Here is the detail from the Domestic RHI Consultation outcome policy document. I have removed all the links:
"88.
To be eligible for and continue to receive RHI support for a biomass system, fuel needs to be sourced from a supplier registered on an approved supplier list. Such a list will be set up ahead of the launch of the scheme and will be the same one that is being established for the non-domestic RHI scheme.
89.
RHI recipients will have to make an annual declaration that they are using only approved fuel from an approved supplier, and keep receipts as evidence for future audits.
90.
To be included on the list, we intend that fuel suppliers will have to meet two criteria from April 2014:
i. Supply fuel which complies with the greenhouse gas (GHG) lifecycle emissions target of achieving 60% GHG savings against the EU fossil fuel heat average, assuming a boiler efficiency of 70%
ii. Report their performance against the relevant land criteria from the following list (although compliance with the criteria will not initially be required):
a. For wood - fuel: the UK public procurement policy on wood and wood products, or its equivalent.
b. For perennial energy crops planted under the Energy Crops Scheme for England, or its equivalent: the sustainability requirements set by that scheme or its equivalent. This scheme may be coming to a close, so we may need to revisit this area to ensure there is no gap in sustainability requirements. In doing so, we will seek to take an approach that is consistent with the non-domestic RHI scheme.
c. For other types of solid biomass: the sustainability criteria set under the Renewable Energy Directive.
In line with the non-domestic RHI scheme, our intention is to make compliance with the land criteria mandatory from April 2015, subject to EU and international legislation.
91.
Further information about the criteria can be found in the Government Response to the July 2012 non-domestic RHI scheme consultation entitled ‘Providing Certainty, improving performance’.
92.
Work is ongoing to develop an approved supplier list and we expect it to be in place before the launch of the domestic RHI scheme. Further details will be published closer to the launch of the scheme. With a view to minimising administrative burdens, we intend that woody biomass feedstocks (which includes perennial energy crops as well as wood) grown on the same estate as an eligible biomass system will be automatically treated as meeting the sustainability criteria provided they do not also supply to other biomass heat installations. Our aim is that people in this situation register their details as a self-supplier and provide accompanying evidence. We will also look at introducing a proportionate approach for suppliers who only supply to their local area (local suppliers)."
So you can see foraging etc appears not to be covered. If you are coppicing your own land, you should be OK. The word estate jars a bit. Sounds as if you get your wife or servant to do all this.......
For most it will be a registered supplier. Hopefully the proportionate approach will be proportionate (but in whose eyes?) If there is too much paperwork or cost, small guys won't bother. We will have to await the detail in the autumn.