THE NORTHERN HARDWOODS REGION 



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acreage. Tamarack, hemlock, and, in northern Vermont, arbor- 

 vitae and white spruce occasionally seed up the old fields; and 

 stands of white pine also rarely occur. It may seem strange 

 that, in a region so dominated by hardwoods as this one is, 



Fig. 94. — Old highway and field seeding up to spruce. 



pure stands of conifers should occur on the old fields, but their 

 presence is made possible by the change in seed-bed conditions. 

 In the absence of the thick layer of hardwood leaves, favorable 

 conditions for coniferous reproduction often exist on the old 

 fields. 



The type is only temporary for no pure stand of conifers can 

 maintain its existence in the region if the natural forces are left 

 undisturbed. As soon as openings appear in the stand, and 



