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Several Opuntia spp. and Nopalea cochenillifera (Cactaceae) are used in semi-arid regions of North-East Brazil as fodder for cattle. The possibility of using biological and other alternative methods to control pest populations of scales, Diaspis echinocacti, which is an important pest of these cacti, could reduce the use of toxic insecticides that are harmful to humans and animals. To this end the use of entomopathogens (Beauveria bassiana and Metarhizium anisopliae at 10(7) and 10(8) conidia ml(-1)), a 3% hexane fraction of neem seeds and a mixture of soap, tobacco, kerosene and water were evaluated for the control this pest. The neem seed extract gave the highest mortality while M. anisopliae (10(7) conidia ml(-1)) was the least effective. The use of biopesticides and biological control provided acceptable levels of control of D. echinocacti and could be an alternative approach to the control of this pest on fodder cacti in Brazil.