Cape York gum facts for kids

Eucalyptus brassiana, also known as the Cape York gum, is a special tree. People also call it gum-topped peppermint or karo in PNG. This tree is usually small to medium-sized. It grows naturally in northern Queensland, Australia, and in PNG.

The Cape York gum has interesting bark. Its trunk has rough, hard bark with cracks. Higher up on the branches, the bark is smooth and grey. Its adult leaves are long and narrow, shaped like a spear. The tree produces flower buds in groups of seven. When they open, the flowers are white. Later, it grows fruit that looks like a half-sphere or a cup.

What Does Eucalyptus brassiana Look Like?

Eucalyptus brassiana is a tree that usually grows to about 20 m (70 ft) tall. It has a special woody swelling at its base called a lignotuber. This helps the tree regrow if it gets damaged.

The bark on the lower part of the trunk is rough and hard. It's dark grey to black. Sometimes, this rough bark goes up onto the branches too. Higher up, the bark is smooth. It's grey over white or creamy yellow.

Leaves of the Cape York Gum

• Young plants have leaves that grow in opposite pairs.
• These young leaves are egg-shaped or broadly spear-shaped.
• They are 60–215 mm (2–8 in) long and 35–70 mm (1–3 in) wide.
• They have a dull green color.

Adult leaves are different.

• They are narrow and spear-shaped, often a bit curved.
• They measure 100–220 mm (3.9–8.7 in) long and 10–25 mm (0.4–1 in) wide.
• Each adult leaf has a stem called a petiole, which is 12–22 mm (0.47–0.87 in) long.
• Both sides of the adult leaves are shiny green.

Flowers and Fruit

The flower buds of Eucalyptus brassiana grow in groups of seven.

• Each group of buds sits on a main stalk called a peduncle, which is 10–22 mm (0.4–0.9 in) long.
• Each individual bud has its own small stalk, a pedicel, about 6–9 mm (0.2–0.4 in) long.

When the buds are ready, they are creamy yellow and oval-shaped.

• They are 10–15 mm (0.4–0.6 in) long and 4–7 mm (0.2–0.3 in) wide.
• The top part of the bud, called the operculum, looks like a cone or a horn. It's 8–10 mm (0.3–0.4 in) long.

The flowers themselves are white. After flowering, the tree produces fruit.

• The fruit is woody and shaped like a half-sphere or a cup.
• It is 4–10 mm (0.2–0.4 in) long and 7–12 mm (0.3–0.5 in) wide.
• The fruit has four or five parts, called valves, that stick out beyond its rim.

How Eucalyptus brassiana Got Its Name

The Eucalyptus brassiana was officially described for the first time in 1977. This description was made by a scientist named Stanley Thatcher Blake. He found a sample of the tree near Cooktown in 1958. His description was published in a science journal called Austrobaileya.

The second part of the tree's scientific name, brassiana, is a special honor. It was named after Leonard John Brass. He was another plant collector who gathered many plant samples on the Cape York Peninsula.

Where Does Eucalyptus brassiana Grow?

The Cape York gum grows in certain types of natural areas. You can find it in woodlands and open forests. It often grows in flat areas that get flooded during certain seasons. It also likes rocky slopes and gently rolling plains.

This tree is found on the north-eastern side of the Cape York Peninsula in Queensland. Its range extends as far south as Helenvale. You can also find Eucalyptus brassiana growing in the south-western part of Papua New Guinea.