What is 'Natural Regeneration'?

At it's simplest, Natural Regeneration is nature doing it's own thing without human intervention. It usually refers to the idea of process by which native species return to areas of land that have been degraded (usually by the activities of humans). Natural regeneration should occur as long as there is sufficient existing native biodiversity in the area. It may take time but regeneration should occur. Those species that are most suited for the particular habitat at any time will take do best. As time passes, the habitat will change and other species may take the place of the earlier pioneers.

Why use Natural Regeneration?

Those practising conservation woodland management generally consider Natural Regeneration to be preferable to artificial methods in most situations. Even commercial forestry operations may use of natural regeneration. There are both advantages and disadvantages to using natural regeneration.

Some of the advantages include: good early root development by native seedlings, less disturbance to soil ecology and reduced risk of soil erosion, low cost establishment, less labour and equipment required, no problem with geographical origin of seed, and less visual impact compared to clearcuts/plantations.

The disadvantages are mainly of economic concern and include: less control over initial stocking and spacing, generally lower commercial yields, no genetic 'improvement' or the introduction of disease resistant stock, possible delays in regeneration due to drought or inadequate seed fall and the possible need for precommercial thinning to ensure good growth.

Threats to Natural Regeneration

Unfortunately there are places where loss of biodiversity or the introduction of invasive non-native species have upset the balance of nature. At Steward Wood for example, native species such as oak would eventually, given the chance, recolonise and produce a woodland characteristic of the semi-natural native woodlands traditionally found in the area. However there is lots of sycamore growing in Steward Wood which is a very invasive tree that competes with the native trees.

It is grazing animals that represent the biggest factor preventing natural regeneration. Livestock such as Sheep, will eat any unprotected saplings they find growing in a field. Rabbits also enjoy nibbling on the tender leaves of young saplings. In a woodland it is more likely to be deer that munch away the new shoots. Clearly natural regeneration may sometimes require little help and encouragement.

Encouraging Natural Regeneration

It seems almost a contradiction in terms but human assistance in the process of natural regeneration may be necessary in some situations. Disturbances to the natural environment caused by human activities have in many cases made conditions unfavourable so Natural Regeneration and so active steps may be required to tip the balance back in favour of the native species.

For us at Steward Wood, the steps taken to encourage natural regeneration are mainly those attempts to control the invasive species that compete with the native trees that are trying to regenerate. For example, clearing areas of sycamore away from self seeded oak saplings and thinning out the conifers to open the canopy. We also endeavour to locate individual native saplings and fitting tree guards to protect them from damage caused by deer, as well as adding mulch to reduce competition from ground cover plants.

The role of seeding and tree planting

Steward Wood has many large maiden trees providing seed to restock the woodland with native varieties. These trees mainly occupy the boundaries of the land. Given time their seeds will find their way, with the help of birds and rodents etc., all around the woodland. Given the chance, a significant number would grow and restore the woodland to it's traditional glory.

Sometimes, in order to assist and speed up the natural process, people may collect and scatter seeds themselves, or perhaps raise seedlings and planting them out. This method may be particularly useful where a group fell of non-native species has occurred some distance from any examples of native species. We prefer the idea of letting nature choose where the trees will grow but we may find it appropriate to plant some trees when natural regeneration seems less viable.