"During several years past these pernicious vermin have infested the rose-bushes in the vicinity of Boston, and have proved so injurious to them as to have excited the attention of the Massachusetts Horticultural Society, by whom a premium of S100, for the most successful mode of destroying these insects, was offered, in the summer of 1S40. About ten years ago I observed them in gardens at Cambridge, and then made myself acquainted with their transformations. At that time they had not reached Milton, my former place of residence, and have appeared in that place only within two or three years. They now seem to be gradually extending in all directions, and an effectual method for preserving our roses from their attacks has become very desirable to all persons who set any value on this beautiful ornament of our gardens and shrubberies. Showering or syringing the bushes with a liquor, made by mixing with water the juice expressed from tobacco by tobacconists, has been recommended; but some caution is necessary in making this mixture of a proper strength, for, if too strong, it is injurious to the plants; and the experiment does not seem, as yet, to have been conducted with sufficient care to insure safety and success. Dusting lime over the plants when wet with dew has been tried, and found of some use; but this and all other remedies will probably yield in efficacy to Mr. Haggerston's mixture of whale-oil soap and water, in the proportion of two pounds of the soap to fifteen gallons of water. Particular directions, drawn up by Mr. Haggerston himself, for the preparation and use of this simple and cheap application, may be found in the 'Boston Courier,' for the 25th of June, 1841, and also in most of our agricultural and horticultural journals of the same time. The utility of this mixture has already been repeatedly mentioned in this treatise, and it may be applied in other cases with advantage. Mr. Haggerston finds that it effectually destroys many kinds of insects; and he particularly mentions plant-lice of various kinds, red spiders, canker-worms, and a little jumping insect, which has lately been found quite as hurtful to rose-bushes as the slugs or young of the Saw-fly. The little insect, alluded to, has been mistaken for a species of Thrips, or vine-fretter; it is, however, a leaf-hopper, or species of Tettigonia, much smaller than the leaf-hopper of the grape-vine (Tettigonia vitis), described in a former part of this essay, and, like the leaf-hopper of the bean, entirely of a pale-green color."
"To M. P. Wilder, Esq., President of the Massachusetts Horticultural Society :
"Sir, - Having discovered a cheap and effectual mode of destroying the Rose Slug, I wish to become a competitor for the premium offered by the Massachusetts Horticultural Society. After very many satisfactory experiments with the following substance, I am convinced it will destroy the above insect, in either of the states in which it appears on the plant, as the fly, when it is laying its eggs, or as the slug, when it is committing its depredations on the foliage.
"Whale Oil Soap, dissolved at the rate of two pounds to fifteen gallons of water. I have used it stronger, without injury to the plants, but find the above mixture effectual in the destruction of the insect. As find, from experiments, there is a difference in the strength of the soap, it will be better for persons using it, to try it diluted as above, and if it does not kill the insect, add a little more soap, with caution. In corresponding with Messrs. Downer, Austin & Co., on the difference in its appearance, they say : ' Whale Oil Soap varies much in its relative strength, the article not being made as soap, but being formed in our process of bleaching oil. When it is of very sharp taste, and dark appearance, the alkali predominates; and when light-colored and flat taste, the grease predominates.' The former I have generally used, but have tried the light-colored, and find it equally effectual, but requiring a little more soap, - say two pounds to thirteen .gallons of water.
"Mode of Preparation. - Take whatever quantity of soap you wish to prepare, and dissolve it in boiling water, about one quart to a pound; in this way strain it through a fine wire or hair sieve, which takes out the dirt, and prevents its stopping the valves of the engine, or the nose of the syringe; then add cold water, to make it the proper strength; apply it to the rose-bush with a hand-engine or syringe, with as much force as practicable, and be sure that every part of the leaves is well saturated with the liquid. What falls to the ground, in application, will do good in destroying the worms and enriching the soil, and, from its trifling cost, it can be used with profusion. A hogshead of 136 gallons costs forty-five cents, - not quite four mills per gallon. Early in the morning, or in the evening, is the proper time to apply it to the plants.
"As there are many other troublesome and destructive insects the above preparation will destroy, as effectually as the Rose Slug, it may be of benefit to the community to know the different kinds upon which I have tried it with success.
"The Thrips, often called the Vine-Fretter, - a small, light-colored or spotted fly, quick in motion, which, in some places, are making the rose-bush nearly as bad in appearance as the effects of the Slug. Aphis, or Plant Louse, under the name of Green or Brown Fly; an insect not quick in motion, very abundant on, and destructive to, the young shoots of the Rose, the Peach Tree, and many other plants. The Black Fly, a very troublesome and destructive insect, that infests the young shoots of the Cherry and the Snowball Tree. I have never known any positive cure for the effects of this insect, until this time. Two varieties of insects that are destructive to, and very much disfigure, Evergreens, the Balsam or Balm of Gilead Fir in particular, one an Aphis, the other very much like the Rose Slug. The Acarus, or Red Spider, that well-known pest to gardeners.