8o FOREST commissioner's REPORT. 



EFFECT OF FIRES AND CLEARINGS. 



The abundance of paper birch throughout this entire region 

 is due to fires, and in many cases the boundaries of the region 

 correspond exactly with the boundaries of these fires. So inti- 

 mate is this relation between paper birch and cleared or burned- 

 over areas that it is fairly safe to assume that areas containing 

 a good stand of birch have either been burned or previously 

 cultivated. The reverse, however, is not always true; burned 

 areas are not always occupied by paper birch. Aspen is equally 

 quick to seize upon them, white pipe is more or less character- 

 istic of such situations, and still other species may occupy them, 

 though less frequently. Paper birch readily occupies burned or 

 cleared areas, because its seeds are produced abundantly each 

 year and are easily carried to great distances by the w'ind, .so 

 that they are always on hand to restock open areas. The bare 

 mineral soil exposed by burns offers an ideal germinating bed, 

 and the full light gives the young seedlings an excellent chance 

 to develop without danger of being shaded out. 



.The greatest fire known in Maine occurred in October, 1825. 

 This is generally called the "Mirimichi fire," although it was 

 quite distinct from the famous fire of that name which occurred 

 in New Brunswick the same year. It covered in the neighbor- 

 hood of 1,300 square miles, and burned over practically all of 

 the area shown on the map from ]\Ionson and Abbott East to 

 the Penobscot River. This area now contains some of the heav- 

 iest and best stands of birch in the State. The irregular de- 

 tached section to the north is the result of two fires. The upper 

 part was burned over in 1837, and the lower at some time be- 

 tween this and the great conflagration of 1825. This section, 

 too, contains manv excellent stands of birch which are now 

 yielding valuable lumber. 



East of the Penobscot River is a large area in Hancock and 

 Washington counties, shown by vertical lines on the map, which 

 is intermediate in character, and its inclusion in the birch region 

 might be questioned. This land has practically all been burned 

 over, parts of it several times. In places it is still barren, while 

 in other places there is good second growth composed of a mix- 

 ture of many species. Paper birch grows throughout the area, 

 but not so generally in the pure stands that are characteristic 

 of it on other burns to the west. Here the white, or gray birch 



