Revegetation is the establishment of local native plants to create plant communities using one of several methods.
Usually, this is undertaken to extend or provide shelter for an existing forest area.
It is also possible to recreate forest areas through a carefully planned revegetation programme.
There are many examples of stable and self-sustaining forest areas around New Zealand that 20-30 years ago were areas of grass or herbaceous and woody weeds.
A revegetation project will normally span many years, so careful planning is essential to ensure that all matters have been thought through so that the project will succeed.
Many revegetation projects falter after considerable time and resources are put into them because an important aspect is overlooked or because resources are not budgeted for more than one or two years.
For example, if weeds are a serious problem, they should be controlled or eradicated before any planting takes place.
Plants need to be ordered or propagated 18 to 24 months before planting so they are of an appropriate size for planting out (30 to 60cms).
It is important to itemise the level of resources and the time that will be required each year for the duration of the programme. The costs and time can then be anticipated and budgeted for.
It is a good idea also to plan the year ahead and highlight necessary actions in a 12 month plan. For instance, controlling rabbits and hares at a planting site needs to be undertaken well in advance of planting.
Figure 1 illustrates the range of options and stages that need to be considered and planned for in a revegetation programme.
The importance of recording as much information as possible about all aspects of a revegetation programme cannot be over-emphasised.
Not only will this information assist in an assessment of the present methods (what has worked and what has not) but also it will assist others who may embark on a similar programme.
If possible, record:
In many cases a revegetation project will be extending an existing forest area or restoring gaps (‘light wells’) within an area.
Where these areas are small, the choice of site does not need further consideration.
In larger areas, there will be various sites and some parts will be more suitable for the establishment of plants than others.
The more favourable microsites should be used first to establish plants. Features such as remnant patches of top soil, or moist depressions that are sheltered or frost free, contribute to rapid plant growth.
Planting on favourable microsites first helps to create a more favourable environment for subsequent plantings.
Take time to observe nearby sites where native plants are growing naturally. Nature will have done the hard work of matching the right plants to those particular sites.
It is then quite a simple matter to repeat those vegetation patterns on the proposed revegetation site.
The other possible type of site for a revegetation project is a bare site covered only in grass or weeds. The site should be assessed for areas where plant establishment is likely to be optimised, and these areas used first.
When starting a revegetation project and you have the choice, do not choose sites that are very exposed to prevailing winds, subject to water logging in winter, or are ‘frost-pockets’ where cold air produces heavy persistent frosts.
If in doubt, seek local advice from nearby landowners if they are more familiar with the area.
If possible, choose sites that are well sheltered, have adequate moisture and fertility, and have no problem weeds.
It is possible to revegetate the most difficult of sites with native plants. It is just a matter of matching the right plants for the site and the right revegetation method.
Open SpaceTM Magazine No. 37, September 1996 © QEII National Trust