Forest Entomology

A special branch of agricultural entomology deals with forest pests (Dourojeanni Ricordi 1963, Gray 1972). The tremendous value of wood products makes this one of the most important fields economically but one somewhat neglected in Latin America. For this reason and because there are a large number of commercial timber species and forest types, it is difficult to generalize about forest pests in this part of the world. Only a few area studies or surveys have been conducted (Martorell 1945). Investigations on eucalyptus, snapdragon tree (Gmelina arborea), and pine (Pinus caribea) pests may become more appropriate as these exotic timber types replace native Neotropical hardwood species.

There has been a tendency to regard insect communities in mixed tropical forests as relatively stable, that is, subject to only small population fluctuations, compared to temperate forests. Thus, the likelihood of severe outbreaks are thought to be remote. However, as various authors have reported a number of localized population explosions in Old World tropical forests similar to those encountered in temperate regions, the possibility remains for similar occurrences in Neotropical forests.

Wood-boring beetles are the most common and serious timber pests. Their larvae molest all parts of the young, mature, and harvested tree. Most belong to the families Cerambycidae, Scolytidae, Curculionidae, Platypodidae, and Buprestidae. Damage to standing timber is almost wholly due to termites of the family Termitidae, in particular, members of the genus Coptotermes (Harris 1966). In their resin-gathering activities, stingless bees may damage nursery seedlings by boring into and gouging the stems of new plantings (Gara 1970).

Many lepidopterous species are no doubt injurious to timber trees in Latin America as they are to those of temperate forests, but little is known of the economic impact of the numerous leaf-feeding and wood-boring types. The mahogany web-worm (Macolla thyrsisalis, Pyralidae) is one recognized pest species of mahogany (Howard and Solis, 1989).

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