Interestingly, page 2 of the UPM Tilhill download states:
No income tax relief is available for the cost of assets used in forestry, nor any woodland expenditure, nor interest on loans for the purchase and or management of woodlands.
This is exactly an area I was interested in.
I've been employed on PAYE and simultaneously self-employed in an unrelated area to my main job in the past, and keeping things absolutely and demonstrably straight with book-keeping (especially on areas of overlap / dual use), stopped a potential query by HMRC in its tracks (and in a round about way confirmed a malicious source to the origins of their query (but that's messy divorces for you...)
More positively, present activities potentially see a significant expansion from not quite commercial orchard and conservation area, to woodland activities bordering on small-scale forestry (resulting in processed and unprocessed products) - and with a low impact non-forestry aspect on the plot that may give an income. (There may still be an unrelated PAYE aspect for a while too).
It's the overlap ofexpense activities with similar tools and equipment for management that might grey things if looked at from the wrong angle.
However, not declaring the expenditure and income isn't a long-term solution.
(I feel cheeky enough to put tuition fees for an ecology college course down as legitimate expense though)...
In some ways I'm fortunate that capital expenditure items like plant, machinery and larger tools already overlap (and exist) as part of my meadow conservation and orchard activities without having to acquire much.