Lichen community ecology exercise

[Christine Maxwell]

Hello plant-edders
A colleague of mine is teaching a second year ecology course and is
looking for an exercise involving the community ecology of lichens,
which could be carried out in the fall or winter months in Ontario.
I am aware of one exercise that involves measuring and determining the
age of lichens on tombstones, but has anybody got any other ideas?
Any help would be appreciated.
Christine

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