Alvar

I have mentioned that the garden is on an alvar. However, I have never properly explained what an alvar is.

Wikipedia describes it as: " a biological environment based on a limestone plain with thin or no soil and, as a result, sparse grassland vegetation. Often flooded in the spring, and affected by drought in midsummer."

Here is what part of the alvar looks like at Roche fleurie. As you can see on the right, a stone pavement, just about as smooth as a concrete floor, which is crisscrossed by crevasses such as the one on the left.

One rare and a few not so rare

Sunday morning, I went, with my friend Elizabeth, to a conservation area, about 10 minutes from here, to see the annual display of a very rare daisy. Its common name is lakeside daisy (Tetraneuris herbacea) as it is found only in a few small colonies around the Great Lakes in Ontario, Ohio, Michigan and Illinois. It grows on a very thin layer of soil, directly on the alvar (limestone plain). Here is what it looks like.

Lakeside Daisy