Ontario Atv Trails

Why trees grow in some areas but not others?

My grandfather is 90 acres of bush behind his house and my family owns 200 in total. The property is covered by leafy trees in the Boreal Shield of Ontario. A system of ATV and snowmobile trails around at a time when I reached a clearing where the dense forest becomes a field of wildflowers is one acre in size. My question is: Why do not the trees surrounding the area to grow in this area, why not grow and why not get in on the cultivated field. In midfield there are several large trees in the center what causes them to grow while the rest of the field is barren. Whatever it is, makes a beautiful picture: http://img38.imageshack.us/ img38/7908/001oja.jpg

There could be an environmental condition (nutrients, soil composition, amount of moisture, temperature) that inhibits the growth of trees. Perhaps the field was exactly that, a field that has been cultivated over many years of maintenance of the trees under control. It seems that mature trees on the edge of the field of what could indicate the trees are beginning to invade the prairie.

Amphibious ATV trails & mud bog at Carolina Adventure World