The insect enemies of the cauliflower are the same as those which attack the cabbage and other related plants. The four here mentioned require to be specially guarded against. In preparing these notes I am indebted to Mr. L. O. Howard, of the Department of Agriculture, at Washington, for essential aid.

Flea Beetle (Phyllotrea striolata, Fabr).—This insect, also known as the "ground flea" or "Jack," seldom attacks the plants except while growing in the open ground, and is most troublesome in warm, sheltered situations. A safe preventive, therefore, is to grow the plants in beds or frames elevated about three feet from the ground. The objection to this method, aside from the extra labor involved, is the necessity of almost daily attention to see that the soil does not dry out. A supply of water must be conveniently at hand if this method is used, and it is desirable also, to prevent the beds drying out too quickly, to have the earth at least eight inches deep. In hot-beds this insect is seldom troublesome, being probably repelled by the fumes from the manure used. When the seed is sown in the open ground, as practised by many large growers, an extra quantity should be used to ensure against almost certain loss of some of the plants by the flea beetle. The soil should be rich and fine, so that the plants will pass the critical stage as quickly as possible. Sowing radish seeds with the cauliflower is practised by some, as this seed costs but little, and the radishes, coming up first, are attacked by the fleas, which, to some extent, saves the cauliflowers. When the fleas appear, almost any kind of dust will keep them in check somewhat. Lime and ashes are used, but plaster, which adheres to the leaves better, seems equally good. I have had good success with rancid fish oil, mixed as thoroughly as possible with water and sprayed upon the plants. An emulsion made of the oil, in the same manner as hereafter described for kerosene, would enable it to be used to better advantage. A decoction of tobacco, or fine tobacco dust, are standard remedies for this insect.

Cut Worms.—Cauliflower plants being fully twice as valuable as cabbage plants, and it being of more importance to have them started at the proper time, it is necessary to give greater care to protect them from cut worms. Absolutely clean land contains no cut worms, but such land is seldom used on which to plant cauliflower. Sod land, which is generally used, is nearly always full of cut worms. A multitude of remedies have been proposed for this pest, but few of them are of much value. The worms are most abundant and destructive in the latitude of New York during the month of May. Fortunately, cauliflowers are usually set out either earlier than this, for the early crop, so that they become well established and out of reach before their depredations seriously begin, or else, for the late crop, they are set toward the last of June, after the worms have begun to pupate, and are no longer troublesome. Until recently, digging and killing the worms by hand seemed to be almost the only practical remedy. Of late years, trapping the worms under bunches of grass or cabbage leaves, scattered over the ground preparatory to setting the plants, has been successfully resorted to. An improvement upon this method, recommended by the Entomologist of the United States Department of Agriculture, is now in use, and gives excellent satisfaction. It consists in poisoning with Paris green the leaves used to trap the worms, so that there is no need to collect and kill the worms by hand. A good way to do this is to spray with Paris green, in the usual way, a patch of young clover, then cut it and scatter it in small bunches over the cauliflower field a day or two before setting the plants. For the protection of a few plants in the garden, an effectual preventive against cut worms is to surround the stem with a cylinder of paper or tin. This need not touch the plant. One should expect to lose some plants, however, by cut worms, and be prepared with good plants to fill the vacancies.

Cabbage Maggot (Anthomya brassicÆ, BouchÉ)—Dr. J. A. Lintner, State Entomologist of New York, says of this insect: "This is probably the most injurious species of the AnthomyiidÆ, as its distribution is very extensive, both in Europe and America, and it has shown at times such capacity for multiplication as to cause the entire destruction of cabbage crops. It commences its attack upon the young plants while yet in the seed-bed and continues to infest them, in several successive broods, until they are taken up in the autumn. The larvÆ operate by consuming the rootlets of young plants, and by excoriating the surface and eating into the rind of older ones, or even penetrating into the interior of the root. When they abound to the extent of seriously burrowing the stalk the decay of the root frequently follows in wet seasons, and entire fields are thus destroyed."

The same insect attacks the turnip, cauliflower, and probably other plants. A closely related species is very injurious to the radish. The presence of the insect most frequently becomes manifest upon the cauliflower about two weeks after the plants are set out, and is recognized by the plants ceasing to grow, and wilting or assuming a bluish appearance. Such plants should be at once removed, together with the earth immediately surrounding the root, and fresh plants which have been held in reserve set in their places. The only satisfactory remedies are preventive ones. The seed-bed should be composed of soil taken from the woods, or at least from some place where no cabbages or similar plants have been grown. But the most important precaution is to avoid growing the crop year after year upon the same ground, especially after the insect has made its appearance.

The following remedy, given by Francis Brill, in his pamphlet on "Cauliflowers," is worthy of careful trial. Mr. Brill says: "The ravages of the root maggot have made the growing of early cauliflower, and even early cabbages in many sections, almost an impossibility, but there is a remedy, when the maggot has attacked the roots of the plants, which may be known by a tendency of the leaves to wilt and droop in the heat of the day, very much the same as when affected by club root. Dissolve Muriate of Potash (analyzing 45 per cent. actual potash) in water in the proportion of one tablespoonful to the gallon; or double the quantity of Kainit or common potash salts (13 per cent. actual potash). Apply this directly to the roots, about one gill to each plant, whether seemingly affected or not, for the maggot will have done much harm before the plant will show it, repeating the application as occasion may seem to require. In sections where these maggots have been prevalent it will be well to make a solution of half the above strength, and when the plants are nicely started apply in the same manner as a preventive. Care and judgment must be used not to overdo the matter, thereby killing the plants as well as the maggots. Experiment a little at first."

