FBI Prescription Sets: Duke of Burgundy

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Farmland Butterfly Initiative
Target species information – HLS options and Indicators of Success
Duke of Burgundy – Feature description
s41 Priority Species. Occurs in two main habitats: woodland clearings and calcareous grassland with scrub
or topographical shelter. The key requirement is for swards containing Cowslip Primula veris and/or
Primrose P. vulgaris growing amongst tussocky vegetation or along the edge of scrub, in medium to long
turf (5-20cm tall). On sites with both species, Cowslips are the preferred foodplant. Light to moderate cattle
grazing from late summer to winter may be the most suitable regime for long-term maintenance. Regular
summer sheep grazing, or heavy sheep grazing at any time is detrimental.
Relevant HLS Options
HK06
Maintenance of species-rich, semi-natural grassland
HK07
Restoration of species-rich, semi-natural grassland
HC15
Maintenance of successional areas and scrub
HC16
Restoration of successional areas and scrub
HK15
Maintenance of grassland for target features
HK16
Restoration of grassland for target features
HR01
Supplement for cattle grazing
HC07
Maintenance of woodland
Prescription guidance for HK06/HK07
In year [1 to 5], follow a programme (agreed in writing with your NE adviser) of rotational scrub
management. Never manage more than [30%] of the site in any one year and never completely eradicate
scrub from the site.
[From year 1], manage the sward by [grazing, preferably with cattle] to achieve a sward height of [ranging
between 5cm and 20cm in April / June and at least 10cm over the winter].
Manage the grassland to achieve the indicators by [extensive grazing with cattle late summer to winter] at a
maximum density of Xlu/ha.
Indicators of Success for HK06/HK07
[By year 2], the average sward height between [XX and XX should be around 10cm ranging between 5cm
to 20cm] in spring before closing for hay.
[By year 2] one or more of species [bugle, daisy XXXX or other popular nectar plants] should be in flower
during May and June, and at least [occasional] across the target area.
The extent of the [Duke of Burgundy breeding area, xha] of interest within the [grassland / scrub] as
identified [in the Farm Environment Plan / Management Plan / during the Natural England visit or add
specific site information where relevant here] should be maintained or increased.
In all years, populations of [Duke of Burgundy] should be maintained.
[By year XX], cover of wildflowers in the sward (excluding undesirable species but including rushes and
sedges), should be between [30% and 90%]. At least [50%] of wildflowers should be flowering during [MayJune].
[By year 2 / 5], cover of invasive trees and shrubs [Sycamore / Blackthorn / Cotoneaster / Bramble / XXXX]
[but excluding Bog Myrtle / Juniper / Creeping Willow / XXXX] should be less than [20% but greater than
10%, can be <10% if topographical shelter present].
[By year 2], species [Primula should be frequent within the sward between 30% and 100% with some being
large prominent plants]
By year 2], cover of [Primula should be frequent within the sward with at least 50% in flower during April –
June]
Prescription guidance for HC15/HC16
In year [1 to 5], follow a programme (agreed in writing with your NE adviser) of rotational scrub
management. Never manage more than [30%] of the site in any one year and never completely eradicate
scrub from the site.
Graze lightly with [cattle from mid/late summer to winter; light winter sheep grazing may be acceptable] in
years [1 to 10] to maintain areas of [medium height swards (with a minimum sward height of 5cm)
interspersed with taller tussocks (up to 20cm) over 80% of the site]. Avoid poaching by managing stock
carefully when ground conditions are wet.
Indicators of Success for HC15/HC16
[By year 2] one or more of species [bugle, daisy, XXXX or other popular nectar plants] should be in flower
during May and June, and at least [occasional] across the target area.
[By year XX], the following desirable species [Primula] should be [frequent within the sward with a least
50% in flower during April – May].
By year XX], the following desirable species [Duke of Burgundy] should be [maintained].
[By year XX], cover of shrub species [Juniper / Box / Hawthorn / Blackthorn / XXXX] should be between
[20% and 50%] of the area. The vegetation within [1m] of the edge of the scrub should be taller than 30cm.
Prescription guidance for HK15/HK16
[From year 2 onwards,] manage the sward by [grazing with cattle, light winter sheep grazing may be
acceptable] to achieve a sward height of between [5cm and 20cm] during [April and May] (unless the land
has been shut for hay) [and between 10cm and 20cm in November].
Rabbits must be controlled to achieve the indicators. Where this is impractical due to the nature of the land,
the numbers of grazing livestock must be adjusted to take account of this change to grazing pressure.
In year [1 to 5], follow a programme (agreed in writing with your NE adviser) of rotational scrub
management. Never manage more than [30%] of the site in any one year and never completely eradicate
scrub from the site.
Indicators of Success for HK15/HK16
[By year XX], at least [2 high-value indicator species one of which should be Primula for BAP grassland
habitat XXXX should be frequent and 2 occasional] in the sward.
