ROSA. 



254 



ROSE ACACIA. 



hot-bed, or put into a hothouse the 

 1st of October; those put into the 

 hothouse in November will flower in 

 January and February; and so on, 

 always calculating that the plants will 

 flower about two months after they 

 are placed in the hothouse or frame 

 During the forcing they should be 

 supplied abundantly with water of the 

 same temperature as the house in 

 which they are kept ; and the heat 

 they are kept in should never be less 

 than 60° at night: The China Rose 

 may be made to flower all the winter 

 by keeping it in a greenhouse at 50°, 

 and having pinched off all its flower- 

 buds in summer and autumn. 



The insects that attack Rose-trees 

 are very numerous. Perhaps the most 

 troublesome are the Aphides (see 

 Aphis) which cover the tender shoots 

 in summer and autumn. The cater- 

 pillars of several small moths are also 

 very destructive to Rose-trees. One 

 of these, which is called a leaf-miner, 

 lives within the leaf, where it feeds 

 upon the pulpy matter, leaving traces 

 of its course by a number of pale yel- 

 low zig-zag lines, which are occasioned 

 by the skin of the leaf withering when 

 deprived of the pulpy matter which 

 supported it. The perfect insect is 

 called the red-headed moth (Microse- 

 tia ruficapitella) ; and it is so small, 

 that even with its wings expanded it 

 does not measure more than a quar- 

 ter of an inch. Another very destruc- 

 tive insect is the maggot or grub of 

 one of the saw-flies. The perfect 

 insect, which is a beautiful creature, 

 with transparent wings, lays its eggs 

 in the flower-bud ; and in this the 

 grub is hatched, eating its way out 

 and destroying the petals that it 

 passes through. Other insects are a 

 kind of leaf-rollers, not exactly like 

 those that infest the oak, but a spe- 

 cies of the genus Lyda (belonging: to 

 the Tenthredmidce), which construct 

 a portable case in which they enfold 



themselves, of pieces of leaves, which 

 they cut out and fasten together in a 

 spiral direction. Besides, there is the 

 rose-moth, a species of Tortrix, which 

 fastens the bud, bya number of slender 

 threads, to one of the leaves, which it 

 doubles up like the folds of a fan. 



The only sure remedies for all 

 these insects are hand-picking and 

 frequent syringing. Tobacco- water is 

 also used ; and this is made by pour- 

 ing a gallon of boiling water on half 

 a pound of the best shag tobacco, and 

 letting the decoction remain till it is 

 cold. The infected shoots should 

 then be dipped in the tobacco-water, 

 and suffered to remain in it about a 

 minute, and then washed with clean 

 water. If the tobacco-water be suf- 

 fered to dry on the plants, it will 

 blacken the young shoots ; and the 

 l'emedy will thus be worse than the 

 disease. Lime-water is also some- 

 times used, but no more lime should 

 be put into the water than to make it 

 look slightly milky ; and the leaves 

 should be washed after it has been 

 suffered to remain on a short time. 

 Dipping the shoots in clean water, 

 and laying them on in one hand, while 

 a soft brush is gently passed over 

 them with the other, is also found 

 efficacious. 



Roscoea. — Scitaminece. — Hand- 

 some stove-plants, somewhat resem- 

 bling the Indian shot. They should 

 be grown in loam, peat, and sand ; 

 and they are increased by dividing the 

 root. '\ 



Rose. — See Rosa. 



Rose Acacia. — Robinia hispida. 

 — A very handsome shrub with pin- 

 nate leaves, and long drooping ra- 

 cemes of rose-coloured flowers. It 

 will grow in any soil, but it should 

 be placed in a sheltered situation, on 

 account of the brittleness of its 

 branches, and their liability to be 

 broken off by high winds. See Ro- 

 binia. 



