Milkweed Menagerie at Rutgers Gardens

When I see a stand of milkweed plants, I always stop to see what insects might be using them. When I stopped at a group of Common Milkweed plants (Asclepias syriaca) at Rutgers Gardens, I found the first Monarch butterflies (Danaus plexippus) that I have seen this summer. I only saw a couple adults, but I expect there will be more soon. Monarch caterpillars are among the few insects able to eat the leaves of milkweed plants; the toxins in the leaves makes the adults distasteful and gives them their bright orange color.

In addition to the Monarchs, I saw another expected species, the Red Milkweed Beetles (Tetraopes tetrophthalmus). I have written about these in previous posts. As with Monarchs, the bright red coloration advertises the beetles' distastefulness to potential predators. Sharing space on the flower cluster with the beetles were Ailanthus Webworm Moths (Atteva punctella), the narrow orange and white insects in the photos above and below. These may look like caterpillars, but they are adults, and the adults often nectar at flowers. Its caterpillars feed mainly on tree-of-heaven (Ailanthus altissima), an invasive species, but the moth itself is native. They must have fed on some other plant prior to the introduction of Ailanthus.

On the same clump of flowers there was one other insect that initially evaded my attention. However, my camera did catch it, and it is in the photo above. (If you cannot find it, click through and look for the note.) I think this is a Tarnished Plant Bug (Lygus lineolaris), a very common true bug. These feed on the leaves and flowers of many plant varieties.