H. A. March, of Washington, says: "The best thing that I have found for the maggot is a poor grade of sulphur, sulphur before being purified, that smells very strong. Sprinkled over the plants it seems to drive the fly away."

Cabbage Worm (Pieris rapÆ, Koch).—The imported cabbage worm, now known all over the country, is the most troublesome enemy which attacks either the cabbage or cauliflower, and the most difficult one with which to deal. It seldom wholly destroys the crop, and is generally a little less destructive after a few years than it is at first, being kept in check by its natural enemies. It never disappears, however, and its numbers cannot be materially diminished for any length of time by artificial means. Among the partial remedies in use are the following:1. Catch the butterflies with a net when they first appear in spring, before they have laid their eggs. This may keep the insect in check for a year or two when it first makes its appearance, as the butterflies are comparatively slow fliers, and may be caught without much difficulty by a spry boy, especially in the morning when the air is damp.

2. Early in the season keep the young plants excluded from the butterflies, and the whole place free from everything else of the cabbage tribe, except one or more patches of rutabagas or rape, on which the butterflies will lay their eggs. This piece is to be then plowed under.

3. Hand pick the worms from the plants after they are set out, for the first one or two hoeings, or until the worms become very numerous.

4. Spray with kerosene emulsion, made by using two gallons of kerosene, one-half pound of common or whale oil soap, and one gallon of water. Dissolve the soap in the water, and add it, boiling hot, to the kerosene; then churn, while at least warm, for five or ten minutes, by means of a force pump and spraying nozzle, until the mixture loses its oiliness and becomes like butter. When used, dilute one part of the emulsion with about fifteen of water, and spray it upon the plants by means of a force pump and spraying nozzle. This emulsion is also excellent for the cabbage louse and many other insects. In the report of the United States Department of Agriculture for 1883 may be found a description and figure of a suitable spraying apparatus.

5. Pyrethrum, one ounce to four gallons of water; or, better still, mixed one part with about twenty parts of flour and applied while the dew is on, is an effectual remedy.

6. Hot water, at 130° Fah., will kill the cabbage worms and not injure the leaves. Boiling water, placed in sprinkling cans and taken directly to the field, will be about the right temperature by the time it can be applied. Experiments with a few plants may be needed to enable one to get just the right temperature to kill the worms and not injure the plants.

7. Take half a pound of London purple to thirty pounds of finely pulverized dust of any kind, the finer and drier the better; mix thoroughly, passing all through a meal sieve. Dash a small pinch into the heart of the plant, so that it will settle as dust on all the leaves. Repeat after every rain. Half a pound will serve for one application over forty acres. Store any that remains in a very dry place until again wanted.

8. Professor Gillette, of Colorado, finds the best remedy to be Paris green, thoroughly mixed, one ounce with six pounds of flour, and dusted lightly over the plants while the dew is on.

FUNGUS DISEASES.

There are several parasitic fungi which are more or less destructive to the cauliflower at different stages of its growth. The principal diseases of the cauliflower due to fungi are the following:

Stem Rot.—This is an old disease, which attacks the cauliflower, cabbage and other vegetables in wet seasons. It has received various other names, such as "consumption," "humid gangrene," etc. Professor Comes,[B] who has studied this disease in Italy, believes it to be the same as the "humid gangrene" which occurs in Germany, and which is there attributed to the parasitic attack of the fungus known as Pleospora Napi. He finds this and other fungi present, but does not himself consider them the direct cause of the disease, which he attributes solely to the abundance of manure and moisture in the soil, and an excess of water in the plant, at a time when it is subject to sudden changes of temperature. Beyond a doubt, however, the real cause of the disease is the presence of one or more fungi, whose development is favored by the damp weather. The subject requires further study.

In this country this disease has been reported from Michigan, New York, Maryland and Florida. On Long Island, in 1889,[C] the cauliflower crop was almost entirely destroyed by this disease, which was attributed to the heavy rains at the time the plants were heading. Some fields were a total loss, and from the best fields many of the heads spoiled before they reached the market.

No satisfactory remedy is known for the disease. The avoidance of damp soils and locations would be of some benefit, but is hardly practicable with the cauliflower. Wide planting is practiced on Long Island in order to diminish the tendency to the disease. It undoubtedly has this effect to some extent, by permitting a more free circulation of the air, thus drying up the moisture on the plants and thereby lessening the opportunity for the germination of the spores. The increased distance may also diminish the chance of the spread of the spores from plant to plant. When this disease appears upon the early crop in hot-beds or cold frames it may be kept somewhat in check by giving as much air as possible, and taking care not to apply water to the leaves.

Damping Off.—This is usually due to a species of Pythium (a fungus closely related to that which causes the potato rot), which attacks the young plants soon after they germinate. The remedy is, to give the plants plenty of air until their stems become strong enough to resist its attacks. An additional precaution sometimes employed is to grow the plants in pans or small boxes and water them only by setting these in a tank of water of nearly the same depth, allowing the water to soak into the soil, but not touch the plants. The disease is seldom troublesome on plants grown thinly in the open air. If it makes its appearance, water thoroughly, but not too often, and sprinkle dry sand over the seed-bed among the plants.[D]

Black Leg or Mildew.—This is a disease which attacks the stems of young plants which are being wintered over. It is undoubtedly due to one or more species of parasitic fungi, but I do not find that the subject has been studied. Doubtless the rupture of the bark by alternate freezing and thawing gives the fungi an opportunity to attack the plant. The disease is prevented and kept in check by keeping the seed-bed dry. An occasional dressing of sand, lime, wood-ashes or rubbish of any kind, is useful.

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