Photograph of a cross-sectional view of soil in a forest stand near Perrigo Lake, Ontario. Only the organic layer can be seen in this image. Large amounts of wooden debris can be seen on the forest floor. A metal ruler can be seen near the center of…

Photograph of a cross-sectional view of soil in a forest stand near Perrigo Lake, Ontario. The organic, topsoil and subsoil layers can clearly be seen. A metal ruler can be seen near the center of the image.

Budworm damage on red spruce. Black Brook, J.D.Irving.

Balsam woolly aphid damage on A. grandis. N.B adjacent hemlock. Shawinigan Division, Macmillan Bloedel.

Budworm damage on red spruce. Black Brook, J.D.Irving

Budworms eating on tips of white spruce. Black Brook, J.D.Irving.

Petawawa - PNre - normal and fastigiate form (grafts)

Phosphorus deficiency in jack pine at 25 days. Jack pine, 1+0, nutrient deficiency, phosphorus.

Phosphorus deficiency in seedling jack pine at 70 days from germination. Jack pine, 1+0, nutrient deficiency - phosphorus.

Phosphorus purpling in shoots of seedlings. White spruce, 2+0, nutrient deficiency, phosphorus.