AZ Arboretums

Eucalyptus microtheca

Coolibah

Common: Coolibah, Flooded box, Tiny capsule eucalyptus
Family: Myrtaceae
Origin: Native to Australia
Sunset Zones: 5, 6, 8-24
Light: Full sun
Soil: Widely tolerant
Water: Deep periodic irrigation for young plants until established.

Most widely planted non-native evergreen tree in Arizona. Hardiest of eucalypts. Picturesque. Strong looking, strong growing tree. Suitable for wind break. cleaner and less likely to break in the wind than many of the other eucalpts.

Bushy crown, vertical in youth, rounded in age. May have one or many trunks. Fast to moderate growth to 35-40 feet. Leans at 45 degree angle. Light gray-green and ribbony, on pendulous branches. Young trees have smooth and mottled white to gray trunks; older trees have wrinkled, cracked, fibrous bark. Inconspicuous white flowers. Tiny seed capsules in clusters of 3-5 do not litter.

This tall tree, featured in the song "Waltzing Matilda," produces one of the hardest and strongest timbers in the world. The wood is difficult to work with, however, because of the interlocking grain. Unsuitable for construction, it makes durable poles and fence posts. Aborigines obtained water from the superficial roots, by cutting forearm-sized root segments, then holding them vertically, after debarking