What can you expect by allowing trees to establish through natural processes?

New resource available: collection of case-studies of woodland creation through natural colonisation

By Susannah Fleiss, University of Edinburgh

How can landowners try something new, when little information is available? Stimulated by conversations among foresters, farmers, land agents and ecologists, the TreE PlaNat team have put together a number of case studies on woodland creation through natural colonisation to address this issue.

When creating woodland, land managers (such as farmers, foresters, estate owners and their land agents) usually plant trees, designing the planting scheme according to their local context, reasons for creating the woodland, planned uses, and desired species. However, allowing trees to establish through natural processes can create locally-adapted, resilient woodlands, of high biodiversity value [1]. When creating woodland through ‘natural colonisation’, seedlings germinate from local seed sources that arrive at the site naturally, some of which survive and develop into trees. A key difficulty for land managers is that the outcome of this process is not guaranteed: it is very difficult to predict the timeframe it takes to create a closed-canopy woodland, and the species which will colonise the area and survive [2,3,4].

Our project, TreE PlaNat (Treescape Expansion through Planting and Natural colonisation), is examining how, where and for whom natural colonisation might be used to create new woodlands, including in combination with tree planting. As part of this project, researchers at the University of Edinburgh are facilitating a ‘Knowledge User Board’ of land managers, who provide feedback on the research directions and findings, and help guide the project to produce useful outputs for those working on the ground. Early in the project, the group highlighted the importance of having case studies to provide land managers with examples and basic knowledge to consider using natural colonisation to create woodland. In a collaborative effort with the Knowledge User Board, we created a collection of case studies and one-page summary factsheet, available through the Edinburgh Research Archive and the TreE PlaNat website.