THE PLANT GEOGRAPHY OF 

 THE LAKE OKOBOJI REGION: 

 ADDITIONAL NOTES 



By Bohumil Shimek 



Since the publication of the Bulletin on the flora of the Lake 

 Okoboji region^ two years ago, field studies have been continued 

 by several members of the staff of the Macbride Lakeside Lab- 

 oratory, and papers by Drs. Stephens and Wylie, and Mr. Stoner 

 which are a result of these studies, are included in this Bulletin. 



The writer continued his observations on plant distribution in 

 the lake region with some interesting results. 



The summers of 1915 and 1916 were unusual in their meteoro- 

 logical conditions. The season of 1915 was exceptionally cool 

 and moist, while that of 1916 was cool and moist in the spring, 

 but hot and rather dry during the summer. The greater abun- 

 dance of water rehabilitated many of the smaller kettleholes, 

 some of which had entirely lost their earlier character, and their 

 number is greater than is indicated in the forest map of the lake 

 region published in the Bulletin cited, which represents the 

 greater part of the kettleholes noticeable during the dry sum- 

 mers preceding that of 1914. ^ The greater amount of moisture 

 during these two years produced striking changes in the flora. 

 Swamp and low ground species became much more abundant, 

 and several species which are ordinarily found in low grounds 

 were observed on the higher prairie west of West Okoboji lake. 

 The most striking of the latter are the following, which may be 

 added in the former Bulletin to the column numbered in the 

 Prmrie list, pp. 29-37 : 



Iris versicolor L. Ill 



Eahenaria leucophcsa (Nutt.) Gray III 



^ Shimek, B. Bulletins from the Labs, of Nat. History, State Univ. of Iowa, vol. 

 VII, no. 2, May, 1915. 



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