Managing woodland for butterflies and moths
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Managing woodland for
butterflies and moths
Why manage woodland at all? Surely a natural woodland, without
(or with minimum) intervention would best supply sustainable
habitat for butterflies and moths?
The answer lies in the processes cleared woodland habitats. The For many species, the speed and
that have formed our present natural processes that produce such extent of this change has made it
landscape. Almost no woodland habitats within woodland (such as very difficult to adapt and landscape
in Britain today can be considered fires, storms and the natural collapse changes have reduced opportunities
wholly natural. We have inherited a of aging trees) typically occur too to relocate to suitable habitat
long history of forestry use that has infrequently to provide the continuous elsewhere.
substantially modified even our most cycle of clearings needed by these
ancient woodlands. We have, and species. Woodlands would also have Overall objectives
still are, continuously changing the been subject to regular, extensive This guide outlines specific woodland
composition and structure of woods grazing and browsing by large management options designed to
to meet our needs. The woodland herbivores which are now absent, benefit butterflies and moths. These
wildlife we see today is a product of and these effects are not replicated options are designed to achieve the
that history and many Lepidoptera by the increasing number of deer following overall objectives:
survive in woodland habitats only now browsing our woods. The small
because of repeated human use of size and fragmentation of most • Structural complexity
woodland resources. woods in the UK also prevent natural • Habitat diversity
processes operating at a sufficient
scale to conserve the full range of • Foodplant diversity
David Green
woodland wildlife. Low-intervention • Management continuity
management strategies can make • Landscape connectivity
a contribution to the mosaic of
habitats within a landscape, but need The single most important factor
to be complementary to an active that makes a woodland good for
management process that maintains butterflies and moths is a diverse,
and enhances the valuable habitat uneven structure. This should
features found in our woods. include some mature or tall trees,
Our current suite of woodland some dense regrowth, numerous
species coexisted in the past sunny rides and glades (both large
alongside often extensive active and small) and patches of recently
management of woodlands. So cleared and regenerating open areas
why is woodland management now with sparse ground vegetation and
considered a conservation issue? The warm unshaded conditions. This
Sustainable removal of timber and reason lies in the extreme speed and diverse woodland structure creates a
firewood is an important part of woodland the huge scale of recent changes. variety of habitats necessary for the
management The usage of woodland has always various life stages of Lepidoptera,
changed over time, but change has including larval foodplants growing
In Britain, applying a non- happened very rapidly in the last in appropriate conditions, a limiting
intervention approach using only hundred years. This has occurred not factor for many species.
natural processes within most of just within one type of woodland or Such a varied structure, with a diverse
our woodlands will not create the one region of Britain, but across the range of tree and plant species,
habitats needed by many of our whole landscape. At the same time not only provides good habitats for
butterflies and moths. For example, urbanisation and intensive agriculture Lepidoptera, but also for a wealth
many of our rarest butterflies are has removed or highly fragmented of other insects and forest wildlife.
highly dependent on open, newly much of our woodland network.
14 | Woodland management for butterflies and moths
Specific requirements for specialist Managing across patch is likely to undergo regular
species requiring deadwood, lichens, local extinctions and regular re-
mosses or wetland features can be
the landscape colonisations. Problems arise when
integrated with this overall aim. Looking beyond the survival of the breeding patches become
species on single sites, conservation isolated, either by distance and/or
Continuity of management is the must operate at the landscape scale because the intervening landscape is
next vital factor to consider. Species to be effective in the long-term. There hostile.
usually occur on a site because its is now considerable evidence that
past use has created the habitat they the populations of many if not most Managing habitats at the landscape
need, and periodically repeating that butterflies and moths function as scale is essential given the evidence
management will be necessary for metapopulations. This is defined as a that some species are already
them to persist. This is particularly collection of local populations which shifting their geographical range,
important at sites with a long history occupy discrete habitat patches but their habitat use and the timing of
of a specific management regime. which are connected by occasional their life cycles in response to climate
Where woodland landscapes have dispersal of individuals. Each habitat change. Enabling species to move
become fragmented management
continuity is essential as it is harder
for species to move to alternative
habitats elsewhere. What butterflies and moths need
Continuity of management is also Indeed, adult butterflies may
important because habitats are be encountered in parts of the
dynamic: they will constantly change, woodland away from the vital
often over very short time periods. breeding habitat, especially when
Fundamentally, most woodland searching for nectar. In general,
management for Lepidoptera is Lepidoptera require sheltered,
about working within a cycle of warm sunny places as adults, often
habitat succession rather than trying with a nectar source, as well as
to maintain areas in a fixed state a suitable place to lay their eggs.
over time. In particular, trying to hold The larvae will then require plentiful
a permanent open area at an early foodplants, often growing in specific
stage of woodland succession (such conditions, and will move to a
as that used by Heath Fritillary) is sheltered or inconspicuous spot
almost impossible. Regular cutting to pupate before emerging as an
or grazing may keep the site open, Peter Eeles adult. For highly threatened species
but will usually cause the woodland A Purple Emperor emerging from its in particular, understanding where
ground flora to be replaced by a chrysalis on the underside of a sallow leaf they spend each of these stages,
grassland community which may and at what time of year, can be the
not support the target species. Understanding the life cycles of key to effective conservation. Land
Most sites will require a shifting and butterflies and moths provides managers sometimes concentrate
diverse habitat mosaic, created and an insight into what they need on providing the nectar-rich areas
maintained by regular management from woodland habitats. All frequented by adult butterflies
on different parts of the site to butterflies and moths go through (where they are most often seen)
produce younger growth stages a complex lifecycle from egg to at the expense of other habitat
(clearings or short, herb-rich swards) larva (caterpillar) and then pupa features. In fact it is rare that nectar
which will in turn provide other (chrysalis) and adult. Some species is the factor limiting population
habitats as they re-grow through spend much longer as an egg, growth, and suitable habitat for egg-
woodland succession. Regular larva or pupa than as an adult, laying and larval development is
management provides continuity of and the habitat requirements of usually crucial. Details of individual
short-lived habitat conditions. each stage may be very different. species requirements are given in
Section 4.
