A PLANT that can grow through tarmac; an aggressive predator of water voles; a toxic plant standing up to five metres tall; and a plant with exploding seed capsules are all on Norfolk Wildlife Trust's latest wildlife survey - to map the county's alien wildlife invaders.

A PLANT that can grow through tarmac; an aggressive predator of water voles; a toxic plant standing up to five metres tall; and a plant with exploding seed capsules are all on Norfolk Wildlife Trust's latest wildlife survey - to map the county's alien wildlife invaders.

Local people are being asked to look out for these species and let them have details of their sightings - every single record counts. The species are:

American mink - originates from escaped animals imported for fur farms

Giant hogweed - can be dangerous to handle as the plant contains a toxic sap

Himalayan balsam - the seed capsules 'explode' flinging their seeds several metres

Japanese knotweed - all Japanese knotweed plants in the UK are female and probably derive from the same mother plant

Muntjac - Muntjac deer regularly visit gardens even in urban areas

NWT's wildlife and community officer Gemma Walker said: “This is a very interesting survey and gives people the opportunity to actively get involved in nature conservation.

“We believe it is really important to understand the extent to which these non-native species have spread in the county, because they can do harm.

“For example: invasive plants shade out the native plants, and when they die back often leave bare ground which is vulnerable to erosion, especially on river banks.

“The American mink is a veracious predator of water voles and plants such as Japanese knotweed can cause damage to buildings and hard structures.”

The Wildlife Invaders survey runs until the end of October is designed to find out where these species are found and what impact they are having the countryside.

It can be completed online at www.norfolkwildlifetrust.org.uk/naturalconnections or via a survey card, available by calling 01603 598333.

The trust is working with Norfolk Biodiversity Partnership and Norfolk Biodiversity Information Service to map the distribution of the five non-native species in the county.

These have been identified as having a potentially undesirable impact on native wildlife.