Southern Rata (Metrosideros umbellata)
Best suited to cooler, high rainfall regions this rata grows particularly along the South Island’s West Coast but is the most widely spread of all New Zealand rata ranging from small trees on high Northland and Coromandel outcrops to the subantarctic Auckland Islands where it forms the country’s southernmost forests.
Occurs from sea level to 760m.
Roots
Rata, like its relative, pohutukawa, has the ability to sprout root systems as and where needed. These adventitious roots form out of trunks and branches; and are able to grow in air over surfaces as they search for crevices, pockets of soil and moisture.
Wood
Dense and strong, as needed to withstand wind damage and drought; hard, very heavy, dark red heartwood; slow growing.
Bark
Rough and flaky forming a medium-thick, dry covering capable of protecting the tree from drought; and excellent surface for its own aerial roots and the roots of epiphytes (an epiphyte stores water for itself and its host).
Leaves and shoots
3-6 cm long. Leaf is sharply pointed.
Flower colour
Scarlet. Occasional white or yellow.
Flowers between December and February depending on location and weather patterns.
Stamen
Approximately 2cm.
Fruit/seed capsules
Largest capsule of the three, being around 0.75 - 1 cm per individual capsule. Up to 6 in a bunch. Bright green when young. Fruits require a year to mature.
Mature trees
Grows to around 15 m high or more, with a trunk diameter up to 1m, sometimes much larger, sometimes sprawling rather than upright.
Growth rate
Slow.
How old
Can reach 500 years old on glacial moraine.
Ecosystem
Plants:
Mainly beech forest, podocarps and kamahi.
Insects:
A major source of honey on the West Coast, several scale insect species on leaves.
Birds:
Nectar for kaka, tui and bellbird.
Animals:
Roosts for bats on southern islands.