The arboretum has been working with St Nick’s Nature Reserve in York and the Species Recovery Trust to establish a tansy beetle ark site here at the arboretum.
The tansy beetle, Chrysolina graminis, is a nationally rare small bright metallic green leaf beetle. Its main habitat is on the banks of the River Ouse in York with smaller populations found on fenland in Cambridgeshire.
Work is ongoing to establish populations in suitable places in Yorkshire to help ensure the survival of this beetle.
The beetles date back to as early as the Neolithic period and are dependent on one main source of food, the tansy plant Tanacetum vulgare. Their numbers have dropped as their habitat is threatened and when the plant dies, they walk to find new ones as they rarely fly.
To help establish an ark site the arboretum team have been planting large numbers of tansy plants by the lake. They are an aromatic plant that grows in rough grassland, riverbanks and verges. It has button like yellow flower heads. Tansy was first used by the ancient Greeks as a medicinal herb and was known to grow in Charlemagne’s garden in the 8th century. It has a range of uses in medicine and cooking.
Once the plants have established themselves a small population of beetles will be introduced in the hope that they multiple and establish themselves here.
