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Home , Dark green fritillary, Gatekeeper (butterfly), Grayling (butterfly), Large tortoiseshell, Small heath (butterfly)

Woodland of concern

Woodland of concern: habitat features and principal foodplants

Woodland butterflies of concern

Principal foodplants

Species Woodland primary habitat Woodland secondary habitat Field layer Shrub layer Canopy layer and understorey Closed canopy Rides Clearings within woodland Woodland edge in woodland in woodlands

Chequered Skipper • • • • • Purple Moor-grass Dingy Skipper • • • • • Common Bird’s-foot-trefoil and Greater Bird’s-foot-trefoil Grizzled Skipper • • • • • A variety of plants from the Rosaceae , mainly Agrimony, Creeping Cinquefoil and Wild Strawberry Wood White • • • • • Legumes, especially Vetchling, Common Bird’s- foot-trefoil and Greater Bird’s-foot-trefoil Brown Hairstreak • • • • • Blackthorn and occasionally Wild Plum White-letter Hairstreak • • • • • • • English and Wych Elm Black Hairstreak • • • • • Blackthorn and occasionally Wild Plum Duke of Burgundy • • * • • Primrose and Cowslip White Admiral • • • • • Honeysuckle Purple Emperor • • • • • Sallows Small Pearl-bordered • • • • • • Common Dog-violet and Fritillary Marsh Violet Pearl-bordered Fritillary • • • • • Common Dog-violet and * occasionally other violet • • • • • Common Dog-violet and Hairy Violet Silver-washed Fritillary • • • • • • Common Dog-violet Heath Fritillary • • • Common Cow- and * occasionally Foxglove

* These species can breed in ride edges, but only where they are associated with regular clearings. Ride management alone is not sufficient to maintain their populations.

40 | Woodland management for butterflies and moths Other butterflies using woodlands

Species Conservation concern Woodland primary habitat Woodland secondary habitat Field layer Shrub layer Canopy layer and understorey Closed canopy Clearings within woodland Rides and woodland edge Bracken in woodland Principal foodplants in woodlands

Small Skipper • • • Grasses Essex Skipper • • • • Grasses Large Skipper • • • • Grasses Brimstone • • • • Buckthorn and Alder Buckthorn Large White • • • • Crucifers Small White • • • • Crucifers Green-veined White • • • • Crucifers Orange-tip • • • • Cuckooflower and Garlic Mustard Green Hairstreak • • • • • A wide variety of herbs and shrubs Purple Hairstreak • • • Deciduous oaks Small Copper • • • • Docks and sorrels Small Blue • • • • • Kidney Vetch Brown Argus • • • • Common Rock-rose, Common Stork’s-bill and Dove’s-foot Cranesbill Northern Brown Argus • • • • • Common Rock-rose Common Blue • • • • Bird’s-foot-trefoils and Black Medick Holly Blue • • • • Holly, Ivy, Dogwood, Spindle and other herbs and shrubs Red Admiral • • • • Nettles Painted Lady • • • • Thistles • • • • Nettles Large Tortoiseshell • • • • • • and sallows Peacock • • • • Nettles Comma • • • • • Elm, hop and nettles Dark Green Fritillary • • • • • Violets Marsh Fritillary • • • • • Devil’s-bit Scabious Speckled Wood • • • • Grasses Wall • • • • • Grasses Scotch Argus • • • • Grasses Marbled White • • • • Grasses Grayling • • • • • Grasses • • • • Grasses • • • • Grasses • • • • • Grasses Ringlet • • • • Grasses

Woodland management for butterflies and moths | 41 Woodland moths of concern

Species UK conservation status Woodland primary habitat Woodland secondary habitat Field layer Shrub layer Canopy layer and understorey Closed canopy Rides Clearings within woodland Woodland edge Veteran trees Bracken in woodland Principal foodplants in woodlands

Lampronia capitella Nb • • Currant and Gooseberry Goat Moth Nb • • • Living wood of deciduous trees Nemapogon picarella pRDB1 • • • Bracket fungus Phyllonorycter sagitella pRDB1 • • Aspen Coleophora tricolor None • • • • Basil Thyme Coleophora wockeella pRDB2 • • • • Betony Aplota palpella pRDB1 • • • Mosses Anania funebris Na • • • • Goldenrod Sciota hostilis pRDB1 • • Aspen False Mocha Local • • Pedunculate Oak Netted Carpet pRDB2 • • • • Touch-me-not Balsam Barberry Carpet pRDB1 • • • • Barberry Argent & Sable Nb • • • • • Birches, occasionally Alder and sallows Grey Carpet pRDB3 • • • • Flixweed Drab Looper Nb • • • • • Wood Spurge Barred Tooth-striped Na • • • • • Wild Privet and Ash Dark Bordered Beauty pRDB3 • • • Aspen and Creeping Sloe Carpet Nb • • • • Blackthorn Scarce Vapourer pRDB2 • • Various deciduous trees and shrubs Lunar Yellow Underwing Nb • • • • Grasses Cousin German pRDB3 • • • Bilberry and Heather, birches and Eared Willow Orange Upperwing pRDB1* • • Pedunculate and Sessile Oak Heart Moth pRDB3 • • • Pedunculate Oak White-spotted Pinion Na • • English Elm and Wych Elm Concolorous pRDB3 • • • • Purple Small-reed and Wood Small-reed Light Crimson Underwing pRDB3 • • • Pedunculate Oak Dark Crimson Underwing pRDB2 • • • Pedunculate Oak Common Fan-foot Na • • • Pedunculate Oak Clay Fan-foot Na • • Oaks Olive Crescent pRDB3 • • Oaks, Beech and occasionally other deciduous trees * May be extinct

RDB - Red Data Book species: species that meet the criteria of the British Red Data Book for (Shirt, 1987) RDB 1 - species categorised as Endangered RDB 2 - species categorised as Vulnerable RDB 3 - species categorised as Rare pRDB - proposed for inclusion in future Red Data Book listings Na - Nationally Scarce and recorded from 16-30 10km squares in Nb - Nationally Scarce and recorded from 31-100 10km squares in Great Britain *may be extinct

