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If you have walked outdoors much lately you might have seen some frothy masses of bubbles that resemble spit attached to the stems and leaves of a number of plants. In fact, the creatures that make them are called spittlebugs. Out of curiosity, I inspected a juicy wad of the foam to see what was inside.

The little nymph that was exposed was a squat little lime green bug that looked sort of like a miniature version of the 17-year cicadas we all made such a fuss about last year. The resemblance is no coincidence, since spittlebugs are the nymph stage of insects called froghoppers, which are closely related to cicadas and leafhoppers.

The nymphs suck sap from the plant, gradually enlarging and changing with each molt of the skin until they emerge as winged adults on the final molt. This sort of change is called incomplete metamorphosis, comprised of three stages; the egg, nymph and adult.

The adult froghoppers are noted for their spectacular leaping abilities, being able to outdo even the springiest of the grasshoppers. In fact, according to Malcolm Burrows of the University of Cambridge Zoology Department in England, they can accelerate with a force of up to 400 Gs. Even our best pilots and astronauts are prone to pass out at a mere 5 Gs!

Bugs gone wild

After a grueling hour in the hot humid sun last week I got a few photographs of another insect larva, this one much smaller than the monarch caterpillar. It was only a few millimeters long and was the first stage, or grub, of a beetle. But it was not just any old beetle; it was a hero.

Thousands of those Galerucella beetle larvae were being reared in special cages near the main office at the Trempealeau National Wildlife Refuge. Refuge manager Vickie Hirschboeck and refuge ranger Jenny Lilla both told me excitedly about their beetle project to control purple loosestrife that had taken over parts of the refuge.

With help from a number of other personnel plus some volunteers, they had carefully scooped up thousands of the adult beetles from a patch of purple loosestrife growing near the Winona Visitor Center. Earlier they had dug out and potted dozens of the invasive plants from the all-to-abundant supply on the Trempealeau refuge. Next, they put the potted plants into six nylon-netted cages placed in just a few inches of water. Then they carefully added the thousands of diligently plucked Galerucella beetles.

What’s the connection between the fast spreading loosestrife and the humble looking little Galurucella beetles? Well, after careful studies done at Cornell University in the 1980s, those European beetles were found to feed naturally on the purple loosestrife in its native habitat and, perhaps more importantly over here, they don’t attack any of our native plants.

Like many other European plants, the aggressive loosestrife accompanied early immigrants to America. Without natural enemies, the plant eventually spread across our continent where it has crowded out beneficial native wetland species in many places.

It thus hampers fish spawning and replaces important wildlife and waterfowl food plants. Since Cornell proved that the beetle could be introduced safely, it has been reared in insectaries like those at Trempealeau. Many government, community and private organizations thus have joined in the effort to combat the purple loosestrife.

Success has been steady, but not total. The Galerucella beetles eat out holes in the leaves of young growing loosestrife when it emerges in early summer. That’s when crews go out to infected stands to gather adult beetles and place them in the insectaries. Once there, they will immediately begin to nibble on the leaves, then mate and lay hundreds of thousands of eggs.

The larvae also nibble on the leaves for a couple weeks before descending the stems to pupate in the soil of the pots. Before they get a chance to complete their metamorphosis, the potted plants are distributed into loosestrife-plagued marshes, sort of like mini Trojan horses.

The second generation of adults will soon emerge and spread amongst the wild plants. There they feed upon on the flowers of the wild loosestrife, hindering the plant’s ability to spread and then hibernate through the winter. In spring, if all goes well, the new beetles will chew on new growth again and lay more eggs, thus continuing the cycle.

Over time, the beetles control the purple loosestrife by weakening their growth and reproductive vigor and thus their ability to overwhelm our wetlands. They are heroes! The plan is working and it’s being repeated throughout the area. The Brice Prairie Conservation Association, for instance, has a similar project on Lake Onalaska.

If you are interested in the process or would possibly like to start a project in your area, call Jessica Larson, wildlife biologist at the U.S. Fish and Wildlife Service in Onalaska at 783-4104 or call Jenny or Vickie at the Trempealeau National Wildlife Refuge at (608) 539-2311.

Monarch metamorphosis

Monarch butterfly caterpillars have been seen around the area feeding on milkweed plants lately. The females laid their eggs on the leaves so the caterpillars could snack on their favorite meal when they hatched. The young caterpillars have distinctively colorful black, white and yellow stripes around the body.

Monarch larvae grow until reaching full size of around two inches and then attach themselves to the bottom of a twig or leaf. Once attached, a miraculous process begins. They contract their bodies and surround themselves with a green, gold-spotted capsule.

Inside the capsule the pupa, called a chrysalis, remains dormant until the body has changed completely. It then emerges as an adult, gradually unfolding and stretching its beautiful butterfly wings. This is a good example of complete metamorphosis with four distinct stages; egg, larva, pupa and adult.

Whaditiz

It can produce up to 2 million seeds.

Contact Jim Solberg at (608) 782-2560 or nitefrogger@charter.net.