Seeded or turfed standard grassed areas must be planted in accordance with clause 3005 of the Manual of Contract Documents for Highway Works and Appendix 30/5 of the council’s Specification.
Conservation verges
Conservation verges can be an attractive feature within a development and provide valuable resources for wildlife but need special consideration if they are to succeed in the long term.
Most wildflowers thrive in in low nutrient soils. Suitable soils might be found in subsoils from site excavations, reducing the need to import and export materials. Plant species such as yellow rattle, where site-appropriate, can help to reduce nutrient levels in soils. However, trees and other landscaping may require alternative planting conditions, and this will need to be considered as part of the scheme design. The planting of wildflower species that can tolerate higher nutrient levels or non-native wildlife friendly species can be an option, particularly in urban sites.
Where appropriate, the retention and translocation of existing grassland of conservation value is preferred over introduction of new wildflower planting. For new planting, choose species that are appropriate to the site – there are wildflowers for every aspect and every kind of soil. Try to source wildflower seeds that are common and characteristic to the local area to help boost local populations. Details of native wildflowers can be found using the National Biodiversity Network’s database.
Specialist nurseries should be able to provide advice on suitable seed choice. Plantlife provide some helpful guidance on the design and maintenance of highway verges.
Specialist maintenance requirements
The developer must provide details of maintenance requirements, including costs, at the earliest possible stage before a decision can be made regarding the council’s adoption of new highway. Commuted sums for the maintenance of conservation verges will be calculated on a site-by site basis.