42 | Woodland management for butterflies and moths species accounts Distribution maps are based on Butterfly Conservation data from 2005-2009. Life cycle charts show approximate timings, which vary from year to year (with partial 2nd generation in light shading). Chequered Skipper

Principal foodplants in woodlands

Currant and Gooseberry Keith Warmington Living wood of deciduous trees Bracket fungus Aspen Basil Thyme Betony Mosses Goldenrod Aspen Pedunculate Oak J F M A M J J A S O N D Touch-me-not Balsam Egg Barberry Chrysalis Adult Birches, occasionally Alder and sallows Flixweed Population structure sunny, sheltered locations is crucial paths and rides (25-30m wide) and Wood Spurge for the adults. maintain glades (25-30m across). At Found in low density colonies that Wild Privet and Ash larger sites this clearance should be are spread over large areas. Females carried out over a number of years Aspen and Creeping Willow can move 1 to 2km between Habitat management to produce open spaces at different sources and breeding sites through The precise habitat requirements are Blackthorn stages of succession. Ideally rides open woodland and moorland. Long- not fully understood, but the following Various deciduous trees and shrubs and paths should run east-west to term survival, as with many other approaches are recommended: create a warm south-facing edge. Grasses species, is more likely if sites are Adding scalloped bays (c. 25m Bilberry and Heather, birches and Eared Willow linked, enabling dispersal between Grazed sites: Light deer or livestock across) at intervals along ride edges neighbouring colonies. browsing is important to prevent Pedunculate and Sessile Oak encroaching scrub shading out nectar will create additional sheltered Pedunculate Oak Foodplants plants, and populations have declined habitat. English Elm and Wych Elm where deer and livestock have been In , the main larval foodplant excluded. Although light grazing, Purple Small-reed and Wood Small-reed is Purple Moor-grass. especially in autumn/winter, maintains Pedunculate Oak flower-rich areas, high intensity Jim Asher Pedunculate Oak Woodland habitats grazing (particularly by sheep in Pedunculate Oak It is associated with the edges of the spring) can be damaging. The damp woodlands, or open spaces spend most of their lives Oaks within them, usually below 200m. high-up on the foodplant, so summer Oaks, Beech and occasionally other deciduous trees Favoured sites are on the edges of livestock grazing can remove food open broadleaved woodland where supplies together with the caterpillars richer soils produce tall growth of themselves. However, breeding Purple Moor-grass, typically with habitat usually occupies wetter areas scattered Bog-myrtle, Bracken and which sheep generally avoid unless birch scrub. Many colonies now stocking levels are high. survive only in wayleave habitats under power-lines. The adults and Ungrazed sites: A 7-10 year caterpillars have different habitat cyclical clearance of scrub beneath Damp grassy woodland alongside streams provides important habitat for Chequered requirements and at many sites wayleaves seems to benefit the Skipper their habitats occur as a mosaic. butterfly, and similar management Maintenance of flower-rich areas in should be used at under-grazed sites. Provide additional open space along

Woodland management for butterflies and moths | 43 Dingy Skipper Mick Sinden

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management Grazing: The most suitable grazing regimes are those that produce a The Dingy Skipper occurs in discrete The aim is to maintain a sparse range of sward heights including colonies, many of which are very sward interspersed with plenty of patches of less than 5cm height. small and consist of fewer than bare ground but some areas of tall Cattle grazing is preferred to sheep 50 adults at the peak of the flight vegetation should be retained. Sites grazing as it results in a less uniform period. It is a sedentary species that need not be large if high quality sward. Late spring or early summer is unlikely to colonise new areas habitat is present and other habitats grazing should be avoided, as egg- of habitat unless they are close occur nearby. laying Dingy Skippers generally avoid to existing populations. However, damaged foodplants. observations of natural colonisations Coppicing: A regular cutting sequence of woodland blocks reveal that a few individuals may Mowing: Mowing is always a poor in close proximity will ensure move several kilometres. alternative to grazing, but where rapid colonisation of new habitat, grazing is impractical, a single annual particularly where open rides permit Foodplants cut in the autumn can maintain Dingy movement between clearings. Ideal Common Bird’s-foot-trefoil is the Skipper sites. Mow on rotation so that conditions are provided in woodland usual foodplant in all habitats. some areas are left uncut each year. regrowth a few years after clearance, Horseshoe Vetch is also used on Remove cuttings from the site. when sheltered areas develop calcareous soils and Greater Bird’s- between coppice stools. On thin soils foot-trefoil on heavier soils. Scrub control: Periodic scrub or where deer browsing delays initial removal may be necessary at regrowth these microhabitats can be Woodland habitats some sites although some light, prolonged for several seasons. well-spaced scrub can provide Dingy Skippers occur in a wide range valuable shelter, especially on more Ride management: A network of of habitats in addition to woodland. exposed sites. Scrub can be cut on a open, sunny rides and glades is In woodlands, open sunny areas in rotation of 10 to 15 years to maintain beneficial and may be essential to rides and clearings are used. Suitable existing levels of cover. Where scrub link clearings in high forest woodland. conditions occur where foodplants reduction is necessary, stumps Open rides can be maintained by grow in a sparse sward, often with should be treated with herbicide to short-rotation coppice (5 to 8 years), patches of bare ground in a sunny, prevent regrowth. sheltered situation. Taller vegetation cutting back the woodland edge to is also required for shelter and 5 to 8m depending on the vigour of roosting. regrowth.

