Page 253 - (DK) Ocean - The Definitive Visual Guide

FLOWERING PLANTS 251

ORDER NAJADALES ORDER HYDROCHARITALES ORDER POALES through loose sand, and upright shoots
develop regularly along their length.
Neptune Grass Paddle Weed Marram Grass When the tangle of stems and leaves
impede onshore breezes, sand carried
Posidonia oceanica Halophilia ovalis Ammophila arenaria in the wind is deposited. Progressively,
TYPE TYPE TYPE the sand builds up, the stems grow up
Perennial Perennial Perennial through the sand, and a sand dune is
HEIGHT HEIGHT HEIGHT formed. In dry weather, the leaves curl
12 in (30 cm) 2 1 / 2 in (6 cm) 1 1 / 2–4ft (0.5–1.2 m) into a tube. The underside of the leaf
HABITAT HABITAT HABITAT then forms the outer surface and its
Rocks and sand Sand Coastal sand dunes waxy coating helps to reduce water
DISTRIBUTION Mediterranean DISTRIBUTION Coasts of Florida, USA, East Africa, DISTRIBUTION Western Europe and Mediterranean loss from the plant. Marram grass
Southeast Asia, Australia, and Pacific islands (natural occurrence); introduced elsewhere is widely planted to stabilize eroded
Neptune grass (also known as dunes, and has been introduced for
Mediterranean tapeweed) forms Marram grass is a tall, spiky grass this purpose to North America (where
meadows from shallow water to a that plays a key role in binding coastal it is known as European beach grass),
depth of 150 ft (45 m) in the clearest sand and building sand dunes. Its Chile, South Africa, Australia, and
waters. It grows on both rock and underground stems (rhizomes) spread New Zealand.
sand, has a tough, fibrous base, and
persistent rhizomes (stems) that grow
both horizontally and vertically. These
build up into a structure known as
“matte,” which can be several meters
high and thousands of years old.
Around the island of Ischia, Italy, more
than 800 species have been associated Members of the genus Halophila look
with Neptune grass beds. quite unlike other seagrasses, having
small, oval leaves that are borne on a
thin leaf stalk. As its scientific name
indicates, paddle weed is particularly
tolerant of high salinities (halophila
means “salt-loving”). Pollination takes
place underwater, and the tiny, oval
pollen grains are released in chains,
which assemble into rafts like floating
feathers. This is thought to increase
the chances of pollination of a female
flower. Despite its small size, paddle
weed is an important food for the
dugong (see p.419). An adult can eat
more than 88 lb (40 kg) of it a day.

ORDER CARYOPHYLLALES
Common Glasswort
Glasswort, also known as
marsh samphire, is an early
Salicornia europaea
TYPE Annual colonizer of the lower levels of salt
marshes and mudflats, where plants thick, waxy skin. It is able to prevent produce an ash rich in soda (impure
HEIGHT 4–12 in
(10–30 cm) are inundated twice a day by the tide. the salt absorbed through its roots sodium carbonate). The ash was then
It is a small, cactuslike plant with from doing any damage by locking baked and fused with sand to make
HABITAT Coastal
mudflats and salt bright green stems that later turn red. it away in vacuoles (small cavities) crude glass—hence its common name. OCEAN LIFE
marshes The tiny flowers and scale-like leaves within its cells. The plant stores water Glasswort can also be eaten boiled or
DISTRIBUTION Coasts of western and eastern North are sunk into depressions in the fleshy inside its succulent stems, hence its pickled in vinegar. It has a mild, salty
America, western Europe, and Mediterranean stem. Glasswort is protected externally cactuslike shape. For centuries, flavor, and is also known as poor man’s
from salt water and moisture loss by a glasswort was gathered and burnt to asparagus.