear.

Green Fly, or Rose Aphis, is alas! too well known in every garden to need much description. But the reason why it is so difficult sometimes to get rid of this pest is not so commonly known. The Aphides breathe through pores at the sides of their bodies. And in order to kill them, some substance must be used which will close these pores. Therefore syringing with water or any clear liquid is absolutely useless; for if a few Green Fly are knocked off one shoot they will only settle on some other. We often hear people say after a thunderstorm, "This will clean the roses and wash off the Green Fly nicely." Far from it. They only increase the faster; while the caterpillars rejoice, and flaunt themselves openly on every bush. Then in despair some one uses paraffin or some violently caustic wash for spraying the Green Fly, and destroys his roses thereby.

Nature has mercifully provided some enemies to prey on the Green Fly—and these help in some small degree to keep the pest down. The chief of these is the Ladybird, which both in its adult and in its larval state devours them ceaselessly. The pretty green Lace-wing Fly or Aphis Lion is also useful, as its larvÆ are provided with "large sickle-shaped jaws for picking the Green Fly off the plants."

The Hover Fly—which looks like a small, slim two-winged bee or wasp—lays its eggs in the thick of a mass of Green Fly, and its green and grey leech-like maggots feed upon them. And the Ichneumon and Chalcid Flies lay their eggs in the bodies of the Aphides and their maggots feed on them from within.

But all these are of comparatively little help to the unhappy rosarian, who must therefore devise unnatural means to clear his plants.

As far as I know, with the exception of an Aphis brush—a useful invention, but one which needs very gentle handling—there are only two safe remedies for this universal plague. The usual one is a wash of soft-soap and quassia, in these proportions—

Even this wash, excellent as it is, will sometimes fail to get rid of the scourge in a bad year. But I have found "Abol, White's Superior," a never-failing remedy. It is also much easier to use, as one only has to mix it with cold water according to the directions on each can, and it is ready in a minute.

If either of these remedies are used the moment the Green Fly appears, and the dose repeated a couple of days later in order to kill any that may have escaped the first spraying, we have very little more trouble until the second crop of Green Fly appears in September. It is well to syringe the plants thoroughly with pure water a few days after the second dose of either of these washes, as this knocks off the dead Aphides, and leaves the foliage clean and sweet.

Although paraffin in various forms is often recommended, let me urge upon my readers that it is a most dangerous substance to use upon the rose—a naturally delicate plant—as any remedy of a caustic nature is sure to do it far more harm than good.

Tobacco wash is recommended by the Continental rose-growers for Aphis, 1 part of tobacco-juice to 15 parts of water. If a little soft-soap is added it makes a better wash. This is also a good wash for

Cuckoo Spit or Frog-Fly.—This frothy substance if washed off will be found to contain a yellow creature, often closely wedged into the angle of leaf and shoot, or at the base of a flower bud. This is a "nymph" or young Frog-Fly—a most destructive insect—and unless removed it will so quickly suck the sap of the leaf and bud that it dies and falls off.

To get rid of them requires patience. We must either hand-pick the roses—or if we spray with the tobacco wash it is necessary to syringe the plant with plain water first, using some force, to wash off the white froth—and then spray with the tobacco wash to kill the "nymph."

This leads us to the more active and the worst of all the pests we have to fight against.

Four Beetles are among the enemies of the rose. The beautiful green Rose Beetle or Rose Chafer does harm in both stages. As a grub it feeds underground on the roots; and as a beetle eats the foliage and the petals and anthers of the flowers. I find it is particularly fond of the delicate blossoms of the Yellow Persian Briar.

The Cock Chafer also eats the foliage, and its large white grubs devour the roots of the roses to such an extent that they often kill the plant. As the grubs remain for three years in the ground the damage they can do is incalculable; and they attack other plants besides roses. Among the roots of a herbaceous SpirÆa I lifted this last winter, I caught forty of these grubs, and found they had so honey-combed the roots that the plant had to be burnt.

The Summer Chafer and Garden Chafer also attack roses.

Where these four chafers are prevalent there is no cure but hand-picking. The beetles must be collected off the bushes; and the grubs carefully picked out of the roots, if we have reason to think they are present from the rose appearing unhealthy. Or they may be tempted out of the soil by placing grass turves upside down close to the plants, when they can be picked out and killed with a little boiling water.

The Rose Leaf-cutting Bee spoils the foliage by cutting semi-circular pieces out of the leaves to line its nest. A few years ago I found that a fine young plant of Tea Rambler was so relished by this bee that hardly a leaf was left intact. There is no cure but to watch the bee going into her nest and there to destroy it after dusk.

Of all pests that the rose-grower has to fight against

These loathsome pests are the larvÆ of certain flies and many kinds of moths.

Sawflies, the little black and shiny flies which infest the roses in May and June, are a terrible pest, as the eggs they lay on the leaves turn quickly into small, green larvÆ. There are several kinds of sawflies, and their destructive methods vary. The Leaf-rolling Sawfly, whose larvÆ roll the rose-leaves like paper spills, has become a serious pest among garden roses of late years, and if these rolls are carefully unfolded the little green maggot will be found in one of them. It must be caught with care, as it is very lively, and if allowed to fall to the ground will remain there, and produce a fresh brood in the next year.

The Rose Slugworm is much more common, and most destructive, eating the upper surface of the leaves and leaving the lower to shrivel up. It has two broods in the year.