44 | Woodland management for butterflies and moths Grizzled Skipper Jim Asher

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Woodland habitats Coppicing: Cutting a regular sequence of woodland blocks in Grizzled Skipper populations are Grizzled Skippers occur in a close proximity will increase the influenced by a number of factors, wide range of habitats including chances of new habitat being including the size and quality of woodlands. Woodland rides, glades colonised, particularly where open habitat patches and the structure of and clearings where the larval rides permit movement between surrounding vegetation. In optimal foodplants grow in open but sheltered clearings. Ideal conditions are habitats with high foodplant density, conditions are favoured. They use provided a year or two after colony boundaries tend to be well areas where there is bushy growth clearance, once ground vegetation defined. Populations in small or of the foodplants, generally less than has started to develop but before sub-optimal habitats with only minor 10cm tall, although very short areas the coppice regrowth becomes barriers to dispersal tend to have a are not used for breeding. They prefer established. On thin soils, or where more open structure and exchange a mixed vegetation structure with deer browsing delays initial regrowth, individuals more frequently with other bare ground patches for basking and these conditions can be prolonged nearby patches. Populations are tall plants nearby, which are used for for several seasons. typically small (10 to 100 adults seen roosting. at peak) but some can contain as Scrub habitat: Patches of scattered many as 1,000 adults. Habitat management young scrub (less than 5 to 10 years Aim to maintain a continuous old) should be retained, ideally with a Foodplants supply of open habitat that contains proportion cut each year on rotation. A variety of plants from the Rosaceae foodplants growing over bare ground As in coppice, the butterfly will use family are used, mainly Agrimony, in sunny conditions with varied the regrowth a year or two after Creeping Cinquefoil and especially vegetation nearby. Conditions can be clearance and will disappear once Wild Strawberry. The butterfly provided by clearing woodland plots, scrub shades the site. may also use Barren Strawberry, coppicing and by ride management. Tormentil, Salad Burnet, Bramble, Ride management: Occasional Dog-rose, and Wood Avens. surface disturbance along wide Dan Hoare sunny rides is beneficial in creating bare ground and areas where the foodplants can germinate. This can be achieved by cutting low to the ground, through scarification of the surface or through general disturbance by machinery. Coppicing ride edge vegetation on a short rotation may also be helpful where no substantial area can be managed as coppice. A network of open, sunny rides and glades is essential to link Ride edges provide ideal habitat with clearings within high forest woodland. strawberry, cinquefoil and Bramble spreading over bare ground

Woodland management for butterflies and moths | 45 Wood White Jim Asher

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management High forest and coppicing: Suitable conditions can be provided by Wood Whites form discrete Aim to maintain a continuity of open, ensuring a sequence of felling and colonies at most sites, but these sunny areas with and without scrub, replanting to create an uneven- vary considerably in their size lightly shaded by surrounding trees. aged forest, combined with the and density. In some cases, high Maintain abundant vetches growing maintenance of a network of sunny densities occur in very discrete areas, in a variety of conditions, from low rides and glades. Reintroduction but where the breeding habitat is vetch growth in sparse vegetation to of coppicing can also improve more scattered, adults occur at low tall straggling vetch growth through woodland structure and provide densities over wide areas. There may fairly dense vegetation. suitable habitat. A wide ride network be considerable movement around is also needed in coppiced woodland. the wider countryside if a suitable Ride and glade management: network of appropriate habitat is Provide suitable breeding habitat by available. widening overgrown, shaded rides and keeping glades open. Ensure

Foodplants that the tall vegetation Dan Hoare zone of the verges is cut on a 3 to A variety of legumes are used, 6 year rotation - shorter rotations the most common being Meadow are not suitable. Damp conditions Vetchling, Greater Bird’s-foot-trefoil, along boundary banks and ditch Common Bird’s-foot-trefoil and edges are especially favoured and Bitter-vetch. Wood Whites often have should be maintained as sheltered two generations each year, and may but unshaded habitat. The inclusion breed on different foodplants at the of scalloped bays and box junctions same site in spring and summer will also be beneficial and increase broods. connectivity between existing breeding habitats. It can be beneficial Woodland habitats to create patches of short vegetation Wood Whites can occupy a range with bare ground by scarifying ride Breeding habitat for Wood Whites in of habitats but particularly strong spring: short vegetation with Common edges and ditch banks, or by cutting Bird’s-foot-trefoil populations are found in woodland the ride-side scrub zone on a long landscapes with extensive open rotation. space and scrub. They breed in grassy vegetation in open woodland rides, sunny glades and the sheltered edges of scrub.

46 | Woodland management for butterflies and moths Brown Hairstreak Peter Eeles

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat Management Blackthorn in hedgerows and wood edges: As eggs and caterpillars Colonies are normally centred on a The overall aim is to maintain occur on Blackthorn twigs for much wood, but egg laying usually extends a continuous supply of young of the year, any hedge or wood over several square kilometres of Blackthorn stands along the edge trimming can remove a large the surrounding countryside. Adults woodland edge, in rides and in proportion of the population, and tend to congregate around specific hedgerow thickets. annual cutting is particularly harmful. groups of trees, particularly in mid Appropriate cutting regimes are August when they are seeking mates. Retention and planting of essential if this species is to survive at The same trees, usually prominent Blackthorn: Maintain all farm woods a site and these can be considerably Ashes, are used for this purpose from and broadleaved wood edges and cheaper than annual cutting: year to year. Where these trees can retain any trees identified as key mating sites and congregation be identified they should be retained • Trim hedges only once every 3 to 5 points. When creating new woods, whenever woodland management years and do not cut all the hedges rides or glades, consider planting occurs. in any one area in the same year. Blackthorn along sunny, sheltered As an absolute minimum, hedges edges. Use opportunities to restore or Foodplants should be left uncut every other create hedgerows using Blackthorn, Blackthorn is used exclusively by year. especially where they can link either most colonies, but occasionally existing hedges and/or woodlands. • Cut as late as possible in the winter, Wild Plum and other species ideally in January or February, are used. Eggs are usually laid and Blackthorn in coppice: Coppice which will also make shelter and overwinter on young Blackthorn or fell trees on rotation (7 years or hedgerow fruit available to other growth in sunny, sheltered positions, longer). Spread any clearing or wildlife such as small mammals and so are very susceptible to winter coppicing work over several years birds hedge cutting and extensive scrub and leave some belts of woodland • Hedge laying on a rotation of over management. intact to act as focal points for the 7 years is highly suitable. It colony. produces the young growth that Woodland habitats provides good egg laying sites and Blackthorn scrub in glades and A complex of woodland, scrub and avoids the annual cutting that can rides: Cut on rotations of more than hedgerows with abundant, suitably remove both caterpillars and eggs 3 years and do not cut entire ride managed, Blackthorn is required. • Avoid chemical spraying into hedge Most colonies occur on clay or heavy sections or glades in a single year. Creating new east-west rides within and wood edge habitat, leaving an soils where Blackthorn is a dominant uncultivated margin if possible constituent of the hedgerows or woods can be valuable, especially scrub. where they link existing egg-laying • Heavy browsing of Blackthorn by areas. livestock such as ponies can have a negative impact on the butterfly, as can rabbit and deer browsing on young shoots