Woodland management for butterflies and moths | 15
Careful planning allows you to work
Sam Ellis
out what is possible and to set
priorities. The stages are:
• Assess what you have (consider
what habitats and species are
represented, in a local and/or
regional context)
• Decide your objectives and
priorities (incorporate the needs
of butterflies and moths alongside
other interests)
• Decide how these objectives are
to be achieved over time, given
your resources and any legal
requirements (including felling
licences, site designations and
protected species)
• Monitor progress and examine how
both vegetation and your target
species respond to management
(incorporating what you learn into
future management)
Once management is underway,
be flexible and consider revising
management prescriptions if they
do not meet your objectives. It may
be best to trial new management on
only a proportion of the site, until
monitoring results show that it does
deliver the anticipated conservation
Open space as part of the wooded landscape at Whitbarrow, Cumbria outcomes.
through the landscape and between Management planning Felling licences
habitats gives them a better chance As part of the management plan it
Management for butterflies and
of adapting to future changes. must be noted that a felling licence
moths often requires a long-term
The aim should be to restore and from the Forestry Commission is
commitment to produce a diversity
construct landscape networks with generally required for the felling
of habitats that will meet the
interconnected, varied habitats. of trees, even if the work is part of
requirements of a variety of species.
Working at the landscape scale a grant scheme. Full details are
It is essential to have clear priorities
also helps share responsibility for included in the Forestry Commission
and defined aims to ensure that the
management, with each landowner booklet, Tree Felling – Getting
main objectives are not lost in the day
only needing to do a small amount Permission.
to day practicalities of management.
to contribute to the network.
Coordinating management between
Susan Clarke
multiple owners can be challenging,
however, especially where woodlands
have been split into many small plots.
The following sections detail
management practices that can
produce the diverse and dynamic
woodland habitats that best support
butterflies, moths and a variety of
other wildlife. The options can be
adapted to both small and large
woodlands, and those with primarily
conservation or commercial forestry
objectives. While the suggested
management has conservation aims,
most will also produce commercial
products such as coppice poles,
timber, firewood and other wood
Forestry operations provide a chance to improve habitat conditions whilst meeting other
fuels. objectives
16 | Woodland management for butterflies and mothsmoths
Woodland management relevant to
Dan Hoare
woodland butterflies and moths of concern
Small Pearl-bordered Fritillary
Other moths of concern
Pearl-bordered Fritillary
Silver-washed Fritillary
UK BAP Priority moths
White-letter Hairstreak
High Brown Fritillary
Chequered Skipper
Duke of Burgundy
Brown Hairstreak
Grizzled Skipper
Black Hairstreak
Purple Emperor
Heath Fritillary
Dingy Skipper
White Admiral
Wood White
Promoting
diversity of age
••••••••••• ••••••
Using wood as fuel, in the form of logs, structure
woodchip, pellets or charcoal, can
provide an economic basis for sustainable
Restoration and
management of
•••• • • ••••••
management
coppice
Managing for different Ride and glade
enhancement
•••• • •• • ••••
species
It may appear that many woodland
butterflies and moths of conservation
Canopy thinning •••• ••• • • ••
concern have incompatible
requirements. Some species
need regular woodland clearance,
Woodland edge
buffering
•••••••• •• • • ••
while others depend upon closed
canopy mature trees. This does not
normally cause problems except Reinstating
wetland features
• •
on very small sites. The following
management techniques are all
aimed at increasing the diversity of Increasing
deadwood
•
woodland structure and the diversity
resource
of foodplants for Lepidoptera. Diverse
woodlands will contain a wide variety Protection of
veteran trees
••
of habitats that will be capable of
supporting a variety of species.
The needs of closed canopy, high Restoration of
wood pasture
• •• •
forest species and those needing
early successional habitats should
be seen as complementary rather Managing deer to
reduce browsing
••• •• • •
than mutually exclusive. Where
requirements do appear to be
in conflict, particularly on small
sites, it will be necessary to assess
Replacement of
non-native trees
••
conservation priorities in a local
context. Conflicting priorities will also
be more easily addressed within a
Improving
connectivity
••••••••••• ••••••
landscape scale approach to habitat
management.
Dan Hoare
The implementation of sympathetic
management regimes aimed at
butterflies will, on the whole, deliver
conservation for many moths.
However, moths are a larger and
more diverse group than butterflies.
They exploit a far greater range
of foodplants and habitats and
additional features may need to be
considered such as the availability
of veteran trees, deadwood, fungi,
lichens and wetland features.
Butterfly habitats can be ideal for a range of other wildlife - reptiles are common on this
Grizzled Skipper site on the edge of a young plantation
Woodland management for butterflies and moths | 17
Coppice
An active coppice cycle provides a continuous succession of open
space and a varied woodland structure that can create suitable
habitats for a range of wildlife
Coppice and its history timber trees (standards). The habitats for woodland wildlife. It was
underwood would be cut on every not until the late 1800s that markets
Coppice is a system of producing
rotation but the standards would for coppice products began to
wood products that is based on the
be left to grow for perhaps three disappear and commercial coppicing
ability of trees to re-grow rapidly and
rotations to produce larger timber. In diminished. This decline continued
vigorously from their cut stumps
simple coppice, only the underwood through the 20th century: in 1947,
(stools). In coppice management,
is present and it is all cut on every 142,000ha of actively managed
trees and shrubs are cut to the
rotation. In many areas it was coppiced woodland were reported,
ground, allowed to re-grow, usually
traditional for domestic animals to compared to just 23,000ha by 2000.
with multiple stems, and then re-cut
graze within the coupes once scrub
on a set rotation. Coppicing appears By the end of the 20th century,
growth was more than about 4 years
to increase the life-span of trees, much coppiced woodland had
old, but nowadays this is rare.
