Distribution in scandinavian waters
Maximum length: Knotted wrack can under certain circumstances
be over 2 m long, but normally is seldom longer than 0,3-1 m.
Appearance: The plant is quite slender, dense with belt like
torso pockets that branch irregularly. Along the whole of the branch
small air filled bladders are regularly situated. They are not situated
in pairs, but individually. The root is robust. Male
and female reproductive organs develope on different individuals.
Knotted wrack varies in colour, from yellow to olive-green. Compare
knotted wrack with bladder
Depth: From sea level to
a depth of about 2 m. Quite often, knotted wrack builds banks
and toothed wrack.
Environment: Found on cliffs
and large rocks that are wave protected, but where water exchange
is still good.
Misc: Have you noticed the strange marks on the plant pictured
above? These have probably been caused by a grazing periwinkle.
Classification: Knotted wrack is a member of the
brown algae group.