Woodland management for butterflies and moths | 47 White-letter Hairstreak Martin Warren

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Woodland habitats Hedgerow management: Avoid trimming elm hedgerows until after Information on colony structure is The White-letter Hairstreak will July, ensuring that larvae have a sparse, but a marking experiment breed wherever elms occur and plentiful supply of flowers and young along one ride revealed a population so is not exclusively a woodland leaves to feed on. Wide field margins of several hundred butterflies with species. It can occur along sheltered should be retained for nectar sources individuals regularly moving up to hedgerows, within mixed scrub, wood such as thistles and brambles. 300m between trees. Many colonies edges and the edges of woodland are restricted to a small group of trees rides. It will also use large isolated Planting: Where possible include and most appear fairly sedentary, elms, irrespective of the surrounding elm of local provenance in new although wider dispersal can occur habitat. woodlands and hedgerows. Disease- and individuals have been seen resistant hybrid trees can now be several kilometres from known Habitat management obtained, and research continues to breeding sites. The overall aim is to maintain elm examine their suitability for White- trees in suitable conditions, which will letter Hairstreaks. Foodplants provide habitat for a wide range of The butterfly breeds on various elm invertebrates including many moths. species, including Wych Elm, English Elm and Small-leaved Elm. It will Retention of elm trees: Woodland also use elm hybrids. A preference and hedgerow management that and higher breeding success on retains elm trees will benefit the Wych Elm has been demonstrated White-letter Hairstreak. Fell and Elizabeth Goodyear at one site and this species may be debark trees infected with Dutch Elm used almost exclusively in northern Disease, as weak and dying elms . The butterfly prefers to provide the habitat for broods of elm breed on flowering trees, but smaller bark beetle which will spread further elms, including suckers, may be infection. used. Suckering, regrowth and coppicing: Encourage suckering of elm from roots or regrowth from cut stumps. Elm regrowth usually becomes White-letter Hairstreaks breed on elm infected with Dutch Elm Disease at growing in a wide variety of situations about 12 years, when it reaches 5 to 10m tall, so coppicing elm on a 10 year cycle will limit re-infection.

48 | Woodland management for butterflies and moths Black Hairstreak Peter Eeles

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management Laying Blackthorn like a hedge may also be effective, especially when The Black Hairstreak is a very The overall aim is to maintain dense the cut material is laid with a south- sedentary butterfly that often breeds mature 3 to 4m high Blackthorn facing aspect maximising the sunlight in the same small, discrete part of a stands along wood edges and rides received by the regrowth. However if wood or thick hedgerow for 20 years and in hedgerow thickets. the Blackthorn is old, laying may be or more. Larger woods may contain impractical without snapping stems. several separate breeding areas but Retention of Blackthorn: Any major Compared to cutting, laying also has butterflies are rarely seen outside clearance of Blackthorn in woods the advantage of potentially reducing woods, except along thick hedgerows and hedges within the range of this the impact of management on over- with abundant mature Blackthorn. butterfly should be avoided. wintering eggs. The Black Hairstreak has very limited Blackthorn management: Cut even- powers of dispersal. One introduced aged Blackthorn stands in small, Planting: Include Blackthorn stands colony in Surrey spread 1.5km over 10 to 15 square metre patches (or in any new woodland plantings within more or less suitable habitat in 30 10 to 15m lengths of hedgerow), on the Black Hairstreak’s range. Select years and even slower dispersal rates long rotations. Rotations of 20 to 50 south-facing, sheltered locations, are recorded in its traditional East years may be appropriate depending unshaded by trees. Only plant half the Midlands woodlands. upon the site, allowing mature stands available area and create indented to develop. No more than 25% of edges. Foodplants habitat should be cut at any one Deer management: In some woods, Blackthorn is used exclusively by time, substantially less on small natural regeneration of Blackthorn most colonies, but occasionally Wild sites. Cutting irregular indentations is limited by high density deer Plum and other Prunus species are into the Blackthorn will provide more populations, particularly introduced used. sheltered conditions. Create new Muntjac and Fallow deer. Cutting habitat nearby by allowing Blackthorn Blackthorn at 1.5 to 2m height or Woodland habitats to spread through suckering. On laying Blackthorn like a hedge can woodland sites, remove trees which Most colonies breed in dense mature reduce grazing of regenerating directly shade Blackthorn thickets, stands of Blackthorn growing in shoots. Fencing Blackthorn but retain tall hedges where they sunny, but well-sheltered situations, regeneration plots has also been provide shelter. usually along wood edges, the edges used to protect against deer damage, of rides or glades, or in hedgerow but reducing deer populations to thickets. Smaller colonies will occur acceptable limits is likely to be a more in exposed or shady situations, such effective long-term strategy. as canopy gaps in mature woodland, small patches of scrub or in sheltered hedgerows.