indeed some of the oldest coppiced been grubbed out for farmland,
stools have been estimated as more Coppicing was the main form of development, or converted to
than 1,000 years old. woodland management over most conifer plantations. Other woods
of lowland Britain until the end of were abandoned and reverted to
Usually a coppice site will be divided
the 19th century. Its purpose was closed canopy woodland dominated
into many small areas (typically
to produce a regular crop of small by mature trees. The resulting
called coupes) and each will be cut
timber and woodland products and, woodland structure was generally
on rotation in such a way that at
where standards were grown, to less diverse and more shaded and
anytime the site will contain coupes
supply a smaller amount of larger provided little habitat for species of
of all stages of growth from newly
timber. Only recently, in the last 30 open woodland. However, since the
cut to mature. Coupes typically
to 40 years, has it been viewed as 1970s, there has been some revival
range in size from 0.5 to 3ha. The
a specialist management aimed of coppice management, often but
length of time between a cut on each
at providing nature conservation not exclusively as a tool to provide
coupe will vary with the type of wood
benefits. In particular, it has been specialist wildlife habitats. There
product required and the rate of
successfully utilised to provide the is still a small market for coppice
growth, but can be anything between
specialist open early successional products, together with a growing
3 and 50 years.
woodland conditions required number of initiatives to promote and
by some of our most threatened expand that market.
Morag McCracken
butterflies such as Pearl-bordered
Fritillary, Heath Fritillary and High The value of coppice for
Brown Fritillary. It has also been butterflies and moths
seen as an excellent management to
maintain habitat for other threatened The reduction of coppice
wildlife such as helleborine plant management has been a major factor
species, dormice and nightingales. in the decline of several butterfly
and moth species, especially the
The practice of managing woodland fritillaries. These species
woodlands as coppice may go are dependent on the habitats found
back into prehistory. Certainly, by only in the early stages of regrowth
the time of the Domesday Book in after a coppice cut, but a full coppice
1086, coppicing was widespread cycle is needed to create these
throughout lowland England. habitat conditions. A closed canopy
Coppice systems have been stage with several years of dense
Coppiced Sweet Chestnut in the Blean repeatedly modified throughout shade promotes shade tolerant
Woods of Kent provides habitat for the history in response to changing woodland flora and suppresses
Heath Fritillary markets. As timber uses changed, competitive plants. When the coppice
this drove changes in species choice, is cut once more it will then provide
rotation length, and in the proportion the open ground conditions and
Traditionally in Britain, two foodplants needed, such as violets
of standards required. However, it
systems were used: coppice with in the case of the Pearl-bordered
seems probable that whatever the
standards and simple coppice. In Fritillary. Comparatively few butterfly
system, coppicing took place on such
coppice with standards the wood species utilise the older stages of
a wide scale that it created a dynamic
contains coppiced trees or shrubs coppice growth, but all stages of the
mosaic of woodland, from open to
(underwood) and also scattered coppice cycle are of value to moths.
closed canopy, providing a range of
18 | Woodland management for butterflies and moths
For many butterfly species, the To reduce shading yet retain the
Amber Rosenthal
composition of tree species in the valuable mature tree habitat, there
coppice is not particularly important are several options. Standards can
because it is the ground flora that be grouped rather than scattered,
supplies their larval foodplants. individual standards can be situated
However, the larvae of many moth at the corners of coupes (they make
species do feed on shrub and good boundary markers) or small
tree species. The presence of tall strips of un-cut woodland can be
standard trees of different species left between coupes. These strips
will provide additional habitat. should be carefully positioned to add
shelter without excessive shading.
When is coppicing a A balance between standard quality
feasible option? and shading can be achieved by
removing some older trees and
It is probably not worth initiating allowing younger standards to grow
coppicing within established on in their place.
woodland that has no history
of that management or on sites In the long-term, some standards
where coppice has now developed should be left uncut to produce
into high forest. The response to the veteran tree and deadwood
coppice management is likely to Heath Fritillary nectaring on Bramble habitat required by many moths
be poor and these sites may have and other wildlife. Allowing some
developed fauna and flora associated Choosing simple coppice or short-lived trees such as birch and
with mature woodland that will be coppice with standards? Unless willow to become standards can
damaged by cutting. planting a new coppice, this decision produce deadwood habitat quickly in
will probably depend upon the comparison to species such as oak.
Coppicing is almost certainly history of the site. Generally when
worthwhile on sites that have a recent managing for Lepidoptera the use Rotation length: Historically, the
history of this management and that of a long rotation coppice with length of the coppice cycle and
still have a good density of stools. standards is a good choice as it the size of coupes varied between
Sites that have been extensively creates a diversity of habitats. different areas, between woods and
cleared within the last 50 years also over time. For conservation
are also likely to respond well to Number and rotation of standards: purposes, factors other than the size
coppicing. The value of standards in coppice of the mature coppice stems usually
can be enhanced by establishing a take priority. Nevertheless, if there
Coppicing may not be the best mixture of tree species and ages. If, is a commercial product which can
policy in very small woods. The area however, the aim is to create sunny make the conservation management
of potential coppice must be large coupes with a varied ground flora more sustainable, then the desired
enough to support the coupe sizes, for breeding butterflies and moths, crop size must be taken into account
the rotation/s and also the layout then the number of standards when deciding both rotation lengths
of age classes needed to meet the must be strictly limited. One of the and coupe size.
management aims. For example commonest reasons why coppicing
cutting a coupe size of at least 0.5ha fails to supply good butterfly habitat The value of mature coppice stages
per year under a rotation of 7 or 8 is that too many standards are for moths must not be forgotten in
years will require an overall coppice present producing too much shade. the effort to produce open sunny
area of at least 4ha. This can be a Excessive shade will also reduce areas. If a site is large enough,
problem when managing for some coppice growth and damage future then a solution can be to operate
of the fritillary butterflies. Although coppice viability. It is most important predominantly short rotations of less
the butterflies require a continuous that the total canopy cover of than 10 to 15 years but retain a series
supply of newly cut areas, the standards is no more than about 10 of coupes that are cut on rotation of
coppice must still go through a to 15% of the coupe area. 20 years or more. Sufficient young
long enough rotation to shade out coppice can then be produced while
vegetation as explained above. This The appropriate number of standards also ensuring that a certain amount
problem can be overcome by cutting will depend on their canopy cover, of old coppice is always present.
