Eucalyptus hypolaena facts for kids

Eucalyptus hypolaena is a special type of tree or mallee (a small, bushy tree) that only grows in Western Australia. It has rough, dark grey bark near the bottom of its trunk and smooth bark higher up. Its leaves are shaped like spears, and its flowers are pale yellow. When it grows fruit, they look like small, round barrels.

What Does This Eucalyptus Look Like?

Eucalyptus hypolaena is a tree or mallee that can grow up to 15 meters (about 49 feet) tall. It has a special woody swelling at its base called a lignotuber, which helps it regrow after fires.

The bark on the lowest 2 to 3 meters (about 6 to 10 feet) of the trunk is rough, dark grey, and feels a bit like fiber or scales. Higher up, the bark is smooth and can be white, grey, or even pale pink.

Young plants and new shoots have stems that are somewhat square. Their leaves are dull, bluish-green (called glaucous), and can be 40 to 100 mm (about 1.5 to 4 inches) long and 20 to 40 mm (about 0.8 to 1.6 inches) wide.

Adult Leaves and Flowers

The adult leaves grow in an alternating pattern. They are shaped like spears, dull green on both sides, and measure 80 to 160 mm (about 3 to 6 inches) long and 13 to 30 mm (about 0.5 to 1.2 inches) wide. Each leaf has a stem called a petiole that is 20 to 30 mm (about 0.8 to 1.2 inches) long.

The flower buds grow in groups of seven where the leaves meet the stem (called axils). These groups are on a stalk called a peduncle, which is 5 to 13 mm (about 0.2 to 0.5 inches) long. Each individual bud has its own small stalk, or pedicel, which is 5 to 10 mm (about 0.2 to 0.4 inches) long.

Buds and Fruit

When the buds are ready, they are oval-shaped, 13 to 25 mm (about 0.5 to 1 inch) long and 6 to 8 mm (about 0.2 to 0.3 inches) wide. They have a beak or horn-shaped cap called an operculum, which is 7 to 18 mm (about 0.3 to 0.7 inches) long.

This eucalyptus usually flowers between May and September, producing pale yellow flowers. The fruit is a woody capsule that looks like a short sphere or a barrel. It is 7 to 10 mm (about 0.3 to 0.4 inches) long and 8 to 12 mm (about 0.3 to 0.5 inches) wide. The parts that open to release seeds (called valves) stick out quite a bit from the edge of the fruit.

How It Got Its Name

Eucalyptus hypolaena was officially described in 1999 by two botanists, Lawrie Johnson and Ken Hill. They published their findings in a science journal called Telopea.

The first plant they studied to describe this species was collected in 1983. It was found near the Trans-Australian Railway, about 57 km (about 35 miles) east of a place called Karonie.

Meaning of the Name

The second part of the plant's name, hypolaena, comes from ancient Greek words. "Hypo" means "under," and "(ch)laina" means "a cloak." This name refers to the hard bark that covers the bottom part of the tree's trunk, like a cloak.

Where Does This Eucalyptus Grow?

This mallee grows in special areas called mallee woodland. It prefers red, sandy soil that is a mix of sand and clay (called loam). It often grows alongside other eucalyptus trees, such as E. yilgarnensis and E. celastroides.

You can find Eucalyptus hypolaena to the east and north of Kalgoorlie. It also grows into the Great Victoria Desert in certain natural areas of Western Australia. These areas are known as the Coolgardie, Great Victoria Desert, and Murchison biogeographical regions.

Is It Endangered?

The Western Australian Government's Department of Parks and Wildlife has classified Eucalyptus hypolaena as "not threatened." This means that there are enough of these trees in the wild, and they are not currently at risk of disappearing.