ECOLOGICAL RELATIONS OF THE FLORA. 



49 



Gaylussacia haccata. 

 Helianthiis divaricatus. 

 Solidago juncea. 



Quadrats. 



Each plant has about 200 sq. cm., assuming even spacing. 



Dune Bushland Formation: This formation was not prominent at 

 Sand Point. In many places it was left out of the succession altogether. 

 The trees of the jack pine were able to develop in the Poa compressa 

 sod without the nurse agency of this formation. 



Where the bushland was developed Primus pumila, Cornus stolonijera 

 and Populus tremuloides were the principal species. The bush was 

 best developed on the inner side of the outer dune. 



The formation was not prevalent enough to lend itself to a grouping 

 into associations. 



Dune Forest Formation: In the typical dune forest formation the 

 predominating tree was Pinus hanksiana. The formation was open, 

 the trees averaging 15 to 20 feet apart. The floor stratum consisted 

 of persistent heaths and some other xerophytic species. Blueberries 

 were common and made their best growi;h here. In the open places 

 on Sand Point there was a very prominent sod of Poa compressa 

 and this sod association was very important in the succession, being 

 even more so than the heath mat, for in it were found seedlings of 

 Pinus resinosa and Pinus strohus. (Plate IV b.) 



Detail of the Jack Pine Association, 

 Dominant Species: 



Pinus hanksiana. 

 Sub-Dominant Species: 

 Pteris aquilina. 

 Pinus strobus. 



