Saturday, May 19, 2009
Ecologist John Lill led a group of 15 adults and children on our second Caterpillar Hunt, this one in the Kemp Mill area just below Colt Terrace. He pointed out that caterpillars are among the fastest-growing organisms in nature, increasing in mass 1,000-fold as they mature from egg to larva. He noted that locally, black cherry and oaks are particularly rich in caterpillar variety, tulip tree less so, with maples hosting somewhat fewer still. The cherry hosts many species even though the leaves produce a form of cyanide that is activated upon chewing. Tent caterpillars, among others, have evolved a metabolism that counteracts the poison. John is an insect-plant ecologist at George Washington University, specializing in forest caterpillars.