The two adjacent estates have - until recent times - remained fairly intact, although parts have from time to time been leased for stone and timber. This dual ownership and consequent management is reflected in the present composition of the woodland.
The northern half of Leigh Woods
The northern half was historically managed as coppice with standards. Though this hasn’t been actively coppiced on a large scale for nearly 100 years.
Consequently, it now has a closed structure and a good proportion of old trees and dead wood. The canopy is dominated by mature and over-mature oak standards with younger ash, birch.
Old coppice stools of large outgrown oak, ash and small-leaved lime make up a significant proportion of the canopy. There is a varied understorey of coppice hazel with field maple, holly, dogwood, hawthorn, spindle, and guelder-rose. Where the soils are thinner, yew is locally dominant.
The southern half of Leigh Woods
The southern part was formerly wood pasture and many of the veteran pollards, predominately oaks, have survived. A survey of the National Nature Reserve (NNR) found just under 300 Old Pollards.
This area was historically part of the Ashton Court Estate, a Site of Special Scientific Interest (SSSI), to the west.
These two sites have one of the largest populations of veteran trees in the South West. The pollards are home to rare and uncommon wood decay fauna, while the woodland has a good mix of canopy species with areas of ash, beech, oak and occasional cherry, field maple and small-leaved lime.
There are also small but important areas of herb-rich limestone grassland which is notable for the presence of several rare and scarce plants.