Do you know what an alvar is? Most people don’t, and I certainly didn’t until three and a half years ago when we heard a quarry expansion would probably destroy the alvar ridge we live on. Alvar is a Scandinavian word for a geological formation of flat, open areas of limestone bedrock where the soil is either shallow or absent. Due to extreme environmental conditions such as alternating flood and drought, unique and often rare plant, insect and bird habitats are formed.

Alvars are globally rare; most are centred around the Great Lakes of North America with a very few in Europe. Many alvars have already been destroyed by aggregate quarrying as the limestone is at or close to the surface and easy to access.

Overlooking the Ottawa River near Arnprior is the Braeside ridge, a little gem of an alvar, much of it in pristine, undisturbed condition. This alvar has a very rich plant community, much of which is at risk with either endangered, imperilled, vulnerable, regionally significant, or uncommon status. In fact the study of the alvar has only started recently, and been confined to a small area suggesting that there is much left to discover.

In addition to the rare plant community, this limestone ridge is a groundwater recharge area for regional aquifers, contains a deer wintering year, includes significant woodlands and supports significant wetlands!

Just to give you a taste of this alvar, lets talk about orchids. There’s something of a cachet about orchids, isn’t there? Well this is the home of rare orchids. In fact there are simply thousands of the vulnerable Ram’s-head Lady’s-slipper, Cypripedium arietinum, possibly one of the largest single population of this orchid on the globe. Then there’s the Hooker’s Orchid, Platanthera hookeri, (named for the man, not the noun), another vulnerable species and one I had the thrill of being the first to find on this alvar.

We want this alvar designated as Provincial Significant Wildlife Habitat to protect it for future generations rather than scraped off so the underlying rock can be turned into more roads and more buildings.

Contributed by Norma Moore of Arnprior Ontario

Photograph of Ram’s Head Lady’s Slipper by Norma Moore