There is in fact one other requirement: Patience. We have just measured one, it fits the required criteria in length and diameter. So far, so good. The first oaks measure around one meter (3.2 feet) in diameter. ($1 = 0.8432 euros)
There is in fact two other requirements.
( z0 require :quant 2 :mod ( z1 other ) :mod ( z2 in-fact ) )
(z0 / require-01
    :quant 2
    :mod (z1 / other)
    :mod (z2 / in-fact))
There is in fact two other requirements .
z0 :mod z1
z0 :quant 0
z0 :mod z2