every other year, or by coordinating as each tree species produces a
management across a group of different canopy area when mature. Ideally at least one coupe should be
adjacent woods as one unit. It should also be noted that the cut every year, but if labour is short
shade cast by trees in leaf is often or if the wood is too small to support
Coppice structure and layout underestimated because most a full rotation, then a compromise is
management is carried out in the to cut a larger area every two or three
Where coppicing is appropriate,
winter, and that young specimens years.
the following factors must be
considered to make it successful and will quickly expand their canopy size
sustainable: once in an open situation. Generally
15 large standards per hectare
should be the absolute maximum
when managing for butterflies.
Woodland management for butterflies and moths | 19
Advantages and disadvantages of different rotations: Avoid creating narrow coupes, unless
it is part of management along a
ride edge. These are likely to have
Short rotations the same problems with shading,
encroachment and browsing damage
Advantages Can maintain the supply of young growth areas, as small coupes. Aspect will affect
often better for butterflies the amount of sunlight falling on
Disadvantages Labour-intensive in large woods the coupe, and north or east-facing
In some cases may be too short for the underwood coupes may need to be larger to
to be of commercial value allow light to penetrate.
May not supply habitat for species that require On a practical level, it is a good idea
older coppice to mark out the corners of every
Growth may not get dense enough to shade out coupe with permanent posts or by
the ground flora pollarding trees, and to produce a
map of the proposed coupe rotation.
Medium to long rotations The length of most coppice rotations
Advantages Longer rotations create a wider range of habitats means that the people doing the
than short, often better for moths cutting will probably change from one
cycle to the next, so markers and a
Can make coppicing economically viable in
map will be needed to guide future
large woods
management.
Disadvantages In some cases may be too long for the underwood
to be of commercial value Common failures
Can be difficult to maintain the supply of young and problems
growth areas
• Initiating management without
defining the aims and objectives
Size of coupe: For the coppice- year, although a larger area is needed • Underestimating the resources
dependent Lepidoptera, the advice for the habitat to be rotated through needed. Work is abandoned during
is not to cut less than 0.5ha per year the full coppice cycle. the rotation because of labour
per site. The main factor is to achieve shortages
the minimum area of breeding habitat Layout: When selecting the coupe • Short-term planning. Rotational
required to support a population areas, any special, legally protected coppice will not deliver
of the target species. This will be or locally unique features and habitats conservation unless a long-term
provided by the most recently cut that might be damaged or removed commitment is made to continue
coupe together with a number of the by coppicing should be retained. For the management for many years
previously cut coupes depending example, stands of mature Aspen
• Isolation. Habitat created is too
on vegetation development. The are uncommon and have high value
distant for the target species to find
appropriate flora needed for a for specialist invertebrate species,
and colonise before the habitat is
species such as Pearl-bordered including moths. Retain any special
lost to succession
Fritillary is very likely to exist only or uncommon trees, veteran trees or
old pollard specimens. • Sites or coupes are too small to
in small patches within any single
provide a sufficient area of breeding
coppice coupe and this must be
Coupes are best situated next to habitat. Suitable ground flora fails
taken into account.
flower-rich sunny rides. These will to develop on otherwise suitable
The total area cut each year can supply nectar, act as a seed reservoir, coupes
be divided into as many coupes as provide insect flight paths between
Mark Parsons
required, but single coupes of less coppice areas and also allow access
than 0.5ha are usually too small to when cutting. For butterflies, it is best
supply suitable unshaded, early if coupes can be cut sequentially
growth habitat. They are generally with areas cut in subsequent years
shaded by adjacent woodland being no more than 300m away. This
and are quickly encroached by the is essential for many of the butterfly
established vegetation at the coupe species dependent on early stage
edges. Small coupes are often heavily coppice as they are often poor at
browsed by deer and rabbit, as these finding and colonising new areas.
animals prefer not to venture far from
Cutting slightly irregular coupe
cover so avoid the open spaces of
boundaries will increase the edge
large cut areas.
habitat and may be beneficial in
Surprisingly, if the habitat is suitable adding another variation in structure
then many butterfly species can have to the woodland landscape. For the
viable populations within only 1 to same reason areas or small strips The Common Fan-foot is often associated
of uncut woodland can be retained with rotational coppice management,
2ha of coppice habitat within any one although it probably breeds on oak
between coupes, but avoid shading
standards rather than the underwood
the coppice. species
20 | Woodland management for butterflies and moths
• Leaving too much shade. Typically
Dan Hoare
too many standards are retained, or
coupes are too small
• Re-cutting before allowing the
coppice to go through the full
cycle. Re-coppicing part way
through the cycle is sometimes
attempted as part of emergency
conservation measures for
particularly threatened early
succession species. This rarely has
the desired result of restoring the
early successional ground flora and
tends to result in a uniform grassy
sward of little value to the target
species. The closed canopy stage
is essential
• Excessive deer or rabbit browsing.
High levels will damage or prevent
regrowth. Damage may be reduced
by cutting large coupes, as deer
and rabbits prefer to be close
to cover. It may be necessary to
protect individual stools or fence
entire coupes through the stage
of young growth (see “Managing
deer” for a more detailed
discussion)
• Damaging the site during cutting
and clearing. Use as few bonfire
sites as possible. Locate them
carefully where they will not A coppiced Sweet Chestnut stool showing vigorous regrowth two years after cutting
damage stools or other habitats
such as flower-rich grassland.
