Triacontanol, tricin and tetramethyl-N,N-bis(2,6-dimethylphenyl)cobutane-1,3-diimine, newly reported from Arundo donax, showed significant antifeedant activity against the boll weevil, Anthomus grandis. A common mixture of phytosterols was also obtained from the aerial parts of the plant, but none showed any antifeedant activity.