Com o objetivo de criar alternativas no controle químico da formiga-vermelha-de-monte, Acromyrmex heyeri (Forel, 1899) (Hymenoptera: Formicidae, Attini) foram instalados quatro ensaios com formicidas em pó, em Santa Maria, estado do Rio Grande do Sul, entre 1996 e 1998. Avaliaram-se em formigueiros médios (+/- 45cm de diâmetro) ou em formigueiros grandes (diâmetro superior a 60cm), doses de Deltametrina (2g i.a./kg), de Acefato (750g i.a./kg), de Clorpirifós (20g i.a./kg e 50g i.a./kg), de Fentiom (50g i.a./kg) e de Diazinom (10g i.a./kg). Deltametrina e Acefato, partindo-se de 5g/ninho e, Clorpirifós (50g i.a./kg) e Fentiom, partindo-se de 10g/ninho, foram eficazes no controle de formigueiros médios. Clorpirifós (50 g i.a./kg) e Diazinom, com base em 10g/ninho e, Clorpirifós (20g i.a./kg), partindo-se de 30g/ninho controlaram eficientemente os formigueiros grandes dessa espécie.
Four experiments were carried out to evaluate the efficiency of some powdered formicides on
the control of the red leaf cutting ant, Acromyrmex heyeri (Forel, 1899) (Hymenoptera: Formicidae,
Attini) in Santa Maria county from 1996 until 1998. Powdered formicides containing Deltamethrin at
2g a. i./kg, Acephate at 750g a. i./kg, Chlorpyrifos at 20g a. i./kg and 50g a. i./kg, Fenthion at 50g
a. i./kg and Diazinon at 10g a. i./kg were evaluated on middle nests (+/- 45cm of diameter) and big
nests (diameter more than 60cm). Deltamethrin and Acephate, at 5g/nest and, Chlorpyrifos (50g a.
i./kg) and Fenthion, at 10g/nest, were efficient to control middle nests. Chlorpyrifos (50g a. i./kg)
and Diazinon, at 10g/nest and, Chlorpyrifos (20g a. i./kg) at 30g/nest, were efficient to control the
big nests of this leaf cutting ant.