Re-using previous burn sites is in most practical guides to coppicing. New coppice woodland
recommended It is possible to create new coppice
Low intervention: Neglected
• Failure to monitor results and coppice could also be left to by planting or direct sowing, but
incorporate successes or failures eventually take on the characteristics unless the area has been wooded
into future management of a natural forest. In this case, it in the very recent past then creating
might be worth thinning some of the suitable flora required by many
the coppice by singling, that is by of the woodland Lepidoptera may be
Restoring neglected difficult. Many species of butterflies
removing all but the best stem on
(over-grown) coppice each stool. This is generally used and moths will also have problems
The choice of management in to try and produce good quality colonising a new coppice if it is
neglected coppice (sometimes timber but in the context of habitat for any distance from their existing
called stored coppice) is either Lepidoptera it is likely to speed up populations.
to re-coppice, to manage as low the creation of large mature trees that
intervention (leave to develop to If new coppice woodlands are
will provide additional structure and
high forest) or to clearfell and then to be created specifically for
habitat.
re-establish a new coppice or a new conservation then they are best
broadleaved woodland. Clearfell and replant: Another sited next to existing semi-natural
option is to clearfell the overgrown woods, otherwise it will be difficult
Re-coppice: The choice to re- coppice and replant with native trees to establish the suitable woodland
coppice will depend on the time at fairly broad spacing, allowing the flora and fauna required by the rarer
since the last cut, the condition and underwood to regrow as shrub layer. Lepidoptera.
density of the stools. Many sites with The site can then be managed as
overgrown coppice have shown a The creation of new, short rotation
either coppice with standards or left
surprisingly good response to re- simple coppice for biofuels is now
to develop as mature woodland. In
cutting, although stool density may being actively promoted (mainly
general, this option seems to carry
have to be increased by planting willow or poplar species). It is not
few benefits for conservation over
or by encouraging vegetative yet clear if this process will hold
re-cutting. It is expensive in cost
propagation. Techniques for creating any benefits for the conservation of
and labour and importantly unless
new stools from the old stumps such Lepidoptera.
small areas are clearfelled on a long
as layering and stooling, as well as rotation the risk of damage to the
re-spacing the stools, can be found existing flora and fauna is high.
Woodland management for butterflies and moths | 21
Rides
A ride is any linear track or opening within the wood and includes
the whole area between the mature trees on either side. That is the
surface of the ride itself, any ditches and also the vegetation on the
ride verges (grassland, scrub or coppice regrowth).
Most woods have at least some However, this limited amount of
Dan Hoare
rides for access, shooting activities coppicing is usually not adequate on
and increasingly for leisure activities its own to maintain the very specialist
such as walking, horse-riding and early-stage species such as the Heath
cycling. In commercial forestry, rides Fritillary.
do serve a purpose as fire breaks
but are primarily to give access for Ride verges may have associated
forestry operations, including timber ditches and these give not only
extraction. As forestry machinery additional structural diversity, but also
becomes larger, some of these can be a source of wetland or damp-
rides have been surfaced to create loving plant species. The ditch banks
woodland roads. are often particularly warm, sunny
habitats.
Why are rides important for
Lepidoptera? Management of rides
For butterflies and moths, the four
In many modern woodlands
key factors are the: Herb-rich vegetation in ride edges
(particularly in conifer plantations),
open areas are largely confined to provides nectar, roosting sites and larval
• amount of shade foodplants
rides and glades and these have
• structure of the vegetation
become a refuge for the butterflies than those orientated north to south.
and moths that need open sunny • species composition of the ground- As a rough guide, ride width must
conditions. Some of these species layer vegetation be 1.5 to two times the height of the
are woodland or wood edge • species composition of the ride surrounding trees to provide good
specialists, but many will also be edge trees and shrubs unshaded butterfly habitat (width is
found in the wider countryside. Rides measured from the base of the crop
also usually provide the best way of Although open sunny rides with less trees on either side). There can be
connecting different habitats within than about 20% direct shade are scrub growth within this width as this
woodlands, and prevent species required by many butterfly species, tends to have only a slight shading
having to move through unfavourable other Lepidoptera (including some effect.
conditions to reach the next habitat butterflies) prefer partially or even
patch. Providing these areas can heavily shaded areas. Thus a variety Along some ride networks there may
be suitably managed, their value for of shade conditions and similarly a be a constant mix of different tree
Lepidoptera can be enormous. range of ride widths and orientations heights with many patches of low
will need to be produced and growth and in such cases the width
Rides potentially provide a large and orientation will be less important.
maintained. Even a single species
diversity in structure and vegetation
will require a range of rides to meet Practical methods for achieving the
within a small zone. They combine
its requirements under different required ride structure are given
sheltered grassland with typical wood
conditions. For example, the Wood below. First the rides might need
edge habitat and this can provide
White tends to use areas with less to be opened up or even created,
diverse areas of nectaring and
than 20% shade, but one study then consideration must be given to
breeding. On many sites they also
suggests that it not only moves ongoing management.
contain relics of habitat types that are
between rides of different orientations
now scarce in the wider countryside
during the day following the sun,
(for example; unimproved grassland,
but also on windy days it chooses
Widening existing rides
wetland habitat, heathland) and so Often the first priority in a wood is to
sheltered but slightly shady rides,
can support the associated butterflies increase ride width to reduce shade
over the open sunny rides.
and moths. levels. However, this should target
The amount of shade on a ride will be areas with simple structure and dense
When rides are managed with a
determined by its width, its orientation crops close to the ride, to avoid
scrub-zone cut as coppice, then
and the surrounding tree height. East damaging valuable semi-natural
some of the species associated with
to west orientated rides will receive woodland and the species using the
coppice rotation will use this habitat.
more sun during summer months current ride edges.
22 | Woodland management for butterflies and moths
If left to themselves, rides will quickly
Alan Reid / Forestry Commission
revert to high forest. In order to
create and maintain diversity active
management will be required.
