Spittlebug and buffelgrass responses to summer fires in Mexico

Summer burning was used to reduce spittlebug (Aeneolamia albofasciata Lall. ) populations in buffelgrass [Cenchrus ciliaris (L.) Link] on the Carbo Liv estock Research Station in Sonora, Mexico. Five treatments included (1) an untreated control; (2) burning 7-14 days before the summer rains when the i nsect and the plant were inactive; (3) burning after the accumulation of 50 mm of summer precipitation during insect egg hatch or the second leaf stag e; (4) burning between the second and third instars or early culm elongatio n; (5) and burning between the fifth instar and adult stages or active plan t growth during the summer growing season. Summer burning after the accumul ation of 50 mm of precipitation and between the egg hatch and the third ins tars or between the second leaf stage and early culm elongation reduced spi ttlebug nymph and adult populations by 100% and appeared to stimulate buffe lgrass growth for 3 and 4 years post treatment. Burning at the peak of buff elgrass live biomass production effectively controlled spittlebug populatio ns but reduced plant production by almost 50% for 4 years post-treatment. E qually detrimental was the untreated control where nymph and adult spittleb ug populations killed more than 50% of the buffelgrass population. Summer f ires conducted after 50 mm of precipitation were easier to control than fir es conducted before the growing season when plant material was dry.