Ammophila (plant)

Ammophila is a genus of flowering plants with two or three similar types of grasses. Its name means "sand friend" in Greek because these grasses grow mostly on coastal dunes. People call them marram grass, bent grass, or beachgrass.

These grasses have special underground stems called rhizomes that help them stay strong in sandy, windy places. The rhizomes also help keep dunes stable and stop coastal erosion. Ammophila grasses naturally grow along the coasts of the North Atlantic Ocean, especially near the Great Lakes in North America.

Although these grasses grow near the sea, they do not like very salty soil but can handle some salt. Because they are good at building dunes, people have brought them to many new places. But in some of these areas, Ammophila grows too much and harms local plants and animals. People work to control these grasses using special treatments and machines.

Species

There are two main types of Ammophila grasses: A. arenaria and A. breviligulata.

• European marram grass or European beachgrass grows along the coasts of Europe, including Iceland, and parts of northwest Africa.
• American marram grass or American beachgrass grows along the coasts of eastern North America, including the shores of the Great Lakes.

Some scientists think there might be two more types, but this is not certain. One, called Purple marram, is a mix between A. arenaria and Calamagrostis epigejos, found in parts of northern Europe near the Baltic Sea. Another, Champlain beachgrass, looks very similar to A. breviligulata and grows around Lake Ontario and Lake Champlain.

Ecology

In Europe, Ammophila arenaria grows mainly along coastlines and is the most common plant on dunes. It helps build up dunes by catching blown sand and holding it in place with its strong roots. This grass is important where the sand is still moving.

Marram grass is linked with two types of coastal plants found in the British National Vegetation Classification. In areas with lots of moving sand, Ammophila is the main plant. In places with less sand moving, other plants like Festuca rubra (red fescue) become more common.

Uses

Marram grass is useful because it can grow in sandy places and help keep the sand in one spot. This makes it great for keeping coastal dunes and sandy shores stable. People have known about this since the late 1700s.

In places like the North Sea coast of Jutland, Denmark, people used marram grass for fuel, making roofs, and feeding animals after frost. However, using the grass sometimes caused sand to move and cover farmland. To stop this, laws were made in 1779 and 1792 to help protect the dunes.

In Newborough, Wales, women used marram grass to make mats, covers for haystacks, and brushes. The grass has also been used for making roofs in many seaside areas of the British Isles.

Adaptations

Marram grass is made to live in dry, sandy places where there is little water. It has special leaves that roll up to catch tiny bits of water vapor, helping the plant stay moist. The tiny openings on the leaves, called stomata, are hidden in little pits, which stops them from opening too wide and losing water. Inside the rolled leaves, there are also hairs that slow down the wind, helping the plant hold onto its water. A waxy coating on the leaves works like a shield to stop water from disappearing into the air.