Woodland management for butterflies and moths | 49 Duke of Burgundy Sam Ellis

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Woodland habitats Coppicing: In coppice it tends to use coupes with 2 to 5 years of The Duke of Burgundy can survive This species occurs in two types regrowth. A regular cutting sequence in very small colonies within limited of habitat: woodlands and poorly- of woodland blocks in close proximity pockets of suitable habitat, although grazed, rough limestone . will ensure rapid colonisation of new it is capable of forming large In woodlands, clearings on ancient habitat, particularly where open rides populations on the rare occasions woodland sites, regenerating permit movement between clearings. when suitable habitat conditions coppice, young plantations, sizeable Ideal conditions are provided in occur across an extensive area. glades or wide rides are used. The woodland regrowth a few years Males are territorial and rarely butterfly requires foodplants growing after clearance, when sheltered move far from favoured positions in among tussocky vegetation, often areas develop between coppice sheltered hollows or gaps between near to light scrub. North or west- stools. On thin soils or where deer bushes that catch the early morning facing slopes are preferred, possibly browsing delays initial regrowth these sun. In contrast, females are far less because the humid conditions microhabitats can be prolonged for conspicuous but appear to be more encourage lush growth of the several seasons. mobile and move more freely through foodplant and prevent it from drying it the habitat. In a mark-recapture during the summer. Rides: Breeding success is likely study, over half of recaptured females to be highest in east-west rides. had moved more than 250m. Some Habitat management Suitable habitat along open rides females may disperse several Aim to ensure a continuous supply of can be maintained by cutting back kilometres and sites have been clearings with abundant Primulas in the woodland edge to 5-8m and by colonised up to 5km from known sunny but sheltered conditions. cutting bays into the scrub zone on populations. rotation every 5-8 years, depending Glades: Permanent glades can be on the vigour of regrowth. The aim is Foodplants maintained by controlling scrub to create sheltered areas with fresh The main foodplants are Primrose regrowth, brambles and coarse growth of Primulas. and Cowslip although ‘False Oxlip’, grasses, ensuring all cut material the hybrid of these two species, is is removed. As well as hand tools, sometimes used. On sites with both strimmers, clearing saws, or a

species, Cowslips are the preferred mower set at 10cm can also be very Dan Hoare foodplant. Crucially, foodplants effective. Annual cutting will usually need to be in a lush, upright growth leave a site too short or exposed, and form, usually found in semi-shade or management every 2 to 3 years may long vegetation. Exposed plants, or be more suitable. At several sites the those with prostrate leaves low to the butterfly breeds in young plantations ground, are not suitable for breeding, where the crop has failed; in such and even if eggs are laid on them the conditions gradually removing small plants will usually wither before the trees over several years can maintain caterpillars are fully developed. the habitat better than suddenly Lush Primrose plants growing among clearing the site. tall grasses, or at the edges of scrub, provide ideal egg-laying sites for Duke of Burgundy

50 | Woodland management for butterflies and moths White Admiral Jim Asher

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management Ride and glade management: The generic managements detailed White Admirals form discrete colonies Aim to produce semi-shaded in Section 3 will provide good and typically occur at low densities. conditions in woodlands to support conditions for this species. Scallops The mobility of adults has not been the breeding habitat of spindly, and box junctions can also be studied in detail, but the spread of trailing growths of Honeysuckle within created to provide more open habitat. the butterfly during the 20th century a few metres of flower-rich, open, Encourage and retain patches of indicates that it can colonise over sunny rides and glades. Adults will flowering Bramble in sunny, sheltered distances of many kilometres. require nectar sources along ride locations. Between the 1920s and 1930s, the edges and in sunny glades, and will distribution extended by distances especially use flowering Bramble Deer management: Extensive up to 100km, implying an average patches. Note that exposed, lush browsing of Honeysuckle has been spread of up to 10km per year. High Honeysuckle plants are not used for highlighted as a problem at some mobility is also indicated by sightings breeding, which occurs inside the sites, so deer control may be needed. some kilometres from known shaded crop edge. colonies. Deciduous high forest and Foodplants coppicing: Retain mature woodland or over-mature coppice blocks The sole foodplant is Honeysuckle, Neill Bruce although dense over-mature with the butterfly using trailing woodlands which contain few sunny tangles of the plant in dappled shade. rides and glades are unsuitable. Honeysuckle growth along the ground is not used. Conifer plantations: Retain abundant Honeysuckle along semi-shaded Woodland habitats ride margins. Such habitat can be The butterfly is only found in enhanced by encouraging a belt woodland habitats. It occurs in of broadleaved trees along the ride deciduous, mixed deciduous/ edges. Thinning conifer plantations coniferous and coniferous woodland, can often create suitable dappled often in neglected condition or at shade and Honeysuckle growth. a mature growth stage. The young Honeysuckle trailing from trees or shrubs stages of coppice or woodland in partial shade provides ideal breeding regrowth are not used. Both thicket habitat stage and mature conifers can support suitable Honeysuckle growth, but this can be absent from some broadleaved woodlands, notably Ash and Beech.