Several cutting regimes have been
developed to specifically meet the
needs of butterflies and moths: -
Two zone system: This is similar
to the rideside management used
in commercial forestry. It is low
cost, low maintenance, but also
comparatively low in structural
diversity. It does not produce the
good scrubby margin needed by
many moth species, although under
some rotations, patchy scrub is likely
to develop. It can provide good open
grassland habitat for butterflies.
Ride widening for Wood Whites at Bury Ditches, Shropshire
The central ride zone is cut once or
twice a year (unless it is surfaced) to
In conifer plantations, often the only Creating new rides maintain it as an access route.
remaining deciduous trees and
In semi-natural woodland with no
shrubs are located in a thin margin A zone (2 to 5m wide on each side)
pre-existing rides it is suggested
along the crop edge, and this will either side of the central zone is cut
that a most careful examination of
be removed by widening. Potential on 4 to 7 year rotation, but this is
the site is required before creating
damage can be reduced if only carried out in sections so that only a
ride habitat. If the site is an actively
short areas are done at a time and portion is cut each year. Importantly,
managed (or recently managed)
substantial lengths of the original the whole ride, or even all of one
pasture woodland or if it has a rich
ride edge habitat are left between side of a ride should not be cut in the
or uncommon ground flora, then
widened sections. same year.
ride creation may not be suitable.
Retain specimens or groups of As always, consider the aim of the
management and examine any Further habitat variety can be created
locally uncommon trees (uncommon by simply introducing two different
in terms of either species or age). A conflicts that the new management
might produce. cutting rotations, cut some margins
patch of Aspen for example, may be on a short rotation (4 years) and
the only breeding area on the site some on a long rotation (7 years).
Try to create wide, gently curving
for several species of moth. Sallows
rides with varying orientations along
provide an important nectar source Three zone system with coppice:
their length. Plan the routes of new
for many insects in spring and may This is a more complex regime that
rides carefully to avoid conflict with
provide breeding sites for Purple can provide an excellent mosaic of
existing features. Any special, legally
Emperor and many moths, and habitat for both butterflies and moths,
protected or locally unique features
should be retained where possible. including habitat for some of the
and habitats must be protected.
Retain any special or uncommon canopy-living species.
An often-stated objection to ride
widening is the wind tunnel effect trees, veteran trees or old pollard The central ride zone is cut once or
- the channelling of wind between specimens. twice a year (unless it is surfaced) to
stands of tall trees. This can have maintain it as an access route.
After clearing, the stumps in the
an impact on a timber crop and may
centre which will become the grass/ A zone of tall grassland vegetation is
reduce the sheltered conditions
herb zones can be removed, ground created either side of the central zone
favoured by many Lepidoptera.
down or treated with herbicide. (2 to 5m on each side). This zone
Ride layouts with curves rather than
Stumps along the margin should not is cut, in sections, on a 3 to 4 year
straight lines will not suffer from this
be treated but allowed to re-grow and rotation with opposite sides being
effect, but many woods have straight
then managed as coppice. cut in different years. As with the two
line, grid system rides. Wind damage
can also occur after ride widening, as zone system, it is important that the
wind-hardened trees on the edge are Creating and maintaining whole, or even one side of a ride is
removed, exposing weaker trees that verge habitat not cut in the same year.
are then damaged or blown down.
These issues can be minimised by The best ride edges graduate from A mixed species scrub zone (5
widening using scalloped edges so tall trees, to a variety of shrubs, to tall to 10m on each side) is created
that the ride is not uniformly wide and herb-layer vegetation then grassland between the tall grassland zone
it remains sheltered. An alternative flora. It will also include some bare and the woodland. This is managed
is to leave “squeeze-points” along ground and ideally there will be rather like coppice to provide mixed
a ride, retaining occasional mature canopy gaps and height variation ages of woodland succession. A
trees which break up the exposed within the scrub zone. rotation of 8 to 20 years is suggested
profile. and as with the adjacent zone, it is
Woodland management for butterflies and moths | 23cut piecemeal.
Dan Hoare
A three zone ride edge
As with coppice, the length of rotation
must be balanced between providing
sufficient open newly-cut woodland
habitat and allowing the regrowth to
shade out the ground vegetation so
that sparse vegetation/bare ground
conditions are produced after each
cut. The ideal cutting rotation will
depend on the growth and density of
the scrub. If scrub density or species
variety is poor then the zone can be
planted, or temporary fencing can
be used for protection while tree
seedlings establish naturally.
Each section can be 50-100m in
length dependent on the size of the
woodland, and both section length The three zones of a south-facing ride edge in a Hampshire woodland. The central ride
zone (at right in this image), cut once a year, is grassy but holds plenty of herbs and
and cutting rotations can be varied
bare ground, supporting Grizzled Skipper. The tall grassland zone, cut every 3 years,
across a woodland. has a mixture of bracken, herbs and grasses, and at this site supports Pearl-bordered
Fritillary. The mixed scrub zone at the back, cut as coppice, is predominantly birch and
Further enhancements to provides breeding sites for Argent & Sable.
basic ride management
The following can be used along or to produce patches of early
rides and forest roads in combination Including rideside native trees: successional vegetation. Varying
with the two and three zone cutting Native broadleaved trees can be a sizes of patches could be selected
systems described above, or as rare habitat in coniferous plantations. on rotation and mechanically scraped
stand-alone management: Even within mixed or deciduous free of all vegetation, making sure
woodland older trees may be that a degree of soil disturbance also
Scalloped edges: A series of uncommon. Many Lepidoptera seem occurs. Allowing scuffing or scraping
rideside bays, often called “scallops” to require mature trees that are by ride-cutting machinery can also
are created along the ride verge/ slightly separate from woodland and create bare ground habitat on a
tree boundary. These not only widen that have ground-vegetation around small scale. Small scrapes along the
the ride to reduce shading but also their trunks rather than underwood. top of roadside banks are effective
provide shelter and increase the at establishing the low growing
length of edge habitat. A few, mixed species deciduous foodplants of the Grizzled Skipper,
standard trees can be planted or left and more extensive scarification and
A suitable size, as a very rough guide, to grow in the ride margins (making rotovation techniques have been
is approximately 30 to 50m long by sure the canopy cover along a used to improve floral diversity in the
10 to 20m deep. If the scallops are rideside or within a scallop is less Brecks of Norfolk and Suffolk.
