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Parasitic plants
Mistletoe
The plants take root on branches, from seeds dropped by birds that eat mistletoe berries.
Dodder
Red flowers are the only part of this leafless parasite that is visible outside the cactus.
Cactus mistletoe
Mushroom-shaped flower stalks emerge from underground stems, which feed on the roots of host plants. Thin stems wrap around a host plant and weaken its immune system.
The pale stems of this plant are parasites of ivy plants.
Thurber’s stemsucker
Helosis
Most plants absorb water and nutrients from the soil to make their own food using energy from sunlight, but others have developed sneakier ways to survive. Parasitic plants pierce the stems or roots of other plants to steal their hard-earned supplies.
Ivy broomrape
Tiny flowers, 2 mm across, bloom along the host stem.
There are two main types of parasitic plants. Hemiparasites (half parasites) can use sunlight to make some of their own food but absorb water, nutrients, and sometimes sugars from the host plants they live on. Some hemiparasites, such as mistletoe and the Australian Christmas tree, will
Eyebright
This tiny wildflower relies on nutrients stolen from the roots of nearby grasses.
The corpse lily has the world’s largest flower, more than 3 1⁄4 ft (1 m) across.
The parasite steals nutrients from the roots of other plants to grow as tall as 14 in (35 cm).
Corpse lily
All parasitic plants have modified roots called haustoria, which enter the roots or stems of host plants to steal food, water, and nutrients.
Parasite
Host plant
The haustoria grow toward the chemical signals given off by the host’s roots. Parasitic plants
Au s t r a l ia n C hr is tm a s tree
The flowers of this plant look and smell like rotting meat.
This tree’s greedy roots can steal nutrients from plants 360 ft (110 m) away.
die if they cannot find a host to steal from. Others, including eyebright and butter and eggs, can survive without a host, although they tend to not grow as well. On the other hand, the second type, holoparasites (whole parasites), cannot make any food of their own and must find a host plant to survive. Some holoparasites, such as dodder, grow above ground. Most, such as the cactus mistletoe, Helosis, Thurber’s stemsucker, and the impressive corpse lily, live within their host plant, emerging only to flower. Parasitic plants do not generally kill their hosts but can weaken them.
More articles from this publication:
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 192
ACKNOWLEDGMENTS
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 184
PLANT INDEX
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 178
Plant science
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 188
INDEX
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 180
Space garden
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 182
GLOSSARY
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 176
Plants of the world
from Trees, Leaves, Flowers and Seeds A Visual Encyclopedia of the Plant Kingdom (Sarah Jose)
, page 172