Phase 2 Botanical & NVC Surveys
A Phase 2 Habitat Survey, or National Vegetation Classification (NVC) survey, is used to identify and accurately map different communities of vegetation, so that their importance and relative distribution can be better understood.
These surveys are generally recommended where botanical interest has been identified on a site, usually after a Phase 1 Preliminary Ecological Appraisal (PEA) has highlighted the need for further survey work; in particular, these surveys are recommended if the habitat may qualify as a Priority Habitat at a national or local level, or that they are necessary to understand the condition of the habitats for Biodiversity Net Gain (BNG).
This survey tends to be used more often on large infrastructure projects, such as major roadways, wind farms, and power stations, and provides the ecological baseline for an Environmental Impact Assessment (EIA). Detailed habitat surveys are also undertaken for conservation projects, particularly when a habitat’s condition needs to be assessed, or a habitat’s suitability for species reintroductions needs to be ascertained.
The Botanical Survey Process
Phase 2 Surveys often follow on from Phase 1 and are more detailed – they are considered the ‘gold standard’ for describing vegetation within the UK. The standard survey methodology that is used to conduct these surveys is the National Vegetation Classification (NVC), which is accepted as the UK standard.
Results of a PEA may be used to initially establish habitats that are present on site; the Phase 2 surveys then develop upon this baseline data and may further sub-divide these habitat stands dependent on detailed species composition. However, not all vegetation can be classed into NVC types (such as brownfield sites, bryophyte communities etc); therefore, Phase 2 botanical surveys may be deemed more appropriate.
On-site visits are required to collect information about the structure of the site and composition of the plant communities. Detailed species lists will be produced for all NVC communities that are present.
A full Phase 2 survey takes a considerable amount of time to carry out and may not be necessary for smaller projects.
​Where botanical interest has been recorded as part of an initial site assessment, a more detailed botanical survey is likely to be recommended; this will typically consist of a National Vegetation Classification (NVC) survey.
Full NVC surveys sample each vegetation type present on site. Sampling involves using quadrats of transects, within or along which, plant species are recorded; the ground cover of each plant species is also assessed using recognised scales (such as DOMIN). Scores for frequency (the number of samples within which a species occurs) and abundance (the range of cover in samples) are compiled. The resultant data is then compared with published tables and descriptions to assign to NVC communities and, where possible, sub-communities.
April to September is the typical survey period, although timings will depend on habitat. Woodlands are best surveyed in April/May whilst grasslands between May and July.
Phase 2 Surveys
Phase 2 botanical surveys, whilst still utilising quadrats and transect surveys, will produce a less detailed botanical list than NVC. However, they will yield a more complete plant list for a vegetation type or habitat stand, including rare or other notable species, than a PEA.
Recording is often done using the quicker and more subjective DAFOR scale to note abundance (Dominant Abundant Frequent Occasional Rare). Therefore, it is often useful for site condition monitoring.
As above, surveys can be undertaken between March and October; however, you will get the most extensive results between April and August.
Planning Your Survey
Make sure you allow time to schedule your Phase 2 Botanical Survey. For more information regarding best survey timing, take a look at our Survey Calendar. These specialist surveys require botanical expertise, so it is imperative to commission reputable ecological practitioners, like Pioneer, to carry out these surveys on your behalf.
Don’t delay, get in touch today to discuss your development project.