62 COMMISSION OF CONSERVATION 



the young growth of the original species generally estabHshes itself, in 

 the course of twenty or thirty years, in their former numerical quanti- 

 ties. When, however, repeated fires occur, resulting in the destruction 

 of the seed trees, the young growth can invade the burned area only 

 from the margins of the unbiuned forest. With pines it is only accident- 

 ally that seeds are deposited more than 200 or 300 feet from the mother 

 tree, it would, therefore, require many generations of trees to advance 

 the new growth of the commercial species across a burned area a mile 

 wide. Areas of this size intervening between seed trees are very com- 

 mon on the old bums of the Trent valley. Therefore, to say nothing 

 of the disastrous effects of repeated fires upon the humus content of the 

 soil, repeated fires retard the natural re-establishment of valuable 

 species in their original proportions by several hundred years. 



The poplar-birch stands for the most part represent former pineries, 

 and they occur in the thin soils of the crystalline limestones and the gran- 

 itic rock, and upon the deeper soils of the sand plains and sand ridges. 

 The composition of these stands was determined in detail in several 

 representative places from township to township, with special reference 

 to the reproduction of the commercial species. 



Tudor. — The greater portion of Tudor township lying within the Trent water- 

 shed, some 14,400 acres, or 64 per cent of the area, was severely burned about 32 

 years ago. Various portions have been re-burned since, the most recent fire being in 

 1911. The most sterile conditions in this old burn are to be found along the crest 

 of the rocky ridge on the Hastings road about four miles from the village of Mill- 

 bridge, where not more than one-fourth of the area has soil of any kind, being com- 

 posed of ridges and hillocks of great blocks of rock. The poorer sites are occupied by 

 poplar saphngs and poles at the rate of only 150 per acre. On better sites, paper 

 birch occurs at the rate of 190, and sugar maple at the rate of 60 trees per acre, 

 while, at the foot of slopes and in deep ravines, one finds pure maple stands having 

 170 saplings and 240 poles per acre. The only reproduction of coniferous species 

 (balsam and cedar) is found aroimd the margins of swamps and in some of the deeper 

 ravines. 



North of Horseshoe lake and Jordan lake, where the country is made up of 

 low sandy or rocky ridges with swamps in the depressions, one finds on the burn of 

 about 32 years ago on the average acre the following : 



Number of Trees per Acre, Old Burn, Sandy Ridge 



Species — ■ Standards Poles Saphngs Total Per cent 



Poplar 10 90 360 460 56.1 



Sugar Maple .. ... 170 170 20.7 



Paper Birch .. ... 70 70 8.6 



Hop Hornbeam... .. ... 50 50 7.3 



Pin Cherry .. 20 40 60 6.1 



Balsam .. ... 10 10 1.2 



Total 10 110 700 820 100.0 



Percent 1.2 13.4 85.4 



