Silver fern

The silver fern is a beautiful plant known scientifically as Alsophila dealbata. It is a type of medium-sized tree fern that grows only in New Zealand, meaning it is found nowhere else in the world. People often recognize this fern by the shiny, silver-white color on the underside of its leaves, called fronds.

In New Zealand, the silver fern is more than just a plant. It is a symbol that represents the country. Both people living in New Zealand and those abroad often use the silver fern to show pride and connection to the nation. The fern also has special names in the Māori language, such as kaponga or ponga, which are used alongside the common names of silver fern, silver tree-fern, or simply ponga or punga.

Description

The silver fern can grow very tall, reaching up to 10 metres (33 feet) or more. Its leaves, called fronds, can be up to 3 metres (9.8 feet) long and 1 metre (3 feet 3 inches) wide. The underside of these leaves has a beautiful silver-white colour, especially when the fern is fully grown. Younger plants have a lighter, pale green colour instead. This silver colour makes the fern easy to see at night, so people sometimes lay the leaves along paths to light the way. The trunk of the fern is woody and can be up to 12 metres (39 feet) tall, covered in brown or white bases from old leaves.

Taxonomy

The silver fern was first described in 1786 by a German scientist named Georg Forster. He called it Polypodium dealbatum. Later, in 1801, another scientist named Olof Swartz moved it to a different group called Cyathea, naming it Cyathea dealbata. In 1970, a scientist named Rolla M. Tryon Jr. placed it in the group Alsophila and called it Alsophila tricolor.

Today, scientists disagree on the best name for this fern. Some prefer Alsophila dealbata, while others use Cyathea dealbata or Alsophila tricolor. This is because there was some confusion over which name should be used first. In 2025, it was settled that the silver fern has the right to use the name Alsophila dealbata because of an earlier reference made in 1838.

Georg Forster, Cyathea, Olof Swartz, Alsophila, Rolla M. Tryon Jr., William Colenso, Plants of the World Online, New Zealand Plant Conservation Network, Manaaki Whenua – Landcare Research, World Flora Online, Carl Borivoj Presl, Sphaeropteris glauca, August Carl Joseph Corda

Etymology

The name dealbata means "whitish" and describes the underside of the fern's leaves. In Māori, the fern is called ponga or punga. This word comes from languages spoken by people across the Pacific islands and is used to talk about tree ferns in general. In English, people usually say "punga" when they talk about these ferns. The Māori also have other names for it, like kaponga or kātote.

Habitat

The silver fern arrived in New Zealand during the Pliocene epoch, about 5 to 1.8 million years ago. It grows mainly on the main islands of New Zealand, but you won’t find it in the west and south parts of the South Island. It also lives on the Chatham Islands and Lord Howe Island, and has naturally grown in Ireland too.

This fern likes to grow in drier forest areas and open scrub lands. It can sometimes be found near the edges of bushes or in open spaces, even among rushes in sandy areas. Once it gets started, the silver fern can handle drier spots and grows best when it’s protected from wind and frost. It seems to do well in places where fires have happened before.

Traditional Māori culture

In traditional Māori culture, the silver fern, also called ponga, is a symbol of new life and growth. People used ponga trunks to build houses called whare, walls, and fences. The koru shape, which looks like a silver fern leaf unfolding, appears in many Māori artworks, such as carvings, designs at marae places, and traditional tattoos called tā moko. Old stories, known as Pūrākau, tell how the silver fern once lived in the sea. These stories also say that hunters would use the bright underside of the fern leaves to guide their way home at night, because the light from the moon would shine on them.

Modern uses

In New Zealand, ponga logs are often used in gardens. They help make walls to hold back soil and can also be used to mark the edges of garden beds.

As a symbol of New Zealand

The silver fern is one of New Zealand's most famous symbols. It was first used to represent the country during a football tour of Britain in 1888–89 and has since appeared on many products exported from New Zealand.

The silver fern was also used by New Zealand soldiers in wars and is engraved on the tombstones of New Zealand soldiers who died in battle. It appears on the country’s coat of arms, on some proposed flags, and is used by many organizations and political groups. The fern is also a popular symbol in sports, with many national teams using it on their uniforms.