Japanese Beetle

 

THIS is why people don’t like Japanese beetles. This one is “skeletonizing” a leaf on my grapevine, that is, eating the soft parts between the veins and leaving behind a big lacy hole. They do this to a wide variety of plants that range from linden trees to roses. Click here for the USDA’s National Invasive Species Information Center’s entry about them.      Click the photo to enlarge.

Adult Japanese beetles are easy to recognize. They are shiny metallic green scarabs about one-half inch long with bronze-colored wings. Five pairs of white hair tufts project from under the wing covers on each side of the body and another pair decorate the rear end of the abdomen. Kind of pretty.

Just get off my grapevine, eh? And stop looking at the linden tree.

On the Grapevine

 

Behold my concord grapevine in its summer glory. When I planted it last year it was a leafless and unpromising looking stick. This year it reached the top of its trellis. 

And it's making grapes for the first time!

And word apparently got out to the insect community about it. This appeared. It's a native North American insect that's commonly called a grapevine beetle. Although grape leaves are its main food, it's not considered very damaging.

It has that classic scarab beetle look.

As does the Japanese beetle, famous for eating everything, including grapevines, and is a well-known plant destroyer.

Here's a gang of Japanese beetles having a party on what's left of a hibiscus flower. They remind me of orcs. Note the couple copulating in the lower center of the shot.

Last and worst, there are lanternflies, a newly introduced insect problem. There are a lot of them trying to eat our grapevine. We're controlling them with handheld spray bottles of insecticidal soap.

 

All four nymphal stages showed up on the grapevine in successive waves and now lots of adults like the one pictured here. 

Nevertheless, I am looking forward to reporting about homemade grape jelly in September.

Summer Garden

 

This is a good time of year to take a walk in a community garden. The zinnias are lovely around here right now. Click to enlarge.

You might see cantaloupes growing on the vine, not like we usually see them in the supermarket.

Or pretty grapes on a weathered wood fence.

Or trendy veggies like this Tuscan kale. It's called dinosaur kale, too, for its presumed resemblance to bumpy dinosaur skin.

Sometimes there are interesting insets to see like this harlequin bug. 

Here's a closer look. The name harlequin comes from a character in 16th century Italian comedy who always wore a multicolored costume. Apt, except that this colorful bug is no joke in the garden where it can be very destructive. 

 

Harlequin bugs were having a big party on the kale the day I was there.

And look at all the Japanese beetles on this zinnia flower! 

Yet the gardeners seemed to be holding there own against the insets, producing an abundance of lovely summer plants. Good job, gardeners.

Time to Smell the Roses

Brooklyn smells like roses this week. 

Well, maybe not everywhere -- but the parks smell great. I was home for a week-long stay-cation and I took a walk in nearby Brooklyn Bridge Park every day. The air was sweet with the scent of roses and I recommend a visit while they are still in bloom. And when you pause to smell them, take a look inside.

You might find a rose weevil, making holes.

Or a lovely half-green sweat bee.

Or maybe a honeybee with its pollen sacs full of yellow rose pollen. 

Or a Japanese beetle. Click on the photos to enlarge. 

Or even a pair of common eastern bumblebees double-teaming. 

There's lots more going on in there. Take a look. And a sniff. 

Bee meets Beetle

A Japanese beetle and a brown-belted bumblebee on milkweed flowers. The bee is touching the beetle with a foot; they both drew back a second later. Click to enlarge.

"Summer afternoon -- summer afternoon; 

to me those have always been 

the two most beautiful words in the English language." 

Henry James

The Japanese beetle and the blue-winged wasp

The rose borders around the amphitheater in Brooklyn Bridge Park are relatively new -- I think they were planted last summer. But already Japanese beetles are abundant there. Japanese beetles love to eat roses. And after a meal of petals they meet and mate.

A Japanese beetle couple in the Brooklyn Bridge Park roses. 

Adult Japanese beetles are shiny metallic green, oval, convex, and about one-half inch long with bronze-colored wings. Five pairs of white hair tufts project from under the wing covers on each side of the body and another pair decorate the rear end of the abdomen.

The Japanese beetle, Popillia japonica. Pretty! 

The first report of Japanese beetles in the United States was from a plant nursery in New Jersey in 1916. The insects quickly spread to the wild and we have been trying to eradicate them ever since. Adult Japanese beetles eat flowers, vegetable crops, fruit trees, and ornamental plants. They are famous for eating the soft flesh of leaves from between the veins and leaving behind leaf skeletons. They eat soft rose petals completely. As if that were not bad enough, the larval stage lives in the soil and eats grass roots, damaging lawns. A Japanese beetle larva is a white worm-like "grub" that is about an inch long at maturity; it has three pairs of tiny legs and a round brown head.

After mating, a female Japanese beetle lays eggs in the soil. She lands on the ground and digs a burrow a few inches deep. She lays a few eggs and then she feeds and lays intermittently until she has ensconced a few dozen eggs in the soil. The eggs hatch into larvae by midsummer. The larvae burrow around underground, eating grass roots. When cold weather comes the larvae dig deep in the soil to spend the winter inactive far below the surface. In spring they burrow back up to root level and eat and eat and eat. After a brief pupal stage they emerge as adults and dig themselves out of the ground.

The Japanese beetle life cycle takes a year. Ten months of that are spent underground. Summer is their time to shine; they have just two adult summer months to fly in the sunlight and eat roses.

But Japanese beetles are not the only insects that have moved into the new park. I found the blue-winged wasp pictured below sipping nectar from goldenrod flowers in the park's water garden. The blue-winged wasp in about an inch long. Its head, antennae, and legs are black. Most of its abdomen is reddish brown. Two bright yellow spots on the upper surface of the abdomen make it easy to identify.

The blue-winged wasp, Scolia dubia. 

Female blue-winged wasps take breaks from sipping nectar to fly low over grass. They search for beetle grubs. They love Japanese beetles. The wasp burrows into the soil to find them. (Not surprisingly, they are sometimes called digger wasps.) The wasp will sting a captured grub to paralyze it. Then she digs deeper, constructs a little cell, lays an egg right on the unlucky grub, and departs. When the wasp egg hatches into a larva it will feast on the beetle grub its mother left for it. The wasp larva grows, eating grub, and eventually makes a cocoon right inside the grub's corpse where it spends the winter. Ghoulish, eh? The new wasp emerges as an adult in spring or summer, just about when the Japanese beetle grubs are beginning to fatten up.

This is almost enough to make me stop complaining about mosquito bites -- obviously some species have much bigger insect problems!

Blue iridescent reflections give the blue-winged wasp its common name.