Volume 13 Number 7 



The Plant World 



A Magazine of General Botany 

 JULY, 1910 



ROCKY MOUNTAIN RAMBLES. * 



By L. H. Pammel. 



Those who have done botanical collecting in the Mississippi 

 Valley, in a state like Iowa, have found that the floristic fea- 

 tures of the adjoining states do not differ essentially except 

 in some local particulars. There are no violent topographic 

 changes. The streams have carved their way through the dif- 

 ferent geologic formations, sometimes with a narrow flood plain, 

 as the Des Moines, or the flood plain is more ancient, as the ad- 

 jacent Skunk, which is but sixteen m.iles east from Boone. One 

 can only observe in a general way that some species are north 

 bound, as the svcamore {Platanus occidentalis) , which reaches 

 its northern limit along the skunk near Ames, although another 

 southern species, the buckeye (Aesculus glabra), does not occur 

 on this older stream in this vicinity, though abundant along the 

 Des Moines a little north of Boone, and again along the Iowa to 

 Hardin county, a little north of Marshalltown, and along with 

 it the cherry birch. Of the south bound species, two birches, 

 the paper birch {Betula papyrijera) and the cherry birch, are 

 remarkable, the former occurring along the Mississippi and its 

 tributaries in eastern Iowa south along that stream to a little 

 north of Clinton. 



The plants of the small prairie-like openings in Wisconsin 

 where my early botanical collecting was done, do not diff"er 

 essentially from those found on the prairies of Iowa. The same 

 Gentians, Liatris, Spiranthes, Aster multifloriis and .4. laevis 

 occur along the roadsides there, as in Iowa. The meadow sun- 

 flower {Helianthus grosseserratus) is abundant in the swales, as 



♦Published originally in "Horticulture," 1908-1909, re-arranged by the author for the 

 Plant Woiii.D. 



