History of the Limestone Barrens

The island of ______________ (D-7) is thought to be a product of the collision and separation of massive land masses called tectonic plates which float on the Earth's molten __________ (D-1). These land masses float around atop the mantle, moving with ____________ (A-17) in the molten rock which are caused by the heat of extreme pressure and radioactive decay. Where plates are forced together, mountains, earthquakes and volcanoes occur. Where the plates are now being pulled apart, the mantle is exposed and molten material comes out and forms a ridge along the crease.

The limestone barrens once was the __________ (A-11) of a shallow tropical sea. Over millions of years (470-480), during which life flourished in this sea, the _______ (D-15) of dead marine organisms piled up on the sea floor and solidified into limestone. This is why the barrens are full of calcium carbonate, the chemical that makes up shells. This is also why the barrens have many ________(D-14), mostly gastropods, trilobites and cephalopods.

Newfoundland was eventually formed by the collision of tectonic plates 350-400 million years ago. This is when the Appalachian __________(A-3) chain was formed and when the limestone sea floor was lifted above sea level.

The limestone was submerged again about 10,000 years ago by the tremendous weight of 1-3 km thick glaciers covering Newfoundland during the ice age. It re-emerged after the _______ (D-12) of the glaciers and glacial rebound is still ongoing. Glacial rebound is when a glacier moves away from an area and the tectonic _______ (A-16) which was previously weighed down into the mantle by the glacier begins to float back to the top. This process is still ongoing in Newfoundland and can be illustrated by the dropping sea levels around the ___________ (A-6).

In 1925 Merrit Lyndon Fernald, a _________ (A-18) from Harvard University, visited the Northern Peninsula and the limestone barrens. In that time he discovered many plants which we now consider rare, including the __________ (A-5) Long's Braya and the ___________ (D-8) Fernald's Braya. He also identified nine of the ___________(A-14) known Fernald's Braya sites. Long's Braya is named for a botanist who accompanied and assisted him on his trip.

Since then, studies have indicated that the biggest threat to these plants are __________ (A-13). We have put these plants at risk through quarrying and traditional activities, even though, in most cases, we did not know they even existed. That is why the Limestone Barrens ________ (D-2) Stewardship Program was created. Based upon the ________(D-4) of people like Sue Meades and local green teams, it was determined that these plants were at risk and that, although human activity had brought them to this point, local residents were unaware of their ____________(A-9) and needed to be educated about them, as well as their habitat, in order to ___________ (A-10) them from further harm.

© Limestone Barrens Habitat Stewardship Program