ROSA 



ROSA 



2983 



3433. A spray of rose hips. 



often remain on the branches all winter. The red stems 

 of most of the species of the Carolina? and Cinnamomeae 

 groups are effective in winter also. The foliage of most 

 of the American species turns purple-orange or yellow 

 in autumn, and so does that of R. rugosa, which is, in 

 regard to the foliage with its dark green leathery and 

 glossy leaves, the handsomest of the hardy roses. 



With few exceptions the roses are of easy cultiva- 

 tion and grow in almost any kind of soil, except in a 

 loose and very sandy one. They are readily trans- 

 planted. The wild roses need little pruning; they should 

 only be thinned out and the weak and old wood be 

 removed: long and vigorous shoots should not be 

 shortened, especially in the climbing varieties, as these 

 shoots are the most floriferous. 



All true species can be propagated by seeds, but as 

 roses are likely to hybridize, only seeds taken from 

 isolated plants ought to be used. The hips should be 

 gathered as soon as ripe, the seeds washed out and sown 

 at once or stratified and sown in spring. They germinate 

 the first year, but if kept in the hips during the winter 

 and allowed to become dry, they usually do not germi- 

 nate until the second year. Mice are very fond of the 

 seeds. Almost all species grow readily from cuttings 

 of nearly ripened wood in summer under glass. Many 

 species, especially the climbing roses, can be propa- 

 gated by hardwood cuttings taken in fall and planted in 

 spring. Layering is less often practised, except with a 

 few species, like R. foetida and R. hemisphaerica, which 

 do not grow readily from cuttings. Some species, 

 especially those of the groups of Cinnamomeae, Caro- 

 linae, and Gallic*, can be increased by root-cuttings; 

 the roots are taken up in fall, stored during the winter 

 in sphagnum or sand in a frost-proof room, and sown hi 

 spring in drills and covered about 2 inches deep. The 

 species of the last-named groups and some others are 

 also often increased by suckers and division. Budding 

 and grafting is less often done with the wild roses and 

 should be avoided for roses in shrubberies where the 

 individual plants cannot be carefully watched; the 

 stock usually throws up suckers and outgrows the 

 cion, often in a short time. For general notes on cul- 

 ture and varieties, see Rose. 



KEY TO THE GROUPS. 



(For a horticultural classification of roses, founded primarily 

 on garden values, see the article Rose. ) 



Subgenus HULTHEMIA. 



Lvs. simple, without stipules: fls. yellow. 



Section 1. SUCPLICIFOLI-E. Species No. 1 



Subgenus EUROSA. 

 LTS. pinnate stipulate. 



A. Styles exserted beyond the mouth of the receptacle. 

 B. Exserted styles connate into a column, usually as 

 long as stamens. (See Fig. 3434 right.) 



Section 2. SYSTYL.E. Species Nos. 2-10 

 BB. Exserted styles free, about half as long as sta- 

 mens: Ifls. usually 3-5. 



Section 3. INDICT. Species Xos. 1 1-14 

 AA. Styles reaching only the mouth of the receptacle and 

 stigmas forming a sessile head oter it (see Fig. 

 3434), but slightly exserted in Xos. 53 and 54- 

 B. Stipules fret or adnate only at the base, small: 

 sarmentose or climbing shrubs: fls. white or 

 yellow. 



189 



