Old man's beard in New Zealand facts for kids

Old man's beard (Clematis vitalba) is a climbing plant that causes big problems in New Zealand. It's known as an invasive plant, which means it's not native to New Zealand and spreads very quickly, harming the local plants and animals. This plant is considered an "unwanted organism" under a law called the Biosecurity Act 1993. This means it's against the law to sell it, move it around, or grow it.

How Old Man's Beard Spreads

Old man's beard was first brought to New Zealand as a garden plant before 1922. People thought it looked nice! But now, the Department of Conservation and other groups spend a lot of money trying to control it.

This plant spreads easily because its seeds are carried by the wind. The seeds have a fluffy part, like a dandelion, which helps them fly. They can stay on the vine all through winter. These seeds grow best in places where the ground has been disturbed, like along the edges of forests or streams, or in gaps where trees have fallen. They need a good amount of sunlight to start growing.

Why Old Man's Beard is a Problem

Old man's beard is a very strong climber. It grows over other plants and trees, covering them completely. When it forms a thick layer, it's like a blanket that blocks the sun from reaching the plants below. This means the native trees and plants can't get enough sunlight to grow and stay healthy. It also stops new seeds from growing on the ground, which hurts the natural variety of life, also known as biodiversity.

Controlling Old Man's Beard

People use different ways to get rid of old man's beard. One way is to remove it by hand, which is called mechanical removal. If the vines are big, they can be cut at the ground. Then, a special gel (a herbicide) is put on the cut part to stop them from growing back. Any loose vines must be picked up because they can start growing again if they touch the ground. Small plants can be pulled out of the ground completely.

Scientists have also tried using "biological control." This means using natural enemies, like insects or diseases, that only harm old man's beard and nothing else.

In the 1980s, the Department of Conservation ran a public campaign to teach people about the dangers of old man's beard. They even had a famous British nature expert, David Bellamy, help spread the word!