A non-descriptor referring to two Descriptors

Not allowed? But I felt its need while revising/refining terms under
Alternative agriculture.
Biological farming includes:
* organic farming
* biodynamic farming
Making `Biological farming' a Descriptor is still undecided. In case it is left as a Non-descriptor, I would like to make it a broader synonym of `organic farming' as well as `biodynamic farming'.

Now my dilemma is:

(1) Should `biological farming' be made a Descriptor and NT under alternative agriculture? Should `organic farming' and `biodynamic farming' become NTs under `biological farming'?
(2) Should `biological farming' be left as a Non-descriptor and refine it as a `nearSynonym' for `alternative agriculture'? (or) Can I make it a `broaderSynonym' for both `organic farming' and `biodynamic farming'?



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