Apocynum 



APOCYNACEAE 



763 



50 



Map 1636 

 Apocynum medium vary 

 sarniense (Greene) Woodson 



2. Apocynum medium Greene. 1 Map 1635. Moist places in open wood- 

 land, along roadsides, and in prairie habitats. 



N. B. to Fla., westw. to Que., Iowa, Nebr., and Tex. 



2a. Apocynum medium var. sarniense (Greene) Woodson. Map 1636. 

 Habitat that of the species. 



Woodson says : "Apparently a spontaneous variety, collected in sw. Ont., 

 se. Mich., n. Ind., and s. B. C." 



2b. Apocynum medium var. leuconeuron (Greene) Woodson. Map 

 1637. Habitat similar to that of the species. 

 Woodson says : "Upper Miss. Valley, eastw. to s. Mich, and n. Ind." 



3. Apocynum cannabinum L. Hemp Dogbane. Map 1638. In moist or 

 dry situations in almost all kinds of soils in all parts of the state. It is 

 usually found in small colonies along roadsides and fences, in hayfields, 

 fallow fields, and open woodland. I have found specimens of this and other 

 species of the genus growing in adverse ecological conditions, that have 

 much reduced leaves and a decumbent habit. I refer to such habitats as 

 ballast of railroads, gravel pits, and gravel bars of streams. 



Woodson says: "Generally throughout the eastern half of the U. S." 



3a. Apocynum cannabinum var. pubescens (Mitchell) A. DC. Map 

 1639. Found in habitats and places similar to those of the species. Infre- 

 quent. 



Woodson says: "Generally throughout the southeastern and central 

 U. S., in north-central Calif. ; also in s. Ont." 



1 After the text of this genus was written, Anderson writes that this species is a 

 fertile hybrid betwten Apocynum androsaemifolium and Apocynum cannabinum. 

 See Anderson. An experimental study of hybridization in the genus Apocynum. Ann. 

 Missouri Bot. Gard. 23: 159-168. 1936. 



