If I understand it correctly, you can just look it up.
Woodland Trust:
> In England, planning permission isn’t needed if your project is under 2ha and in a low risk area. Check your area using the Forestry Commission land information search.
Then enable the Forestry Commission > Targeting and Scoring > Low Risk Areas for Woodland Creation layer.
At the very least, if your plan is to just beg forgiveness, it would give you a better argument that you thought it was acceptable and at least tried to comply.
How do you expect one determines an area to be low-risk? To do so requires assessment from all stakeholders who could deem it not to be low-risk.