An alvar is 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, alvars support a distinctive group of prairie-like plants. [1] .

Alvar is a grass- and sedge-dominated community, with scattered shrubs and sometimes trees. The community occurs on broad, flat expanses of calcareous bedrock (limestone or dolostone) covered by a thin veneer of mineral soil, often less than 25 cm deep.

Alvars are naturally open habitats with either a thin covering of soil or no soil over a base of limestone or dolostone. Their unique geologic and physical characteristics set the stage for natural communities that simply cannot exist elsewhere. Where are alvars found?

The 1,210-acre Maxton Plains Preserve protects the globally-significant alvar landscape and 10 Michigan state-rare plants, eight found in the alvars and two found in the forests. The alvars found on Drummond Island are the largest remaining high-quality alvars in North America.

Feb 12, 2012 · Alvars are open ecosystems on thin soil – or no soil at all – over a limestone base. These fascinating habitats are extremely rare globally. North America’s alvars, at least, what’s left of them, are mostly in Ontario.

Alvar ecosystems are grassland, savanna and sparsely vegetated rock barrens that develop on flat limestone or dolostone bedrock where soils are very shallow.

The Open Alvar Grasslands and Pavements category (Table 1) contains five different characteristic alvar communities. The characteristic communities under this category include: tufted hairgrass wet alvar grasslands, little bluestem alvar grasslands, annual alvar pavement-grasslands, alvar nonvascular pavements, and poverty grass dry alvar

Mar 5, 2014 · Alvar is the name used for a distinctive habitat formed by a thin covering of soil or no soil at all, over a base of limestone or dolostone bedrock. These alvars support specialized species communities and are found only in the North America Great Lakes Basin, Estonia, Sweden, Ireland and UK.

Some alvars on the Bruce Peninsula are home to arctic alpine plant species such as wild-chives, red anemone and alpine bluegrass. Other alvars have plants more typical of a grassland environment, such as prairie smoke, Indian paintbrush and False pennyroyal.

Overview: Alvar (alvar grassland) is a grass- and sedge-dominated community, with scattered shrubs and sometimes trees. Alvar occurs on broad, flat expanses of calcareous limestone or dolomite (dolostone) bedrock covered by a thin veneer of …