  We study the problem of decoupling of heavy chiral superfields in
four-dimensional $N=1$ supersymmetric field theories with Lorentz-invariant and
Lorentz-violating higher-derivative terms. We demonstrate that the earlier
found effect of large logarithmic quantum corrections, due to heavy chiral
superfields, takes place not only if the theory possesses quantum divergences,
but also for essentially finite theories involving higher derivative terms,
both Lorentz-invariant and Lorentz-breaking ones.
