Objectives
- To determine the key factors influencing the success of underplanting and how will they be affected by climate change?
- To specify best practice for underplanting when using continuous cover silviculture.
Background
Transformation of forests to continuous cover management systems requires the successful establishment and growth of seedlings beneath a canopy, and their subsequent recruitment into the overstorey.
There are two main ways in which this can be achieved: natural regeneration or artificial regeneration by planting. Previously the focus of work in the project has been on natural regeneration and this has shown that for the best chances of success with natural regeneration you need:
- A good supply of seed
- A receptive seedbed for germination
- Favourable stand conditions (Hale, 2004)
- To control competitive weeds
- Little or no browsing.
Guidance on using natural regeneration in continuous cover forests can be found in (Kerr 2008).
Other work in the project has developed a simple method to assess the likelihood of natural regeneration of Sitka spruce, Scots pine, Douglas-fir and larch. The method requires visual assessment of any existing regeneration in the area (both seedlings and saplings), the percentage of the ground that is bare or covered with mosses, the amount of coning and the number of years since last thinning. Each of these five factors is scored and a total score for the forest stand is used to look up the probability of obtaining natural regeneration, i.e. is it highly likely (81-100% probability); likely (61-80%); some chance (21-40%) or poor (0-20%).
Full details of this method and how managers can apply it in the field are reported respectively in the following papers:
- Prediction of conifer natural regeneration in a ‘data-poor’ environment (PDF-2213K)
Reproduced with kind permission from the Royal Scottish Forestry Society - Natural regeneration of conifers - helping forest managers to predict success (PDF-1651K)
Reproduced with kind permission from the Royal Forestry Society
Future work will focus on artificial methods of regeneration in CCF, i.e. underplanting and this work will be carried out
in collaboration with the following research programmes:
- Seed and seedling biology
- Ecology of upland native woodlands
- Integrated forest vegetation management
Current work areas
- A comparison of the growth and survival of planted Douglas fir seedlings in restocking and underplanting situations and relationships with micro-environment conditions.
- To compare growth and survival of Sitka spruce, Norway spruce, Douglas-fir, Noble fir and European silver fir seedlings planted under a uniform shelterwood of Sitka spruce.
Main contact
Garry Kerr and Victoria Stokes
References
Hale, S.E. (2004). Managing Light to Enable Natural Regeneration in British Conifer Forests (PDF-100K). Information Note 63. Forestry Commission, Edinburgh. pp. 6.
Kerr, G. (2008) Managing Continuous Cover Forests. Forestry Commission Operational Guidance Booklet 7. Forestry Commission, Edinburgh.
