June 23, 2006
Common Milkweed, Asclepias syriaca
This native meadow plant is the sole source of food for the caterpillar of the monarch butterfly. The influx of a non-native relative of the milkweed, black swallowwort, may have a negative impact on monarch butterfly populations. Adults will lay their eggs on swallowwort vines, but the larvae are poisoned by eating them.