[By year 2], species [Primula should be frequent within the sward between 30% and 100% with some being
large prominent plants]
[By year 2 / 5], cover of invasive trees and shrubs [Sycamore / Blackthorn / Cotoneaster / Bramble / XXXX]
[but excluding Bog Myrtle / Juniper / Creeping Willow / XXXX] should be less than [20% but greater than
10% unless topographical shelter present].
In all years, populations of [Duke of Burgundy] should be maintained.
[By year 2] one or more of species [bugle, daisy, XXXX or other popular nectar plants] should be in flower
during May and June, and at least [occasional] across the target area.
Prescription guidance for HR01
Cattle will be the [main] grazing species [during the year, ideally from late summer to winter; regular
summer sheep grazing or heavy sheep grazing at any time is detrimental]. They will comprise [at least
70%] of the livestock unit grazing days on the parcel.
Prescription guidance for HC07
Maintain open features, including rides and glades.
Indicators of Success for HC07
A network of rides and open ground should cover between [10% and 30%] of the area.
Further Information
Occurs in scrubby grassland and sunny woodland clearings, typically in very low numbers. Adults fly from
April until late May. The adults rarely visit flowers and most sightings are of the territorial males as they
perch on a prominent leaf at the edge of scrub. The butterfly has declined seriously in recent decades and
is reduced to around 100 sites.
Two principal habitats are used: chalk or limestone grassland, with either extensive areas of scrub or
topographical shelter; or clearings on ancient woodland sites, either regenerating coppice, young
plantations, sizeable glades or wide rides. In both habitats it requires foodplants growing among tussocky
vegetation of 5-20 cm. On downland it prefers north- or west-facing slopes, or sites with frequent scrub,
possibly because the humid conditions encourage lusher growths of the foodplant. The main foodplants are
Cowslip and Primrose. It occasionally uses the so-called ‘False Oxlip’, the hybrid of these two Primula
species.
Eggs are laid on the underside edge of foodplant leaves, usually in small batches of up to 8. Females tend
to select plants that are prominent amongst the surrounding vegetation, though smaller plants can be used
where they grow abundantly on calcareous downland. The larvae feed at night and produce distinctive
feeding damage on the leaves comprising a peppering of small holes, leaving the midrib and main veins
intact. They strongly favour green foodplants and wander away from exposed plants before the leaves
begin to yellow and wither. The larvae can wander several metres from plant to plant, eating small Primula
seedlings on the way. They pupate from mid-July to early August, usually well concealed, 2–5 cm above
ground, among dense tussocks of fine grasses where they pass the winter.
Chalk and limestone grassland habitats
Aim to maintain a mosaic of open, sunny grassland with abundant Primula in medium height swards (520cm), with scrub edges or patches comprising up to 20% of the grassland area. Maintain taller vegetation
for breeding and shorter vegetation to ensure continuity of foodplant supply.
Grazing
Extensive light cattle grazing is ideal. Light to moderate cattle grazing from late summer to winter may be
the most suitable regime for long-term maintenance. Regular summer sheep grazing, or heavy sheep
grazing at any time of year is detrimental, as this produces an unsuitably tight sward with low foodplant
density. Where there is no alternative, rotational sheep grazing can be used, but only up to 25% of the site
should be grazed each season. Domestic livestock grazing regimes should take account of rabbit
populations which can have a significant deleterious impact.
Scrub Control
Scrub should be cut on long rotations (e.g. 20 years) and targeted at younger, scattered scrub over relic
grassland or at bays in scrub edges. Cutting dense mature scrub is not usually immediately beneficial, as
Primulas regenerating in an open sward or amongst flushes of Wood False Brome Brachypodium
sylvaticum are unsuitable for breeding. Scrub control without grazing is rarely sufficient to maintain colonies
in the long-term.
Woodland clearings
Aim to ensure a continuous supply of clearings with abundant Primula in open, sunny conditions.
Glades
Permanent glades can be maintained by controlling scrub regrowth, brambles and coarse grasses,
ensuring all cut material is removed. As well as hand tools, strimmers and clearing saws, using a mower
set at 10cm every two or three years has been found to be very effective.
Coppicing
A regular cutting sequence of woodland blocks in close proximity will ensure rapid colonisation of new
habitat, particularly where open rides permit movement between clearings. Ideal conditions are provided in
woodland regrowth a few years after clearance when sheltered areas develop between coppice stools. On
thin soils or where deer browsing delays initial regrowth these microhabitats can be prolonged for several
seasons.
Rides
Breeding success is likely to be highest in east-west rides. Open rides can be maintained by short-rotation
coppice (5-8 years), cutting back the woodland edge to 5-8m depending on the vigour of regrowth. Herbrich grassland can be maintained by annual mowing or strimming.
A Factsheet (with ideal habitat management photographs) is available from Butterfly Conservation’s
website which can be given to landowners.
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