Have You Seen This Beetle?

Posted on August 5, 2013 by Rosemary

Asian long-horned beetleThere’s a dangerous insect on the loose. Shiny black with bright white spots, the non-native Asian longhorned beetle (or ALB for short) feeds on a wide range of trees to the point of destruction. Once infected, a tree can’t be saved; tens of thousands of trees have already been lost in the northern and central US.

Now is the time to stop the ALB in its tracks. The insect is most active in August, which has prompted the USDA to launch Tree Check Month. Early detection is critical as the beetles can do immense damage in a short period of time.

Ready to pitch in? Here’s what you need to know.

About ALBs
Native to China, Japan, and Korea, the Asian long-horned beetle was first detected in North America in 1996. Most likely it hitchhiked aboard wooden packing material. Since then, it has destroyed over 80,000 trees in Massachusetts, New York, New Jersey, Ohio, and Illinois. Back in 2008, 27,000 infested trees had to be removed in Worcester alone.

The ALB infests hardwood trees, such as maple, birch, horse chestnut, poplar, willow, elm, and ash. The beetle’s larvae burrow so deeply into the tree that insecticide won’t reach them, and it’s impossible to extract them. In the past, they have been reported in Greater Worcester and there was a small infestation in Boston.

Check your Trees
Fortunately, we can fight back. Eradication efforts have already banished the beetle from Illinois and New Jersey, and parts of New York are expected to follow soon.

The most important thing you can do is to check your trees for infestations. Here’s what to look for:

  • Small, perfectly round dime-sized holes (3/8″ up to 1/2″ in diameter) with smooth edges, left by adult beetles exiting a tree.
  • Shallow oval scars in the bark (1/2″-3/4″ wide) where the eggs are deposited.
  • Sawdust-like material on the ground and in branches, pushed out by the larvae as they burrow.
  • The beetle itself. Mature ALBs measure 1 to 1.5 inches, with two antennae (the “horns”) that can grow up to 4 inches long.

The USDA’s Asian longhorned beetle site features a slideshow of images (including ALB look-a-likes) and includes a tool to report sightings.

The Secret Life of a Giant Silk Moth

Posted on July 31, 2013 by Kristin S.

Cecropia MothIf you’re under the impression that moths are dull creatures who eat holes in sweaters, you haven’t encountered a giant silk moth. Luna moths, Promethea moths, Polyphemous moths, and Cecropia moths are all native silk moths of the subfamily Saturniinae.

These amazingly large, stunningly beautiful moths are found throughout Massachusetts, but we rarely see them. Flying mostly at night and spending much of their lives as caterpillars and cocoons, these moths fly under the radar. Observing one in action is always a WOW experience.

Life Cycle of The Cecropia Moth

In late May and early June, adult Cecropia moths (pictured above) emerge from their cocoons. With a wingspan of 5 to 6 inches, the Cecropia moth is the largest moth in North America. Adults are born without mouth parts, do not feed, and have one job: to mate and reproduce. Males have large feathery antenna, which can pick up the scent of a female from a mile away.

After mating, females lay more than a hundred eggs, usually in small rows on the underside of leaves. Around 10 to 14 days later, tiny black caterpillars emerge. The caterpillars are eating machines and feed on the leaves of many common trees including cherry (a favorite), sassafras, lilac, ash, apple, poplar, and willow.

Cecropia Eggs

The caterpillars go through 5 instars (i.e., skin sheddings), and grow very large. By the 5th instar they’re often at least 4 inches long and thicker than an adult thumb. They are also remarkable looking, with a frosted green coloring and red, blue, and yellow knobs extending from their bodies. Children often remark that it looks like ladybugs are riding on the caterpillar’s heads!

Cecropia Caterpillars - Cara Yacino

The caterpillars have many enemies and mortality rates are high. After weeks of eating and growing, the rare caterpillar that has successfully reached the 5th instar is ready to cocoon. On a branch or twig, the caterpillar will spin a rough, brown, spindle-shaped cocoon. The caterpillar will spend the winter in the cocoon, transforming into an adult moth, ready to emerge in late spring.

Cecropia Moth Cocoons

Status of Cecropias

Sadly, Cecropia moth numbers appear to be in decline due to habitat loss, pesticide use, and parasitism by a tachinid fly introduced to control the Gypsy Moth. (See Boettner et al, 2000). Maintaining a pesticide-free yard full of native plants and natural spaces is one way to help these amazing creatures. Some people go a step further and raise silk moths to increase their numbers, a labor-intensive and rewarding experience.

Learn More

Join a mothing or insect program at a Mass Audubon wildlife sanctuary near you.