Invasive trees in Whippendell Wood will be gradually reduced to increase light and promote new wildlife.

The woodland, which is owned and managed by Watford Borough Council and part of the Cassiobury Estate, will undergo a conservation project for five years.

The council said the woodlands has suffered from the growth of invasive, non-native trees over the past few years.

It will be working with Natural England, Forestry Commission and Woodland Trust to gradually remove those trees.

According to Cassiobury Park manager Pherenice Worsey-Buck, 60 percent of the 65 hectare area of woodland is classed as ancient woodland.

She said the council's forestry practice is based on the principle of continuous cover forestry (CCF) which means only certain trees will be selected for the thinning process.

This is to open space in the canopy of the woodland to provide the area below with more sunlight. Creating space will also help to establish the next generation of trees.

She said as the Cassiobury Estate declined so has the woodland, it has created dark woodland compartments with sheltered trees causing fewer ground flowers to grow.

Non-native species, including cherry laurel, snowberry and rhododendron, compete with native species and reduce the diversity of flowers.

She said: "We want to create an opening in the canopy. We are talking about the selective removal of one or two trees.

"With more light you can have other ground flora like blue bells which will start to grow and there will be open space for butterflies and small mammals."

She said older trees native to the woodlands will be protected. Diseased trees will also be removed to ensure the woodland is healthy.

Dead and decaying wood, such as fallen logs, will remain to support habitats for fungi and invertebrates.

She added: "We're aiming not to have trees of one size or one age but have layers of different ages. A healthy woodland needs to have a lot of different layers.

"We know that woodlands with a diverse age structure with lots of different species not only supports a greater amount of wildlife but also is more resilient to a changing climate and the challenges that brings.

"The focus of our woodland work is to improve biodiversity of the Cassiobury estate. We are constantly monitoring and gave great support from volunteers who love the woodland and the park as much as we do."

Ms Worsey-Buck said their work will help improve habitats and the conserving of veteran trees will support birds and bats.

She added: "I think having a woodland which is managed will make it look more cared for and can make people feel safer.

"We will also be working on signage with the county council for public roads and bridleways."

The team will also be working to improve the woodland entrances with signs, maps and information on the history of the area.