Any gifts of agricultural or business property should be specifically gifted in a Will as, if the assets fall into residue and the residue is split between non-chargeable beneficiaries (spouses/charities) and chargeable beneficiaries (most other people, including children), then a proportion of any APR/BPR may be lost.
While NRBDTs can be drafted with the intention of receiving farming assets, they are most commonly drafted with the expectation that they will receive cash or a share in the family home, meaning that farming assets fall into residue and some of the APR/BPR available is lost.
The value of farming assets may change over time, and the rate of APR and BPR available for each asset may be difficult to predict. If the clause is not drafted properly, it may mean that some of the farming business or land may fall into the trust, and some fall into residue and pass to unintended beneficiaries, splitting the business/land up.
As an example, APR is only given on the agricultural value of an asset, so if there is land which has hope value over and above the agricultural value, this land may not all go into the trust.
Serious consideration needs to be given to whether the gift into trust include cash, as well as assets qualifying for APR/BPR.
The trustees will want some liquid assets to run the trust, but the cash may be needed to equalise out gifts to, e.g. children who won't inherit the farming business.
If you gift the whole farming business into trust, including that which does not qualify for APR/BPR and exceeds any NRB, tax may be payable on the first death, which would otherwise not be payable if it passed to a spouse.
You may not want all your farming and business assets to go into the one trust, or you may only want certain parts to go into trust.