Woodland management for butterflies and moths | 51 Purple Emperor Neil Hulme

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure thicket stage conifer plantations and Sallow management: Purple broad-leaved woodland, as well Emperors will not use isolated bushes There is little detailed information as the scrubby edges of adjacent in sunny situations on the ride edge, on the structure of Purple Emperor habitats such as heathland. although retaining such sallows populations, partly because the during ride widening can be valuable elusive adults are difficult to study. for other insects. This is a canopy-dwelling species Habitat management The Purple Emperor requires large that almost invariably occurs at low Sallows growing in ride-side ditches blocks of broad-leaved or mixed population density, and the adults are are often trimmed to prevent them woodland, clusters of smaller woods inactive for long periods. Populations leaning over forestry tracks. Minimise and/or dense scrub where sallows probably consist of adults breeding at damage by clearing ride edges on are abundant. Age diversity within low density in favoured spots across rotation, and developing a wider ride a woodland complex or a group of large, well-wooded landscapes. edge containing sallows of different woods is essential for this butterfly In some situations the males ages. Trees leaning over the ride can to survive and thrive over the long- congregate around prominent trees also be pushed back into the wood or term. The best sites are those which or groups of trees, often at, or just laid sideways along the ride. Although combine mature woodland and downwind of, a highpoint in the pollarded sallows are sometimes younger growth. landscape. Mated females may be used by Purple Emperors, it may take highly mobile and have been seen many years for the vigorous regrowth dispersing along mature hedgerows Focus on the provision of abundant sallows in a range of situations to become suitable. Where damage is as well as across open fields between unavoidable, encourage growth away nearby patches of woodland. across the landscape. Sallows are comparatively short-lived trees, so from the ride by creating bare muddy scrapes or planting cuttings several Foodplants it is important to ensure a continuity of trees of various ages. Purple metres behind the ride bank. Goat Willow is the most widely used Emperors prefer trees growing Planting: Include sallows in any foodplant although it also breeds on in semi-shade and in sheltered woodland plantings. Sallows will other sallows and . Eggs are conditions, often with northerly or regenerate freely in damp bare soil, laid mainly beneath the canopy of easterly aspects. Sallow foliage but they also be easily propagated by tall broad-leaved sallows, or in other exposed to full sun is not used. Egg- pushing 2cm thick, 1m long cuttings situations where the foliage is shaded laying occurs in a variety of woodland into the ground during the autumn. from late summer sun. Sallow growth situations including ride edges, in quite heavy shade, and often on scallops, woodland edges, riversides, Deer management: Sallow regrowth larger trees, is preferred. canopy gaps and road verges. Retain is highly palatable to deer. Tree- sallows where possible and avoid guards may be necessary to protect Woodland habitats major sallow clearance in woods new cuttings, but managing deer This is predominantly a woodland and hedges in the area of a colony. numbers to reduce damage is the species which will occur in and Note that sallows also provide a key best long-term solution. around both ancient woodland and nectar source and important breeding secondary woodland if suitable habitat for a wide variety of insects sallows are abundant. Breeding including many moths. sites can include ride edges, glades,

52 | Woodland management for butterflies and moths Small Pearl-bordered Fritillary Gareth Knass

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management habitat. Colony structure and mobility Aim to provide flower-rich open Bracken dominated clearings: appears to vary with landscape. clearings and rides, especially Aim to maintain abundant violets in Studies of colonies in mosaics where the habitat is damp with lush medium height swards in association of damp grassland and Bracken vegetation. This butterfly breeds with Bracken. Suitable conditions are suggest that adults are highly in open areas a few years after most easily identified in spring when sedentary, remaining within the same clearance, as the ground vegetation violets are more conspicuous before small habitat patches. However, a begins to develop. the Bracken canopy closes. Grazing study in an extensive conifer forest is a good management option (cattle Glades, clearings and coppice: Use in Wales showed much greater adult or ponies are best), but if this is the management options outlined in mobility with occasional movements not possible, then some other form Section 3. Continuity of management between 1 and 3.5km. The species of Bracken management is often is essential and clearings should be may also range widely in more needed to maintain the violets and connected by broad sunny rides. extensive and open habitats such as the required grass/Bracken mosaic Traditional coppice management those in Scotland and western and (see Section 3). northern Britain. can produce ideal conditions for the butterfly. Within glades, scrub Wayleaves: The regular cutting of Foodplants clearance on rotation can be regrowth on wayleaves provides undertaken, but not all scrub should The most widely used foodplants suitable sheltered sunny habitat, and be eliminated as it often provides are Common Dog-violet and Marsh their linear nature means that they shelter. Violet, although other violets may can act as ideal corridors along which individuals can fly to neighbouring occasionally be used. Rides: The species can breed along colonies. ride edges if they are wide enough Woodland habitats (at least 5m). Using a three zone ride Wood-pasture: Light cattle and pony This species can be found in a system and cutting the scrub zone grazing can be a useful management wide range of open habitats. Within on a rotation of 8 to 20 years can tool, helping to keep the habitat open woodlands the butterfly uses mainly supply this habitat. Where the taller whilst also promoting floral diversity. sheltered, damp grassy habitats vegetation zone has a high Bracken Trampling by stock can provide including glades and clearings, component, breeding habitat can suitable ground conditions for the Bracken and patches of scrub. In be produced by cutting sections establishment of violets. However, Scotland it can be found in open on a 3 to 5 year rotation (adjust the heavy grazing will remove nectar wood-pasture and wood edges, rotation according to the growth rate sources and damage breeding usually where there is some grazing of Bracken, violets and the build-up habitat, particularly during spring. by deer and/or sheep. of litter). Damp conditions along If foodplants are threatened by the boundary banks and ditch edges development of tall or dense ground are especially favoured and should vegetation this should be controlled, be maintained as unshaded habitat. initially by heavy grazing and then The inclusion of scalloped bays at maintained with lighter, intermittent intervals along the south-facing edge grazing. can provide additional sheltered

Woodland management for butterflies and moths | 53 Pearl-bordered Fritillary Gareth Knass

