118 ROSACEAE 



Prickles stout and strongly recurved R. palustris, p. 120 



Prickles slender and straight. 



Leaflet surfaces pubescent beneath. 



Leaflets thin R- Lyonii, p. 122 



Leaflets thick and coriaceous R. rudiuscula, p. 125 



Only the veins beneath pubescent. 



Leaflet teeth not gland tipped R. Carolina, p. 121 



Leaflet teeth gland tipped R. serrulata, p. 125 



Calyx lobes erect after flowering, and persistent. 

 Prickles generally absent below the stipules. 



Leaflets 9 to 11 per leaf, densely pubescent beneath 



R. suffulta, p. 127 



Leaflets 5 to 7 per leaf, finely pubescent beneath 



R. blanda, p. 124 



Prickles present below stipules; leaves glabrous 



R. Woodsii, p. 128 



ROSA SETIGERA Michaux 

 Prairie Rose 



The Prairie Rose, fig. 27, is a shrub with arching, climbing 

 stems usually 4 to 12 feet long, which are armed with prickles 

 scattered singly along and around the stem and in pairs below 

 each leaf on the upper part of the stem. They are recurved, 

 or rarely straight, and the lower half is much enlarged and 

 flattened laterally. Both petioles and rachises are more or less 

 covered with stalked glands. The stipules are narrow, adnate 

 for about three-fourths of their length, and marginally studded 

 with glandular hairs. Leaves on old stems generally have 3 

 leaflets, on new stems either 3 or 5 leaflets. The leaflets are 

 lanceolate to broadly ovate, or sometimes slightly obovate, and 

 lateral leaflets are nearly sessile. The terminal leaflet is defi- 

 nitely stalked and is always the largest, and the basal pair, 

 when there are 5 leaflets, is always much smaller. Leaflets 

 are wedge shaped or rounded at the base, or the terminal 

 leaflet sometimes may be subcordate, acute or acuminate at 

 the apex, either serrate or doubly serrate. The upper surface 

 is glabrous, and the lower surface is glabrous or somewhat 

 pubescent along the veins. 



The flowers, which appear from the middle of June through 

 July, are borne in terminal corymbs, on pedicels covered with 

 glandular hairs. The calyx tube and the sepals are glandular 

 hispid, the end of the sepals being reflexed after flowering and 

 later deciduous. The petal color is light to deep rose. The 



