For your woodland grazing plan, the condition of woodland habitats, open ground habitats and habitat mosaics identified in section 3 should be assessed. The result should be entered in the two 'current condition' columns of section 4a.
To carry out your herbivore impact assessment you will need The Woodland Herbivore Impact Assessment Method User Guide (WHIA). You will not necessarily need to carry out a separate herbivore impact assessment for every woodland and open ground habitat identified in section 3, providing the assessment includes stops within key habitats or habitats with key features.
If livestock can move freely between different habitats and there is no reason to suspect that they will be attracted to, or have limited access to, one rather than another, for example due the presence of fencing, then the woodland and open ground habitats can be treated as one for the purposes of assessing herbivore impact, even though the attractiveness of different habitats within the assessment area will vary according to relative palatability.
Follow the WHIA method, assessing current herbivore impacts at each of the stops in the key habitats that you have identified. Table 1 of the WHIA provides detailed guidance on how to recognise different levels of current herbivore impact, with links to a library of visual images in Table 4.
Complete herbivore impact field sheets for each stop and include an assessment of current woodland structure. WHIA table 6 provides a definition of woodland structure classes and Table 5 is a list of links to photos with examples of structure classes.
Defining whether observed damage has causes other than large herbivores
The WHIA method relates to grazing/browsing by large herbivores (cattle, sheep, deer, goats, pigs, horses). If it is not known which grazing species are present on the site field signs can be used. For information on how to distinguish between the effects of different damaging agents (animal, microbial and environmental) on young trees see:
- Distinguishing mammal damage to young trees from damage by other factors
- Distinguishing between browsing by different mammal species
- Woodland damage: Recognition of cause
Within the WHIA guidance notes there are tables summarising the relative palatability of different field layer and tree species. See also the field layer palatability table for a review of what is known about the palatability of selected field layer species. For more on the relative palatability of trees, see relative palatability and resilience of native tree seedlings and saplings to browsing.