Published online by Cambridge University Press: 10 July 2009
An experiment was carried out in 1968 in the Lossitete Forest area of northern Tanzania to compare the fly-round and the Langridge-trap as sampling techniques for assessing the effectiveness of 0·4% pyrethrum applications on Glossina pallidipes Aust. when applied from the air. From fly-rounds, population reductions of 64%, 36% and 29% after the first, second and third applications, respectively, were estimated, whereas from Langridge traps the reductions were 11%, 7% and nil, respectively. Taking into consideration the efficiency of the Langridge-trap and the limitations of the fly-round in sampling G. pallidipes populations, it is concluded that the fly-round may give a false assessment of reduction of G. pallidipes after insecticide application.