Let T be a spectral
operator on a Banach space, such that its resolvent satisfies a m-th order
rate of growth condition. If N be the nilpotent part of T, it is known that
Nm= 0 on Hilbert space. We show that Nm= 0 on an Lp space (1 < p < ∞).
Known examples show that Nm need not be zero even on an uniformly convex
space.