Oarweed

Laminaria digitata
  • Where it lives:

  • Non native species

About

Oarweed is a common kelp seaweed found in shallow seas around our coasts. They grow in dense kelp beds, attached to rocky seabeds using tough, root-like holdfasts. They grow at depths of up to 20m and the floating fronds may be exposed at low tide. Their holdfasts create a microhabitat for many small species - including worms, brittle stars and even sea spiders! So if you spot kelp washed up on the shore, look closely at the holdfast (looks like roots) and see if anything is inside! Oarweed's fronds are flat and split into finger-like sections, often resembling a hand. The stipe is very flexible, allowing it to bend right over on very low tides and stop the fronds from drying out. It also allows it to survive rough and stormy conditions.

How to identify

Oarweed is a typical 'kelp' seaweed, dark browny-green, with long fronds split into long 'fingers' or 'ribbons'.

Did you know?

Oarweed, also known as Tangleweed, has been used by humans for centuries for fertiliser, food and as a source of chemicals.

How people can help

Seaweeds provide a vital link in the food chain for many of our rarer species. The Wildlife Trusts are working with fishermen, researchers, politicians and local people towards a vision of 'Living Seas', where marine wildlife thrives. Do your bit for our Living Seas by supporting your local Wildlife Trust or checking out our Action pages.