The Rose Emphytus is another of the sawflies, and one of the worst. Its larva eats the whole leaf away, beginning at the mid rib, and also works its way into a cell in the branches till the next spring, thus killing the tender growths above. This is the green caterpillar which we find coiled up on the under-side of the rose-leaves, or in early morning and late evening curled round the base of a rose-bud, working its way through the calyx into the heart of the flower. It is far easier to catch, as it is somewhat sluggish in movement, clean and hard in substance—and therefore less disgusting to touch than others that squash in one's fingers. The best remedies for these pests are: first, prevention, by spraying with hellebore wash, which I have found most useful. Second, by careful hand-picking when the larvÆ appear. And third, by removing the surface soil in which the cocoons are buried, and all dead wood, during the winter.

Hellebore wash is made in the following proportion—

Mix the hellebore and flour with a little water till dissolved; then stir into the rest of the water and apply with a fine Abol Syringe.

Caterpillars of many moths are among the most deadly foes of the rose. Some eat the foliage—such as the Buff Tip and Vapourer Moths; others tunnel into the leaves. But the worst of all are the Tortrix Moths or Rose Maggots, whose repulsive grubs eat the unopened blossoms and spin the delicate young leaves together, destroying the whole top of the new shoots. There are many varieties of Tortrix, which are all quite small moths, and their caterpillars or "Maggots" are the most unpleasant and destructive of all we have to deal with. The worst of all are the Red and the Brown Rose Maggots. These creatures are dirty red or brown, with black heads; they are soft, and grow very fat, and when full grown are half an inch long. They spin the leaves together at the top of the tender young flowering shoots, often bending the top down; and not only eat the leaves in the midst of this filthy fortress, but eat their way into the buds and destroy them.

Other Tortrix Moths have green and yellow-green maggots. The worst is the Green Rose Maggot—bluish-green with a black head. It also spins the leaves together, and grows nearly as large as the brown. It is extremely active, and very soft and slimy.

These all turn to pupÆ among the leaves instead of in the soil; and any left in the foliage must be picked out and burnt. If we wait until the shoots and buds are eaten and the foliage spoilt—nay, till often the whole of our early flowers are ruined—the only remedy is to pinch the leaves which conceal the maggot, if we have courage to do so, or to hand-pick every one we see. But happily a way exists of preventing these loathsome pests from destroying our roses. And this is to spray the plants from the middle of April to early in May with arsenate of lead.[9] This should be done twice, and will prevent many other caterpillars from feeding on the foliage.

The Vapourer Moth, the little golden brown moth with a tiny white crescent on each wing, is unfortunately common everywhere, in town as well as country; and its caterpillars are as destructive as they are beautiful. These caterpillars are found in great masses upon the hawthorn and fruit trees, and attack the rose as well. They are handsome, hairy creatures, spotted thickly with bright pink-red tubercles, with four erect tufts of yellow hairs on the back, and five longer tufts of darker hairs, two pointing forwards, one backwards over the tail, and two at the sides.

If there are too many to be hand-picked the bushes must be sprayed with arsenate of lead.

The Buff Tip Moth does most harm in the autumn, when its caterpillars, yellow and green, with longitudinal black lines divided by yellow bands, appear in colonies, feeding upon the surface of the leaves. They should be picked off at once, before they grow large, as they reach a length of two inches when full grown, and disperse, feeding singly. If very plentiful, spraying with arsenate of lead will destroy them.

The Winter Moth, which is such a serious pest among fruit trees, also attacks roses. The caterpillar is hatched very early, in the end of March and beginning of April. It is a "Looper," greyish at first and turning green later, and nearly an inch long when full grown.

The grease bands we use on fruit trees to catch the wingless female as she creeps up in the autumn to lay her eggs on the bark, would be difficult to use for rose-bushes. The only plan therefore is to spray very early in the season with arsenate of lead wash.[10]

Another "Looper" found early on the roses is that of the Mottled Umber Moth. It is brown with yellowish sides, looks almost like a twig, and is over an inch long. It must be hand-picked.

The Dagger Moth's caterpillar—a long, grey-black creature with a yellow line along the back, a large black hump on the shoulder and a small one at the tail, is most destructive when it appears in late summer and early autumn. It is generally found singly; but one specimen will strip a whole shoot of leaves, leaving only the mid rib. Hand-picking is the only remedy.

These are the chief of the pests which we have to fight against. And if we desire to keep our roses in health and beauty we must remember that prevention is better than cure, and begin our treatment in good time, before the many enemies of the rose get too firm a hold.

REMEDIES FOR ROSE PESTS

For Aphis or Green Fly.

Dissolve the soap in boiling (soft) water. Boil the chips or simmer for twelve hours, adding water from time to time to cover them. Strain off the liquid, mix it with the dissolved soap, stirring them together thoroughly, then add the water.

Mix the flour and hellebore powder with a little water. Then add the rest of the water. It must be kept stirred, and used with a fine spray. Hellebore is poison.

This is a poisonous wash, but the only one that can be used without hurting the roses. It is made with the paste known as Swift's Arsenate Paste, mixed with water.

Liver of Sulphur Wash for Mildew and other fungi, and for Red Spider.

Powdered hellebore may be dusted over the bushes for Sawflies, but the hellebore wash is best.

All these washes can be used with the Abol Syringe. And in large gardens Vermorel's Knapsack Sprayer is almost indispensable, as it does equally well for roses and fruit trees.