Planting is often used to establish woodlands and hedgerows because local authorities, managers, designers, developers and gardeners want woodland cover in the shortest timeframe possible.
There are a number of alternative methods of establishing woodland which are considered more ecologically appropriate, and which are generally considered more cost effective. However, vegetation may take longer to establish utilising these methods compared to the planting of ‘standard’ trees (over 175cm tall with a girth of at least 4 – 6 cm) or ‘semi-mature’ stock (trees with a girth of between 16 and 25 plus cm). These methods include the planting of ‘transplants and whips’ (between 40 and 100 cm tall), (Collins et al., 2011) natural recolonisation, direct seeding and the use of sods and plugs.
A planning condition or mitigation measure to screen a development, through planting, is one of the main reasons why the planting of standards and semi-mature stock is often required. It should be remembered that while screening maybe a requirement at a particular location, it is generally not a requirement throughout a proposed development, therefore, other methods of establishing vegetation can and should be utilised in these areas to meet ecological standards and reduce the costs of establishment.
Prior to selecting the appropriate habitat type for planting, it is important to examine the soil type within a site. Nutrient rich topsoil is generally suitable for the establishment of most trees and shrubs, tree-lines and hedgerows. The pH and fertility of the soil will vary depending on whether the soil is derived from limestone (base-rich) or siliceous parent material such as shale, granite, sandstone, etc. (base-poor) and/or where it has been augmented by liming.
Further information on planting schemes, species and densities can be found in:
- the Native Woodland Scheme Manual, 2011
- Little, et al., 2008b and
- National Roads Authority, 2006.