Some are more tree-like and the most

spectacular of these is northern rata (above). A

seedling, geminating in the top of tall host trees

(like rimu or puriri), sends out roots that over

several decades grow to the ground, surround

the host and form a trunk. The underlying host

rots away leaving behind a hollow central cavity.

At the other end of the size

spectrum – we have a

number of epiphytic

orchids. Not large and

showy like tropical orchids

but small, hard to spot and

often sweetly scented.

Hangers onAn epiphyte

is a plant that grows on

another plant, using it for

physical support but not

as a source of nutrients.

Relationships in Nature

Nest epiphytes are the most obvious.

These can grow so big

and heavy that they crash

dangerously to the

ground, earning the

nickname ‘widowmakers’.

400 x 530mm

Relationships in Nature

Here’s an example - the

kereru eats the large

berries of trees like

tawa & puriri. The berries give the bird

energy and the hard seed

is pooped out along with a

little bit of fertiliser

allowing the seed to grow

into a new tree in a new

place. Clearly the plant

and the birds both benefit.Some fungi invade and can kill trees, but

others are more co-operative. These ‘good’

fungi bind to tree roots and get food in the

form of sugars from the host. The plant gets

more minerals because of the fungal activity in

the soil. Normally hidden underground, the

fungus ‘fruit’ (commonly a mushroom or

toadstool) pops up underneath the trees in

autumn. Beech trees & manuka

in particular have a very close relationship

with these mycorrhizal fungi.

Give & takeMutualism

or symbiosis is a ‘win-win’

situation between two

living things.

Birds, native bees, weta, geckos & bats

feed on nectar and help the

plant by transferring pollen

from flower to flower.

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Relationships in Nature

A one wayRelationship

Parasites are

plants or animals that

benefit by living in or on

another species to the

disadvantage of the host.

Cuckoos are well-known

brood parasites throughout

the world. That means they

invade and parasitise the

nests of other birds. Here in

New Zealand, the migratory

shining cuckoo lays its egg

in grey warbler nests. Once

hatched, the larger cuckoo

chick evicts any remaining

warbler eggs or chicks and is

then raised alone by the grey

warbler adults.

Photo: Project Manu

Eaten from withinUnderground the threads of a parasitic Isaria fungus devour the living cicada nymph from

within. Above ground we can see the fruiting

bodies which sprout out of the victim's head.

The powdery spores fall onto the forest floor

and may be eaten by another unlucky cicada

nymph, repeating the fungus life cycle.

Ph

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Kerr

Ph

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: An

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Ph

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Relationships in Nature

The kawakawa moth lays

its eggs on many plants

but mainly kawakawa

leaves like this one. The

eggs hatch and the

hard-to-spot nocturnal

caterpillars chew very

noticeable holes in the

leaves.

Who did this?

A kawakawacaterpillar!Life size

275 x 300mm

Relationships in Nature

What is this?A puriri caterpillars front door!A puriri caterpillar spends its first year

feeding on the forest floor but then

finds a tree (often a puriri) and bores a

hole in the trunk for its home. It covers

the entrance with a diamond-shaped

lid made of caterpillar silk and

sawdust. It chews away at the nice

fresh wood near the entrance and

grows big and fat before pupating

(this can take between 2 and 7 years!).

Their tunnels

later become

good homes for

tree weta.

The adult puriri moths

emerge in spring, live

only a few days and

during this time the

female lays about 2000

eggs on the forest floor.

400 x 380mm

Actual size!

Fact

Did you know?

Photo: Tony Wills

These are our largest

native moths -

females have a

wingspan up to

150 mm.