A photographic method and a ranking procedure for estimating numbers of the rose aphid,Macrosiphum rosae (L.), on rose buds

Two sampling methods for aphids are described. The first is a photographic method that allows sampling with replacement for use in field experiments and in which a linear regression technique is used to estimate the errors of sampling. The second method is a ranking procedure for sampling natural populations in which regressions of aphid numbers on ‘colony length’ are used to minimize bias.