Monday, July 6, 2009

Swimming off the Alvar

One of my favorite places to visit on the Marblehead peninsula is the alvar in front of my friend's home. An alvar is an extremely hostile environment for plant growth, being subjected to wind, storms, ice and relentless waves. These "limestone pavements" were named for their counterparts in Scandinavia, and they tend to host very unusual plant communities. This one is on the waterfront (like the preserve on Kelleys Island), while the Lakeside Daisy, Hyemonoxys herbacea is found on another alvar-like environment where the quarry operates inland Marblehead.

While swimming here, I noticed some of the pockets carved in the rocks were filled with decaying matter, like rotting sea-weed, or more correctly, lake-weed? This must become the foothold plants need to germinate on this otherwise impregnable limestone. Even the sides of these rock formations have dwarfed flowers, mosses and grasses hanging on for dear life. Plants here become Mother Nature's personal bonsai garden.

A dwarfed Erigeron clings tenaciously near the rock's edge.

It is a lovely place to drink in the beauty of the Erie islands, and if you don't mind sharing space with a few Northern Watersnakes- you can go for a swim. Just watch where you step, because the snakes were here first!


  1. Cheryl, yes, this is definitely a shoreline alvar. Very cool. This type of habitat would have probably graded inland to the LSD sites in a continuous but patchy alvar. Great LEWS pic. Since it isn't on an island, technically it isn't a LEWS under the federal endangered species act definition, but since it is not banded, it would qualify under the state listing as endangered. Interesting how that works, isn't it?


  2. Thanks for the snake-y comments Tom. I will leave that up to you and Janet to sort out!

    I'll stick to the swimming and botany.


  3. Hi Cheryl,
    That alvar looks very similar to the rock ledges of Bembridge Foreland (also of limestone) near me on the Isle of Wight. (No watersnakes here but we do get weaver fish buried in the sand which deliver a nasty sting.)

  4. I think I'll stay out of the water!

  5. I think I'll stay out of the water!