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Beds are an interesting mix of bushy growth for ground cover and exotic planting. Photo Alex Williams |
Exeter University has an extensive botanical collection dating from the last century and demands that the grounds reflect the traditional architecture and stature of a long established university. Mr Scarr introduced a system of grounds maintenance that virtually eradicated the use of pesticides some 10 years ago with great success.
The university covers 166 hectares of which 104 hectares are gardens. The main reason for discontinuing the use of pesticides was to protect the significant botanical collection but the move has also brought many environmental benefits. The chemical dependency cycle has been broken and the number and variety of wildlife species has increased. The site supports 60 species of birds, 21 butterfly species and mammals including deer, badgers and foxes.
The management strategy emphasises the importance of maintaining healthy soil and plants. The significant reduction in pesticide use has been achieved by ensuring that bare soil in beds and borders is covered by a combination of dense planting, mulching and by selecting disease resistant plants.
Disease on lawn areas has been reduced by a meticulous and increased mowing regime. Regular mowing reduces the bulk of clippings which are left on the surface to act as a natural mulch and are quickly assimilated into the soil. Despite regular mowing a longer sward is tolerated to maintain plant vigour. Occasionally it is necessary to remove clippings which are then composted on site.
Mr Scarr admits that non-chemical control demands a great deal of courage. When heather is first planted it tends to turn brown but when left for a while recovers and becomes vigorous. Two cricket pitches were recently planted and left to become established without the use of fungicides. He admits that he becomes nervous at the sight of fungal diseases like fusarium but has found that the selection of suitable grass species, combined with a healthy soil, successfully combats the patches that do appear from time to time. Fusarium did appear on the new cricket pitches but disappeared over time. Fungal-resistant roses are planted to reduce the need for chemical control. Standards of pest tolerance are in place but the ecology of planted habitats keeps populations under control.
The lawns support ‘weeds’ such as daisies and buttercups which are considered to enhance rather than denigrate the aesthetic appeal. A bank in front of one of the buildings supports a thriving community of orchids which add colour and are resistant to mowing when not setting seed.
Bark mulch is produced from natural pruning. Conifer mulch is produced and used in abundance supporting the conditions required by acid loving plants including rhododendron and azaleas. Many of the beds are planted with heather and moorland species providing effective ground cover whilst reflecting the natural flora of the area.
The grounds are aesthetically pleasing and although undoubtedly well cared for have a ‘natural’ look. The practice of clearing some of the vigorous areas and inter-planting with younger or lower growing plants reflects the natural moorland mosaic habitat.
Although expensive, biological control is found to be extremely efficient in the greenhouses, supporting a variety of tropical and sub-tropical fauna. A schedule is worked out and revised annually alongside regular pest monitoring.
The success of Exeter could certainly be repeated elsewhere in the country across a wide range of facilities from municipal parks to sports and amenity centres.
(AW)
[This article first appeared in
Pesticides News No. 52, June 2001, page 19]