ACTION is needed to help reverse the decline of many of Britain's best-loved woodland flowers, including the primrose, the nation's most extensive ecological woodland survey has found.

The study, Long-term Ecological Change in British Woodland (1971-2001), found the number of plant species in 1,648 specific plots in 103 native woods had declined by more than a third in 30 years.

Characteristic woodland plants like yellow archangel and sanicle fared worst, with 56 out of the 72 species becoming significantly less common.

Fifteen species of tree and shrub also showed decline in numbers, along with a general fall in tree seedlings, though holly bucked the trend by spreading abundantly in many woods.

On a visit to the Wyre Forest Visitor Centre, biodiversity and forestry minister Jim Knight said: "New policies for ancient woodland will help address the decline by promoting sensitive management of native and ancient woodlands to prevent problems like over-shading."

He said other agri-environment schemes and Forestry Commission initiatives, including reducing non-native trees and controlling livestock grazing in woodland, would help reverse the decline in woodland wildflowers.