THE VEGETATION OF THE PENOBSCOT 

 BAY REGION, MAINE 



By ALBERT FREDERICK HILL 



Instructor in Botany and Assistant Curator of the 

 Botanical Collections, Yale University 



CONTENTS 



I. Introduction 307 



Location 307 



Physiography and Climate 307 



Previous Botanical AVork 3H 



Acknowledgements 311 



Nomenclature and Ecological Classification 312 



ii. i'llytogeographical relations of the penob- 



scot Bay Region 313 



III. The Climax Forest of the Penobscot Bay Re- 



gion 325 



IV. The Physiographic Formation-Complex of 



the Penobscot Bay Region 334 



A. PRIMARY FORMATIONS OF THE XERARCH 



AND MESARCH SERIES 334 



1. Formations of Ordinary Well-Drained Uplands 334 



a. Association-types of igneous rock outcrops 334 

 Rock surface association-type 335 

 Crevice association-type 335 

 Heath mat association-type 336 

 Coniferous forest association-type 339 



b. Association-types of sedimentary rock outcrops 347 



c. Association-types of uncompacted rocks 348 



2. Formations of Well-Drained Uplands Along 



Streams 352 



a. Association-types of boulder and flood plains 352 



3. Formations of Well-Drained Uplands Along the 



Seacoast 355 

 a. Association-types of eroding areas along the 



coast 356 



Association-types of rocky sea bluffs 35(j 



Association-types of headlands 360 

 Association-types of sea bluffs in uncompacted 



rocks 364 



Proceedings. P. S. N. H. Vol. Ill, 1923 



