Powdered white hellebore, dusted on the foliage, or the solution of whale oil soap mentioned for the Rose Thrip, will keep it in check.
White Grub
An underground enemy that feeds on the roots of rose plants. The withering or sickliness of the plant is sufficient reason to cause a thorough search to be made by lifting it. The grub, which is provided with six legs near the head, and which coils itself into a crescent shape when in repose, is particularly fond of strawberry plants, so it will be well to keep these some distance away from the rose garden.
There is no insecticide that will be effective, because of the underground point of attack. Lifting the plant and removing the grub is the only thing that can be done.
Bark Louse or White Scale
This appears when the rose bush is grown in a damp, shady place. It is snow white and individual scales are about one-tenth of an inch in diameter, irregularly round.
Cut off and burn badly infested shoots. Spray with 1 lb. of soap in 1 gal. of water in early winter and again in early spring. Weaker summer applications may be used also—1 lb. in 4 or 6 gal. once in three weeks throughout the season will reach all the larvæ.
Our Allies
It is well to remember that there are friends of the rose in the lower animal world as well as enemies—the toad, lady-bug, ground-bird and swallow, particularly. The toad is sometimes brought by the English gardeners from a distance to help wage war on the pests; the lady-bug may be passed thankfully by when seen; and it may be well to try attracting the birds to the rose garden by scattering a few crumbs there daily—not too many, but just enough to arouse a real appetite for insect pests.