Trees Outside of Woodland
The trees that grow outside woodland – in hedgerows, parkland, wood pasture, orchards and along roadsides – are one of the Suffolk landscape’s most important ecological components, supporting greater biodiversity per individual than almost any other habitat feature. A single ancient oak in good condition can support over 2,000 invertebrate species, and the associated communities of lichens, fungi, hole-nesting birds and bats that depend on veteran trees represent a lineage of ecological continuity that cannot be replicated by planting.
Suffolk’s parkland and wood pasture heritage is extraordinary. Staverton Park near Woodbridge, with its grove of ancient pollarded oaks and the associated “Thicks”, is one of the oldest and most important wood pasture sites in England, with some of its trees dating back to the medieval period. Helmingham Hall, Ickworth, and several other estate landscapes contain veteran tree assemblages of national significance, whose ecological value is rooted in the centuries-long continuity of open-grown, low-density tree cover that allows the progressive development of deadwood communities, bark-dwelling invertebrates, and the epiphytic lichens and fungi that are among the most sensitive indicators of habitat continuity.
The white-letter hairstreak (Satyrium w-album) is the assemblage’s flagship species, its dependence on elm making it a particular focus for conservation in Suffolk. Unlike most of England, where Dutch elm disease has all but eliminated large elms from the landscape, parts of Suffolk retain significant elm populations – in hedgerows, wood pasture and coastal scrub – giving the county a disproportionate importance for this butterfly’s survival. Traditional orchards, another component of this assemblage, support their own distinctive communities of fruit-tree specialists, including the noble chafer beetle and a suite of lichen species that require the rough, furrowed bark of old fruit trees and the veteran tree conditions that only develop in long-established orchards.
Key
Listed as a conservation priority in Suffolk’s Biodiversity Action Plan.
Identified as a key priority for recovery under Suffolk’s Local Nature Recovery Strategy.
Associated habitats
Veteran and ancient trees: Individual trees of great age or biological antiquity – whether in parkland, hedgerows, wood pasture or open ground – support communities of specialist organisms found in very few other habitats. The decaying heartwood, cavernous cavities, rough bark and veteran microhabitats of ancient trees provide irreplaceable niches for rare beetles, fungi, bats and lichens. Suffolk has a notable concentration of veteran trees associated with its historic parklands and wood pastures, and these individuals represent living ecological archives that cannot be replaced within any human timescale.
Hedgerow trees and isolated field trees: Trees growing within hedgerows or standing alone in the open landscape contribute significantly to the ecological connectivity and structural diversity of the farmed countryside. They provide nesting and roosting habitat for birds and bats, foraging resources for pollinators and other insects, and can act as stepping stones linking woodland blocks. As these trees age, they increasingly take on the character of veteran habitat, and their long-term retention within the landscape is essential for sustaining populations of species dependent on mature timber.
Urban greenspaces and parks: Public parks, recreation grounds and informal open land within towns and cities can provide important foraging, nesting and roosting habitat for wildlife, particularly where mature trees are present. These spaces also help connect isolated tree populations across the urban landscape, allowing species to move between sites. Sympathetic management – reducing mowing around tree bases, retaining dead wood and avoiding the removal of veteran specimens – increases their value considerably.
Image: Wood Pasture and Parkland veteran tree clump © Natural England/Hannah Rigden