What is ‘special’ about Baron Hill Park SSSI?

Baron Hill Park SSSI has one special feature.

As well as the features listed above, Baron Hill Park has other features that contribute to the special interest. These include fungi and invertebrates associated with dead wood and bats associated with mature trees and these too are key components of the special interest of the site. Unless specified below, management of this site should aim to look after these as well as the listed features of interest.

What do we want Baron Hill Park to look like?

The site should comprise parkland with approximately 550 well-spaced mature trees/tree clumps supporting a diverse epiphytic lichen flora, surrounded by grassland. Oak should be the dominant tree species comprising approximately 60% of the total, with a range of other species including ash, lime and sycamore. Old, decaying and dead trees and timber should be retained for their lichens, fungi and invertebrates.

What management is needed on Baron Hill Park SSSI and why?

Although Baron Hill Park is an excellent place for wildlife it will only remain so if the necessary management continues. CCW’s aim is to work with you to ensure that this management is carried out.

What does this mean in practice?

There are many factors that could damage the special features at Baron Hill Park if they are not properly managed. These are the ones we regard as most important:

Maturity of existing trees and Tree planting:

The Ordnance Survey recorded 545 individual trees within the parkland (excluding woodland areas) in 1889. By 1993 only 235 remained, a loss of more than 55%. Many of the remaining trees are in poor health. There is no natural regeneration due to grazing pressure and, on the golf course, mowing.

Extensive replanting is required to restore the park and should largely reflect the original design to replicate the pattern of widely spaced individual trees and lines and clumps of trees. Lichens require new trees close enough to existing trees to permit colonization, but not so close as to cause too much shading.

Mature oaks and ash support the richest lichen flora, while sycamore also has a good lichen flora and is fast growing. A minimum 40% of the replanting should be oak (sessile or pedunculate), 20% ash, and the remainder other species, including sycamore, lime and exotics such as black walnut; any exotics planted should have bark suitable for lichen growth. Conifers do not have suitable bark for these lichens.

The retention of veteran trees is essential while replacements are maturing. Tree surgery and pollarding may be required to prolong the life of the existing trees.

Pollen sources including hawthorn, elder and roadside flowers should be encouraged, where appropriate, to provide nectar and pollen sources for parkland invertebrates.

Dead wood management

Dead and decaying wood is important for its associated invertebrates and fungi and continues to support epiphytic lichens while its bark remains intact. It should be retained and where possible and appropriate should be left standing until it falls naturally. Lying timber may be stacked, preferably in partial shade.

Grazing and stock management

Areas currently grazed should be grazed with a stocking rate of approximately 1.0LSU/ha (1 cow or 6.6 sheep = 1LSU). Heavier livestock levels cause soil compaction, especially around trees where stock congregate for shelter.

Supplementary stock feed, salt licks and water troughs should not be placed beneath the canopy or in an area extending 5m beyond the canopy of parkland trees. This will reduce tree root damage and water stress through over–enrichment (often indicated by stinging nettles) and soil compaction .

Antibiotics have a detrimental impact on soil micro-organisms, particularly fungi that have mycorrhizal associations with trees. They should only be used in response to specific problems and not as routine prophylactics. Treated livestock should be kept out of the park until the problem is cleared.

Pesticide application

Herbicides and pesticides can kill epiphytic lichens of parkland trees and should not be applied by spraying within the parkland. Herbicides may be applied by a weedwiper or similar system – subject to CCW consent.

Fertiliser application

Excessive or prolonged use of fertiliser can damage soil structure, which makes parkland trees prone to drought or waterlogging. Fertiliser drift onto tree trunks can render them unsuitable for lichen growth by changing the nutrient status. Applications should be limited to 10 tonnes of well-rotted farmyard manure per hectare once every two years. The application of farmyard manure should leave untreated buffer zones of 5m beyond the canopy of trees and should not be undertaken on windy days.

No artificial fertiliser or off-farm wastes such as creamery waste or chicken manure should be applied.

Ploughing and other groundworks

Ploughing, or any other groundworks should leave an undisturbed buffer zone at least 5m beyond the canopy of each tree.


Changes to ground-water levels as a result of drainage or failure of existing drainage can lead to stress and tree death. New or replacement drainage can only be considered if all works are at least 5m beyond the canopy of any trees.

Use of motorised vehicles

Vehicles can cause soil compaction and physical damage to tree roots and may leak oil or petrol. They should not be driven or parked beneath the canopy of mature trees.

Air quality

Lichens require clean air, with low levels of sulphur dioxide, dust or other pollutants. The maintenance of good air quality is vital to the conservation of the scientific interest of this site.


Our knowledge of wildlife is continually improving. It is possible that new features of value may appear and new management issues may arise in the future, whilst other issues may disappear. This statement is written with the best information we have now, but may have to change in the future as our understanding improves. Any information you can provide on the wildlife of your site, its management and its conservation would be much appreciated.

If you would like to discuss any aspect of your SSSI, or have any concerns about your SSSI, please contact your local CCW office.

Your local office is;

Cyngor Cefn Gwlad Cymru/Countryside Council for Wales

North Wales Region

Llys y Bont,

Ffordd y Parc,

Parc Menai,


Gwynedd, LL57 4BN,

Telephone: 01248 672500

Fax: 01248 679259