cut opposite each other then they than 10 to 15%).These trees can
provide a maximum open area, be in small groups or as scattered The timing of verge cutting: The
essentially widening the ride. They individuals. time of year and frequency of cutting
can also be staggered, alternatively plays a key role in determining the
or randomly along a ride. Bare ground areas: Many composition and structure of ride
Lepidoptera require some bare vegetation, but this is also affected
They can be managed to produce ground patches to provide the by soil type so the effect will vary
one of two habitats, scrub or suitable hot-spot microhabitat around between sites. Cutting at any time of
grassland, the difference is in the their foodplant or for basking. It also year, whatever method is used to cut
frequency of cutting. A scrub scallop provides structural diversity as well as and remove material, is very likely
is managed on a coppice-style floral diversity by encouraging seed to affect or destroy some life stages.
rotation in the same way as a scrub germination. Several larval foodplants It is therefore important to only cut
zone in the three zone system. A for scarce Lepidoptera are associated part of the verge in any one year and
grassland scallop is managed on the with regular ground disturbance, such to monitor the impact on any target
same system as the tall grassland as Wood Spurge which supports species. If the only breeding area
zone in the three zone system. the Drab Looper moth. Activities or for a species is in the portion due to
managements that regularly result be cut that year, consider whether
Scallops can be used as a
in areas of bare ground can be most cutting can be delayed to allow
management in its own right or
useful, as long as they only affect a colonisation of nearby habitat.
incorporated to add extra diversity
part of the habitat in any given year.
within a three zone system (see case
study “Chiddingfold Forest”). It can sometimes be useful to
create areas of bare ground under
controlled conditions, to perhaps
encourage seed germination
24 | Woodland management for butterflies and mothsGeneral recommendations are as Combining conservation will regularly remove all breeding
follows: habitat along the road edge. Timing
management with forestry forestry operations to the needs
Cutting grassland vegetation: operations of Lepidoptera is also not usually
Cutting during the autumn is usually Forest roads are maintained to allow possible, although often some
recommended, to avoid damage good access for forestry machinery compromise can be reached. It is
while insects are most active in so they are usually wide and kept therefore vital that similar habitat
summer, and to allow plants to set clear of overhanging canopy. This is available within a more secure
seed. In the past, however, most also means that they can have high location. If there are no refuge
rides would have been maintained potential as Lepidoptera habitat. habitats nearby to provide continuity,
either by grazing or by cutting for However, a forest road with its then local extinction of species is
hay in July or August. On particularly verge is a working environment and highly probable.
fertile sites with strong ground-flora conservation management needs
growth then some cutting during to take this into account. If forest Features such as turning circles
July or August could be considered, roads and associated features are and loading bays can, like the road
as there is evidence that this not maintained efficiently, then their edge habitat described above,
encourages a broader range of flora. maintenance incurs extra cost. provide good breeding habitat for
Alternatively, some cutting during the species requiring sparse vegetation
spring or very early summer would Many are managed on a similar and bare ground, but this habitat
remove early grass growth yet still cutting regime to the two zone will be damaged or destroyed at
allow many species to flower later. system. The alternative three zone intervals. This is also the case for
system can result in vegetation most roadside ditches, created to
Spring or summer cutting may be encroaching on the road surface take the run-off from the surfaced
beneficial in the long-term but will as might occur on a 3 or 4 year roads. These ditches, their banks and
temporarily remove some breeding rotational cut. In this case a slightly associated vegetation can provide
habitats and nectar sources. This modified three zones can be used habitat for species such as Wood
issue can be limited by only cutting a whereby the central zone is moved to White, but they will be regularly re-
small proportion of the site each year. a narrow strip (1 to 2m on each side) dug, with spoil removed to the ditch
Whatever cutting period is decided, it along either side of the road surface. banks or verge edge.
is worth building a degree of variation This strip can then be maintained
into the management because by annual or more frequent cutting. Forestry activities can have an impact
different plant species will respond For ease of mowing, this strip can on verge habitats, for example where
to different regimes. Deciding the additionally be cut whenever the vehicles use the verge during timber
timing, frequency and rotation of adjacent zone of tall grassland flora extraction or where wood is stacked
cutting, together with an aim of what is cut. on the ride edge. Minimise impacts
structure you are trying to create, is by:
more important than defining precise Essential forestry operations may
cutting heights. have significant adverse impacts on • Ensuring that the entire ride
Lepidoptera breeding areas along network is not managed uniformly
It is best to remove the cut material rides. The road/verge edge tends in any one year
if at all possible (some forage to receive regular disturbance as • Providing refuge breeding areas for
harvesters can cut and gather the all operational forest roads have the species that may be affected
vegetation in one pass). Cuttings or a periodic maintenance (grading) • Monitoring breeding areas used
mulch can smother the remaining during which this zone is scraped by susceptible species so that
vegetation and increase nutrient back to bare ground. This regular potential problems can be avoided
build-up which will reduce floral ground disturbance often provides or mitigated
richness. Cuttings can be raked into good breeding habitat for species
heaps, but these must be carefully • Protecting sensitive areas with
such as Grizzled and Dingy Skipper
sited to minimise the effect on the temporary fencing during forestry
but road grading cannot usually
rideside vegetation. Blowing or work
be carried out piecemeal and
raking the material into the adjacent
crop can be considered in coniferous
Dan Hoare
woodland, but within deciduous
woodland (or where there is a
managed rideside scrub zone) this
would cause damage to the ground
flora under the canopy.
Cutting scrub vegetation: Ride
edge scrub zones should be treated
like coppice and are best cut during
the winter. The section on coppice
includes advice on the disposal and
burning of cut material.
