Cross-section of nodule on Alnus glandulosa showing infected cortical cells (actinomycetes?) stained red; central red tissue are the vascular elements.

Nodules from roots of Alnus glutinosa in Dorset area; n.b. scale

Nodules on roots of Alnus glutinosa from Dorset area; x10.

Comptonia peregrina plant in Plonski Forest; this is the plant which had the nodules shown in slide #210.

Mycelium of Phytophthora cinnamomi in W. Australia

Nodules of Comptonia peregrina N-fixing

View of same location as slides # 207 and 208 showing litter after snow has gone, n.b. the curling of the leaves and the exposure of of the surface of the Ah.

Same location as slide #207, but in March as snow is melting n.b. the litter layer of the forest floor.

Winter and snow cover at the Dunlap Observatory, Richmond Hill, the location of profile in slide #140

Blocky, angular structure in the B of Slide #140 at Dunlap Observatory, Richmond Hill.