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure In woodland the butterfly uses rides Glades, clearings and coppice: and clearings such as recently Best produced by coppicing or group Usually forms discrete colonies coppiced or clear-felled woodland, felling of high forest, but continuity around suitable breeding areas, often and wayleaves and open woodland of management is essential and comprising many hundreds of adults, in Scotland, where most sites have clearings should be connected by although most habitats are transient. a sunny, south-facing aspect. In broad sunny rides. Note that many Adults move freely within their all habitats it requires abundant clearings are unsuitable, including colonies and regularly cover 100m foodplants growing in short, sparse those on damp ground, or those or more. When population densities vegetation with plentiful leaf litter or dominated by plants such as Dog’s are high a significant proportion of dead Bracken fronds. Bracken is an Mercury, Bluebell or vigorous butterflies will disperse, particularly important feature in most woodland grasses. during sustained hot weather. colonies. Bugle is an important Marking experiments have shown nectar source, and adults are often Ideally, coppice adjacent woodland that individuals can move at least seen nectaring along rides, but it plots of 0.5 to 2ha in succession 4.5km between adjacent colonies. is the violet-rich, warm leaf-litter and retain standard trees (especially Nearby colonies are thus often linked habitat used by the caterpillars that oaks) at less than 20% canopy cover. and the butterfly almost certainly appears to be the key factor limiting Standards provide essential leaf forms metapopulations covering population growth at most sites. litter, although the leaves of some networks of discrete breeding areas. species such as Ash and Beech are Conversely, in poor weather adults Habitat management less suitable, and standard density are highly sedentary and may fail to should never be so high that it casts Aim to produce a succession of colonise suitable new habitat nearby. excessive shade. In high forest, flower-rich, sunny clearings with suitable conditions can be provided violets growing amongst sparse Foodplants by a regular sequence of felling and vegetation where there is abundant Common Dog-violet is used most replanting with deciduous trees. brown leaf litter or dead Bracken. widely. Other violets such as Heath Maintain open space to allow adults Dog-violet and in the north, Marsh to disperse to adjacent colonies and Violet and Hairy Violet can be used. newly cleared habitat. Providing an interconnected network of open Woodland habitats habitat is crucial, as even a 100m This species was closely associated wide stand of 10 year old coppice with coppice in the past, but has has been shown to act as a barrier to been lost from many woods where females. management is too infrequent to support it. Colonies are also found in other habitats such as Bracken- dominated rough grasslands, and in Scotland these habitats are often side by side.

54 | Woodland management for butterflies and moths Dan Hoare Dan Hoare

Egg-laying site for Pearl-bordered Fritillary Conifer removal on the northern edge of this track has created breeding habitat in among sparse debris in recently cleared a sheltered, sunny ride edge with scattered bracken coppice

Bracken-dominated rides and Rides: The species can breed in ride Wayleaves: The regular cutting of clearings: Grazing is an excellent edges if verges are at least 5m wide, regrowth on wayleaves provides management option for this but colonies rarely survive in rides suitable sheltered and open habitat, butterfly (cattle or ponies are best). alone, and usually require additional and their linear nature means that As an alternative, other forms of scallops, coppicing or clearfells to they can provide good connections management will be needed to keep maintain populations in the long-term. between colonies, particularly in Bracken at the right level: too much Rides should be managed to produce dense plantation woodlands. Regular and the foodplants are shaded out; a continuous supply of violets management to maintain a mosaic of too little and there is insufficient litter growing amongst sparse vegetation Bracken and flower-rich grassland, or for basking caterpillars. The Bracken with abundant leaf litter. Using a three rotational cutting which approximates management detailed in Section 3 zone ride regime and cutting the to a short coppice regime can both can be used to produce and maintain scrub zone on a rotation of 8 to 20 produce breeding habitat for this the required sheltered microhabitat: years can supply this habitat. Where species. violets in short, sparse vegetation the tall grassland zone of the verge with patches of light Bracken litter, has a large Bracken component then Grazing: The ideal management of often where last year’s fronds have breeding habitat can be produced non-coppice sites for Pearl-bordered collapsed. Where the litter forms by cutting sections on a 3 to 5 year Fritillary is often light cattle and pony a thick even layer it will no longer rotation. grazing. This helps keep glades open be suitable, and raking or grazing whilst also keeping areas flower-rich. will be needed to encourage violet Boundary banks and ditch edges Trampling by stock can help prevent germination. Suitable conditions are are often favoured as they provide scrub from becoming too dominant, most easily identified in spring when the warm, well-drained conditions as well as providing suitable ground violets are most conspicuous before needed for larval development. conditions for the establishment of the Bracken canopy closes. Rides running east to west are ideal violets. However, heavy grazing will as they have a greater proportion of remove nectar sources and damage warmer south-facing edges. Including breeding habitat. scalloped bays at intervals along the south-facing edge provides additional sheltered habitat.

Deer management: The effects of deer on Pearl-bordered Fritillary habitat are complex and can vary considerably between sites. Fencing coppice coupes or controlling deer numbers may be necessary where browsing is damaging regeneration. However at some sites high deer populations can prolong habitat patch occupancy by slowing the rate of regrowth.

Woodland management for butterflies and moths | 55 High Brown Fritillary Neil Hulme

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management Bracken and grass mosaics, including woodland clearings: Aim The butterfly forms discrete colonies In woodland, ride verges do not to maintain mosaics of moderate/ that rarely contain more than a few seem to produce adequate habitat dense Bracken interspersed with hundred adults. However, the adults for this species although coppice grassy patches and canopy gaps. are highly mobile and are often seen coupes, patchy scrub, and Bracken- The species requires abundant feeding on flowers 1 to 2km away dominated clearings do support violets growing through variable, from main breeding areas. They seem colonies. but fairly deep levels of Bracken to travel freely between such areas litter (usually at least 1.5 cm deep). and the flight area of many colonies Coppice and woodland/scrub See Section 3 for more on Bracken is over 50-100ha. In favourable years clearings on limestone rock: Aim to management. Importantly, there the butterfly may establish temporary maintain a regular supply of clearings should be only limited grass cover colonies in smaller or marginally with abundant violets. Ideally, cut or other vegetation. Grazing is the suitable habitats, although potential coppice on adjacent plots of 0.5 most effective option, but cutting, breeding areas can come in and out to 2ha in size in succession with spraying or burning can also be of suitability, possibly as a result of open, sunny rides interlinking plots. used. Suitable conditions are most variability in grass growth. Similarly, patchy scrub clearance can also provide regular openings in easily identified in spring when violets Foodplants which suitable ground vegetation may are conspicuous before the Bracken develop, particularly on rock outcrops canopy closes. Common Dog-violet is used in all or very thin soils. Breeding may also habitats, but Hairy Violet is also occur in adjacent limestone grassland used in limestone areas. It may where soils are naturally very thin

