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Restoring native fungi back into revegetation and degraded woodlands Healthy natural woodlands throughout Australia have a greater diversity of native fungi than degraded woodlands or revegetated agricultural lands. For example three years of surveying in woodlands near Kellerberrin in Western Australia have shown only 10 native fungi occurring in revegetation compared to more than 100 fungi in nearby woodland remnants. No native fungi were observed in cleared crop lands. (For further details see the book chapter by Tommerup & Bougher (2000).)
Native fungi can be helped back into revegetation or degraded woodlands using simple, low cost methods that are not disruptive to the environment, and are compatible with revegetation techniques currently in use. All it takes is a willingness to incorporate fungi in revegetation programs, and a degree of confidence about what you are doing.
Currently there are no commercially available sources of native woodland fungi to apply to native plants for revegetation on wheatbelt farms. Appropriate fungi need to be chosen from remnant woodlands, such as local fungi suited to local conditions and former natural vegetation type (see Choosing native fungi). Spores of decomposer fungi can be applied to any plants. However, effort will be wasted if you apply spores of a mycorrhizal fungus to plants which are not compatible with mycorrhizas. Some notable examples of non-mycorrhizal plants include the banksias and dryandras. (See also the CSIRO Mycorrhiza website for more detail about Australian mycorrhiza and Using VA mycorrhizal fungi.)
Fungi can be put directly into revegetation sites before or after the plants. However this is likely to be less successful than raising plants already growing with fungi before they are planted into revegetation areas. There are a variety of methods currently being tested to produce plants already growing with fungi. The recommended methods below (for Mushrooms and Puffballs & Truffles) have been tested and have successfully introduced native fungi into revegetation trials on Australian farms.
Why are the fungi so different in woodlands and farms? Fungi in woodland soils are very different to those in agricultural soils. Factors that affect fungi and help explain why there are big differences between the fungi in woodlands and farmlands include:
When woody plants are revegetated on former farmland, most native fungi are unable to colonize and thrive in such an alien soil environment. Practically all native fungi which are the symbiotic partners of woodland trees and shrubs are destroyed in agricultural fields. Most do not re-establish even in 20 year old revegetation.
Just as we put back plants, we also need to help put back the original fungi into revegetation.
Why? Many hundreds of native fungi have long helped maintain the health of woodlands, e.g. by building organic matter, sustaining soil nutrient cycling processes, soil fertility, and directly assisting better plant growth of native trees like eucalypts and sheoaks.
Native fungi are not self re-establishing in woodland revegetation on farmland. Only a very low proportion re-establish in revegetation on badly degraded land or cultivated land at least in the short to medium term. The fungi need help to be re-introduced from Australia’s native remnant woodlands into revegetation.
When we put the trees and shrubs back we should also be putting the fungi back to help re-establish diverse soil biodiversity and to kick-start healthy soil processes. This can help support long-term health of the plants, and additionally this simultaneously contributes to biodiversity conservation below-ground as well as above-ground.
Race against time
Currently there are no commercially available mixes of native woodland fungi to apply to native plants for revegetation on wheatbelt farms. Therefore remnant woodlands are the only source.
Goals of efforts to restore Before considering obtaining native fungi from natural woodlands and trying to help them get into revegetation and degraded woodlands, it may be timely to define the goals of undertaking such effort. To help determine goals, three major points need to be recognized: 1.
2.
3.
How many fungi to help get back It is not realistic to attempt re-introduction of all native fungi that occur in Australian natural woodlands of local or regional areas - not even all of the larger fungi. However if at least some fungi are assisted to return this may encourage others to self-follow later as the environmental conditions in revegetation become more similar to those of woodlands. Hence there should be no set target for how many, and which, fungal species will be needed in different regions. If broad targets are needed, knowledge of fungi enabling estimation of fungal diversity in local woodlands and revegetation would help to decide targets.
An arbitrary scale of desirable improvement can be visualised as below.
Print Friendly Version (Section: "Using for Revegetation")
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As a parallel matter of urgency, native fungi also need nurturing in natural woodlands and poor quality native vegetation remnants too, as these are
The benefits are primarily for long-term sustainability of biodiverse, self-sustaining revegetation and woodlands, not for short-term gain - such as expectations of faster growing trees.
There are not likely to be obvious signs or differences in revegetation with or without native fungi. This is because the presence of fungi is not easily measured as they are out of sight except when they fruit, and the jobs they do which contribute to landscape health occur mainly out of sight.
It is unrealistic to expect to be able to help all of the fungi present in local remnant woodlands to return into revegetation on farmland. A more practical goal is to target helping some fungi to return, and to encourage others to self-follow later by retaining and nurturing remnant woodland nearby. 
