Prunus 



Rosaceae 



579 



Jan. 



Feb. 



Mar. 



Apr. 



May 



June 



July 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



Miles 



50 



Map i|8l 



Rosa rudiuscula Greene 



Prunus lanata (Sudv 



50 

 Map 1183 



Mack. & Bush 



Flowers in racemes on branchlets of the present or previous year. 



Flowers (15) 20-30, on long racemes, appearing on branchlets of the present 

 season; sepals glandular; mature blades usually more than 5 cm long. 

 Leaf blades mostly obovate, thin, except in the variety, the margins sharply 

 serrate; sepals wider than long, deciduous. 

 Rachis of racemes, pedicels of flowers, branchlets, and lower surface of leaves 



glabrous 8. P. virginiana. 



Rachis of racemes, pedicels of flowers, branchlets, and lower surface of leaves 



pubescent, sometimes the branchlets nearly glabrous in autumn 



8a. P. virginiana var. demissa. 



Leaf blades elliptic or lanceolate, thicker than those of the preceding species, the 



margins crenate-serrate; sepals longer than wide, not deciduous 



9. P. serotina. 



Flowers 6-12, on short racemes, appearing on branchlets of the previous year; 

 leaf blades orbicular or orbicular-ovate, abruptly acute at the apex, generally 

 less than 5 cm long; sepals about 2 mm long, entire, glandless. . 10. P. Mahaleb. 



1. Prunus americana Marsh. American Plum. Map 1182. More or 

 less frequent throughout the state. It prefers moist soil and is commonly 

 found in open woodland along streams, about ponds and lakes, and in 

 moist, prairie habitats. In Indiana this tree rarely reaches a diameter 

 of 8 inches and is generally 2-5 inches in diameter. Its habit of sprouting 

 prolifically gives rise to our "plum thickets." 



Conn, to Mont., southw. to Fla., Tex., and Colo. 



2. Prunus lanata (Sudw.) Mack. & Bush. Woollyleaf Plum. Map 

 1183. Probably frequent in southwestern Indiana, and infrequent to rare 

 northward. The plums are not easy to identify, hence their collection may 

 be neglected. It is necessary to collect the flowers and mature fruit from 

 the same plant and this task is not as easy at it might seem. I have collected 

 flowers from many a shrub and tree and returned at fruiting time to find 

 that fruit had not developed. 



Ind. to Okla. and southw. to the Gulf. 



3. Prunus pumila L. Sand Cherry. Map 1184. Found only in the 

 northwestern part of the state in the counties shown on the map. It is 