occasionally use Heath Dog-violet Sam Ellis and where violets are abundant. Light and Pale Dog-violet. grazing may also help maintain these habitats although precise stocking Woodland habitats regimes are not well understood. In the past this was considered to be a woodland species associated with coppice, but most of its few remaining colonies are now outside of woodland or in atypical woodland habitats. Within woodlands the butterfly uses Bracken-dominated clearings or grass and Bracken mosaics on south facing slopes or level ground below 300m. Limestone Ideal breeding habitat for High Brown Fritillary on recently coppiced limestone rock outcrops where woodland or rock outcrops, Cumbria. scrub has recently been cleared or coppiced are used in the Morecambe Bay Limestones of south Cumbria and north Lancashire.

56 | Woodland management for butterflies and moths Silver-washed Fritillary Peter Eeles

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management Glade management: Applying the management approaches described Silver-washed Fritillary adults Aim to maintain open canopy in Section 3 is likely to provide ideal are highly mobile and fly rapidly deciduous woodland with flower- Silver-washed Fritillary breeding between clearings, including over the rich, sunny rides and glades. The habitat. woodland canopy. In most regions butterfly is the most shade tolerant of the butterfly forms discrete but loose the violet feeding fritillaries and does colonies within individual woods. not require the large open spaces However, individuals have been seen needed by the other species.

considerable distances from known Dan Hoare breeding areas in several regions, High forest and coppicing: especially in south-west England Occasional thinning of deciduous where they are regularly seen flying high forest woodland, combined with along wooded lanes. the maintenance of sunny rides and glades provides suitable conditions. Foodplants Opening up the canopy too much will promote excessive coarse grass and The main foodplant is Common Bramble growth to the detriment of Dog-violet growing in shaded or the violets, although winter bramble semi-shaded positions on the cutting and raking can maintain woodland floor, amongst pockets of suitable conditions for at least a few leaf litter and other sparse vegetation. years. Traditional coppicing also Eggs tend to be laid in fairly shaded provides some suitable breeding Oak standards amid an open sunny locations, on tree trunks near patches habitat at the shady edges of recently understorey provide ideal breeding habitat of violets. cut areas, within older coppice for Silver-washed Fritillary or around standard trees. The Woodland habitats species can tolerate higher standard The main habitat for this species is densities, and more shade, than the woodland, although in parts of south- other violet-feeding fritillaries. west England and Ireland, wooded hedgerows and sheltered lanes near Ride management: A three zone to woods are also used for breeding. ride regime supplemented with The butterfly occurs primarily in rotational cutting of clearings is ideal. broadleaved woodland, especially Scallops and box junctions can also oak woodland. However, some types be created to provide more open of broadleaved woodland, notably edge habitat. Management should Ash and Beech do not seem to be be planned in sections to avoid favoured. Other habitats used include disrupting large areas at any one mixed broadleaved and conifer time. Leaving scattered brash on plantations, especially where these scallop edges may discourage deer have been thinned to promote a from excessive browsing of breeding broadleaved understorey. areas.

Woodland management for butterflies and moths | 57 Heath Fritillary Caroline Bulman

J F M A M J J A S O N D Egg Caterpillar Chrysalis Adult

Population structure Habitat management Deer management: Where deer are abundant it will normally be This species is highly sedentary and Aim to ensure a succession of sunny necessary to fence newly coppiced forms compact colonies centred on clearings with abundant Common areas, to allow good regrowth of both its favoured breeding areas. Adults Cow-wheat, in otherwise sparse the coppice stools and the foodplant. rarely move more than 100m but a vegetation. Coppicing or group In the long-term, managing deer few individuals have been known to felling of high forest woodland populations to reduce their impact disperse up to 2km. Despite the fact best produces such clearings, but may be a better option. that its habitats are often short-lived, continuity of management is essential it has a very limited colonising ability as is the close proximity of new and suitable habitats more than 600m habitat to existing colonies. from a population are colonised only slowly, if at all. Effective conservation Ride management: Wide sunny rides Dan Hoare therefore needs to include careful are needed for the species to move planning of successive clearings in a to new, freshly cleared areas where very local network. conditions are suitable for breeding. Open rides can be maintained by Foodplants cutting back the woodland edge to 5 to 8m and cutting the scrub-zone The main foodplant on woodland on short-rotation (cut 5 to 8 years), sites is Common Cow-wheat, depending on the vigour of regrowth. although Ribwort Plantain and In the Blean Woods, small colonies Foxglove can be secondary can occur in ride edges where foodplants. Other foodplants are used Common Cow-wheat occurs, and Common Cow-wheat growing in sunny on a few heathland habitats in south- situations provides ideal breeding habitat, occasional colonies have been found west England. while shaded plants may not be used on Ribwort Plantain where the main foodplant is absent. Ride habitat on Woodland habitats its own appears insufficient to support The Blean Woods of Kent are the populations in the long-term, which stronghold of the Heath Fritillary. The require the occasional larger areas of Dan Hoare butterfly has also been re-established high quality breeding habitat provided at four woodland sites in Essex and by woodland clearings. one site in Devon since the 1980s. It also occurs outside woodlands Coppice: Coppice coupes (0.4 to in sheltered heathland combes on 2ha) on a rotation of 10 to 20 years, Exmoor. In woodland, the favoured preferably cutting adjacent plots habitat is recently cut Sweet Chestnut within three years, or within 300m or Hornbeam coppice where of an existing colony. Coupes can Common Cow-wheat is abundant, as be colonised in the first year after well as newly felled woodland on acid felling, but will rarely remain suitable for more than four years before the Coppice coupes do not remain suitable soils. for long, so a regular cycle of clearance is regrowth becomes too dense. needed

58 | Woodland management for butterflies and moths