a1 A.R.C. Unit of Statistics, University of Edinburgh
a2 C.S.I.R.O. Division of Mathematics and Statistics, Canberra
In this paper we present a series of resolvable incomplete block designs suitable for variety trials with any number of varieties v in the range 20 ≤v ≤ 100. These designs usefully supplement existing square and rectangular lattices. They are not necessarily optimal in the sense of having smallest possible variances but their efficiencies are known to be high.
(Received September 19 1977)