Pterostylis paludosa facts for kids

The Swamp Greenhood (Pterostylis paludosa) is a special type of orchid that grows only in New Zealand. It's called a "greenhood" because its flower has a unique hood-like shape. This plant looks different depending on whether it's flowering or not. When it's not flowering, it has a small group of leaves close to the ground. But when it's ready to bloom, it grows a single flower on a tall stem with leaves along the stem. The flower itself is a beautiful see-through white with light green or yellowish-green stripes.

What Does the Swamp Greenhood Look Like?

The Swamp Greenhood is a plant that grows from an underground tuber (like a small potato). It's a perennial plant, meaning it lives for more than two years, and it's deciduous, so its leaves fall off at certain times.

Leaves and Stems

When the plant is not flowering, it has a group of two to four leaves on a short stalk. These leaves are long and narrow, about 25–60 mm (1–2 in) long and 7–11 mm (0.3–0.4 in) wide. They are pale green or yellowish-green.

When the plant is flowering, it doesn't have the group of leaves at the bottom. Instead, it grows a single flower on a tall stem that can be 80–900 mm (3–40 in) tall. This stem has three or four grass-like leaves, each about 24–26 mm (0.9–1 in) long and 7–11 mm (0.3–0.4 in) wide.

The Flower

The flower of the Swamp Greenhood is about 18–20 mm (0.7–0.8 in) long and 5–6 mm (0.20–0.24 in) wide. It's a see-through white with pale to yellowish-green stripes.

The top part of the flower is like a hood, called a "galea." This hood is made from the dorsal sepal (the top leaf-like part of the flower) and the petals (the colorful parts). The galea is puffy at the bottom and then quickly narrows to a pointed tip.

The side parts of the flower, called the lateral sepals, stand upright and touch the galea. They also have narrow tips that are slightly taller than the galea. Between these side parts, there's a small bulge with a V-shaped notch.

Inside the flower, there's a dark green part called the labellum. This labellum stands upright at its base and then curves sharply, sticking out above the V-shaped notch.

Swamp Greenhoods usually flower from September to January.

How it Got its Name

The Pterostylis paludosa was officially described in 1997 by three botanists: David Jones, Brian Molloy, and Mark Clements. They wrote about it in a magazine called The Orchadian.

The second part of its scientific name, paludosa, comes from a Latin word that means "boggy" or "marshy." This name perfectly describes where this orchid likes to grow!

Where it Lives

This special orchid loves sunny spots in wet areas like peat bogs and heathlands.

In New Zealand, you can find the Swamp Greenhood on the North Island from Great Barrier Island down to Waiouru. On the South Island, it mostly grows along the west coast, between Nelson and Westport. It also lives on Chatham Island.

Protecting the Swamp Greenhood

The Swamp Greenhood is currently listed as "at risk – declining." This means its numbers are going down, and it needs help to survive. The biggest problems for this orchid are:

• Wetland drainage: When wet areas where it grows are dried out for other uses.
• Changed fire regimes: Changes in how often and how intensely fires happen in its habitat.