﻿20 2 BOTANICAL GAZETTE [march 



the talus to get a good general view, and it may be said that the 

 presence of old logs upon the talus is an ecologic factor of con- 

 siderable importance, as these smaller Cladonias are usually 

 abundant on and about such decaying logs in favorable habitats. 



It is an interesting fact that such societies of the smaller 

 Cladonias are usually found in regions recently burned over, 

 while those containing the large Cladojiia ra7igiferina and its 

 allies are more common in regions not recently burned and con- 

 taining large conifers, especially pines. There is good evidence 

 that the Cladonia gracilis societies may become established in 

 soil-covered burned areas in ten or fifteen years, and the name, 

 Cladonia gracilis formation^ "^^-y be applied to other lichen 

 societies than those of the talus. Frequently, however, the less 

 conspicuous Cladoina cristatella or Cladonia verticillata predomi- 

 nates in these societies of the soil- covered areas. Finally, it is 

 reasonable to suppose that much longer time would be required 

 for such a plant society to become established upon the talus 

 than upon the soil. 



Cladonia rangiferifia and its allies are frequently seen wher- 

 ever conifers grow in the region, but nowhere else in such 

 abundance or luxuriance as on the shaded tali. Botanists have 

 frequently noted the fine Cladonias of Isle Royale in Lake 

 Superior eighteen miles east of Grand Portage, Minn. I have 

 riot seen Cladonias growing on tali on the island, but have 

 examined them somewhat under the conifers along the shore 

 line and have seen none equal in size to those of the tali 

 in the Sawteeth Mountains. The writer has studied these 

 somewhat carefully and has found them best developed at 

 Grand Portage and Grand Marais. The Cladonia rangiferi/ia 

 formation is best developed on the east side of Hat Point 

 near Grand Portage. The point is about one hundred rods 

 wide at the landward extremity and extends out into the lake 

 somewhat more than a mile, in a southeastward direction, 

 to a lakeward extremity which is only four or five rods wide. 

 To the landward end, Mount Josephine rises about 800 feet 

 above the lake, and from Mount Josephine to the lakeward 

 end the point gradually decreases in elevation as well as in 



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