Population assessment methods for Heterodera schachtü were compared in two tests. In the first there were no consistent differences between numbers of H. schachrü extracted by Fenwick cans (at two laboratories), a flotation column and an automatic cyst extraction apparatus, from dried soils from three sites containing no other cyst nematodes. The second, made on 54 commercial sugar beet fields, compared numbers of H. schachtü extracted from dried soil samples by Fenwick cans (at two laboratories) with results of a bioassay of soil samples and a subsequent examination of roots in the field. Most samples were placed into the same broad groups by the cyst extraction and bioassay methods and the two techniques were equally good at predicting field infestations.