A wide sunny ride provides ideal breeding conditions for Pearl-bordered Fritillaries at a
Forestry Commission site in Sussex
Woodland management for butterflies and moths | 25Glades
Woodland glades are permanent or semi-permanent areas that
contain few or no trees but are surrounded by woodland. They are
usually non-linear, in contrast to rides and wayleaves, and are distinct
from young plantations or clearings containing young woodland.
Why are glades important for suitable ground flora and also the
Dan Hoare
movement of Lepidoptera into these
Lepidoptera? new habitats.
Glades provide a larger area of open
habitat than is found in rides, which Management of glades
may be important for the colony
Glades can be treated in the same
structure of some butterflies. Several
way as rides to provide a range
species can reach high population
of vegetation types, from open
densities in glades but will only
grassland through to scrub. A scatter
ever occur in rides in low numbers.
of tall trees can also add diversity, but
The Marsh Fritillary, for example,
restrict canopy cover to less than 10%
rarely breeds on rides even when its
of the glade area.
foodplant is abundant, but will use
damp grassy woodland glades of at The specific management will depend
least 1ha, and does best when there on the permanency of the glade.
are a series of such glades. A glade can be a temporary open
space, that is cut and then allowed
Creation of glades to re-grow, or a more permanent
Glades can be created either linked opening where regrowth is controlled
to the ride complex, or separate and or suppressed. Scrub cut on rotation within a permanent
glade provides a varied age structure and
located within the mature or semi- sheltered conditions
mature woodland. Overall the same If the glade is to be managed as
principles of width, shading and crop a temporary open space then the
also as small patches scattered
height apply as discussed for rides, habitat produced is similar to that
across the glade. This can be
also the same concerns for cutting created under coppice. Open bare
enhanced using irregular, piecemeal
new glades within natural or semi- ground conditions will dominate at
cutting of the patches of scrub on
natural woodland. Glades linked to first, regrowth then produces scrub
anything between an 8 to 20 year
ride systems are better connected to and finally mature woodland. Such
rotation, depending on the rate of
the wider habitat network, whereas a light to shade cycle will maintain
growth at the site.
glades within mature woodland may the typical woodland flora and will
be more isolated and difficult for prevent the vegetation becoming On a box junction, each corner
some species to locate. grass dominated. section could receive a different
cutting regime. Some cut every 1
As part of the ride complex: With Management of true permanent open
to 4 years to create grass and herb
minimal tree removal a good sized space in woodland has much in
dominated vegetation. Others cut
glade can be created by simply common with unimproved grassland.
on a rotation longer than 4 years to
enlarging the intersection of two Repeated cutting, mowing or grazing
allow the development of scrub. If
rides to produce a “box junction” will be needed to prevent scrub
the rotation is long enough to allow
or “corner glade”. Usually all four growth and without a period under
the scrub to shade out the ground
corners of the junction are removed, dense canopy shade the vegetation
vegetation, then after re-cutting,
but sometimes only two and the usually becomes grass dominated.
valuable early successional woodland
different segments to the glade do habitat can be created for species like
If large enough, then a mixture of
not have to be the same size. Pearl-bordered Fritillary.
permanent and temporary open
Separate from the ride complex: space can be created across the
On some sites there may also be
It can involve a considerable felling glade. Such a mosaic habitat
an option of using domestic grazing
of timber to create a suitably sized structure is highly attractive to many
animals within enclosures. Grazing
glade. Generally glades should be Lepidoptera and mimics that found
creates a very different type of
at least 0.25ha and preferably 0.5 to along a natural wood edge. The
vegetation from cutting, so adding
2ha in size. Grouping glades within grassland areas could be cut on short
diversity. Grazing is more practical in
the same area and providing some rotations (1 to 4 years) and some
woodland glades than rides and was
connectivity with an existing open scrub could be allowed to develop
often the traditional management.
feature will aid the establishment of not only along the wood edge, but
The aim would be to create diverse
26 | Woodland management for butterflies and mothsSusan Clarke
A large permanent glade among planted conifers
vegetation, while preventing or To save expense, often only the south-facing edges and rotational
reducing the growth of scrub and tallest scrub (that which will breach cutting of sections rather than
trees. Rotational grazing can give a clearance thresholds) is cut at any uniform management. An alternative
high level of control because stock one time. This can create a mosaic is to cut and treat stumps to create
can be moved periodically around a of small scrub of various ages more permanent open areas,
single large glade or from glade to together with open, cleared areas. although this will require similar
glade. Grazing is discussed in more It is often the only habitat of its type management to a ride or glade to
detail in the following pages. within the woodland and can be maintain floral diversity.
excellent habitat for Lepidoptera. In
Wayleaves Scotland, for example, wayleaves are
extremely important as habitat for Rob Petley-Jones
Wayleaves are the areas beneath
power lines, and within woodlands the Chequered Skipper and Pearl-
these areas are regularly cut to keep bordered Fritillary in otherwise dense
scrub/tree growth away from the plantations or regenerating native
cables. This effectively means that woodland.
wayleaves within woodlands are
The management of wayleaves
linear glades managed on a short
is often outside the control of
coppice rotation, which can provide
woodland managers, but if scarce
important wildlife habitat and improve
butterflies or moths are known to
connectivity between other open
be using the site it is worth passing
areas. Widths vary, but most are
on specific recommendations to the
10 to 20m wide. They are typically
power company. Where pipelines
managed by the power company
are buried beneath the surface the
or a contractor, whose objective is
area above may also be kept clear
to keep any vegetation a minimum
to allow access and prevent root
distance away from cables and other
damage, providing very similar The moth Anania funebris breeds on
equipment. This means that rotation
habitat opportunities. Best practice Goldenrod in glades, rides and wayleaves
lengths are not set, but depend on
wayleave management is similar to
the height of the cables and the
ride management and includes the
growth rate of the scrub.
creation of scalloped edges along
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