Sunday, August 05, 2012

Goldenrod


Weather: Rain; 35:57 hours of daylight today.

What’s blooming in the area: Hybrid perpetual roses, buddleia, bird of Paradise, silver lace vine, trumpet creeper, red yucca, rose of Sharon, hibiscus, datura, sweet pea, alfalfa, Russian sage, purple garden phlox, single sunflowers, yellow flowered yarrow, zinnias, Shasta daisies.

Apples so laden branches bending; fruit beginning to drop.

Beyond the walls and fences: Leatherleaf globemallow, bush morning glory, white and pink bindweeds, white sweet and white prairie clovers, silver leaf nightshade, buffalo gourd, knotted spurge, prostrate knotweed, goat’s head, pale blue trumpets, Hopi tea, gum weed, goat’s beard, horseweed, wild lettuce, golden hairy asters, goldenrod.

In my yard, looking east: Bouncing Bess, Jupiter’s beard, hollyhock, winecup mallow, sidalcea Party Girl, California and Shirley poppies.

Looking south: Rugosa, floribunda and miniature roses, Dutch clover, Illinois bundle flower, scarlet flax, Sensation cosmos.

Looking west: Caryopteris, Siberian and Seven Hills Giant catmints, calamintha, leadplant, David phlox, white spurge, perennial four o’clock, sea lavender, Mönch asters, purple coneflowers.

Peach bough that normally reaches down to my forehead, is now shoulder high with fruit.

Looking north: Hartweig evening primrose, nasturtium, chocolate flower, coreopsis, blanket flower, black-eyed Susan, Mexican hat, chrysanthemum, yellow cosmos.

Bedding plants: Petunia, nicotiana, snapdragons, sweet alyssum.

What’s blooming inside: Zonal geraniums, aptenia.

Animal sightings: Rabbit, hummingbirds, small brown birds, geckos, butterflies, bees, hornets, harvester and small black ants.


Weekly update: Goldenrod has gone from being a sentimental favorite to an enemy through no real fault of its own. It’s simply too successful at being a member of the composite family.

The problem isn’t that the roots are too aggressive, which they are in areas where they survive; my yard isn’t one of those places, but the ditch banks around the village are.

The problem isn’t that it produces too much pollen. This isn’t a tale of a late allergic reaction. Besides, I believe the people who say it’s the late summer blooming, inconspicuous ragweed that’s the instigator of hay fever.

The problem is that its nectar is too alluring. If you ever try to get near a patch, you’ll keep your distance. Bees and hornets swarm around it. I’ve also see large flies, things too tiny to identify and some rather large insects with some red parts.


But they aren’t my enemy. It’s the locust borer, Megacyllene robiniae, a creature with red legs that tries to pass as a hornet. Its dark brown back has yellow strips that are horizontal on the upper part of the body and chevroned on the longer lower section.

The locust borer feeds exclusively on the nectar of goldenrod, then lays its eggs in fissures in the bark of a black locust tree. The young hatch within two weeks and bore into the bark where they go dormant for the winter.

When weather warms in the spring, the larvae resume boring into the trees, reaching the heartwood and leaving a trail of sap and sawdust. They pupate in mid-summer and emerge as adults in August when goldenrod is blooming.


When I first saw a pile of sawdust a few years ago, I called a tree specialist who told me there was little I could do. He said that people who grow commercial stands, harvest the trees which come back from their roots. The locust, Robinia pseudoacacia, is a legume.

He didn’t want the job of cutting down my tree, but sent one of his laborers to do it as a side job. The problem is they left me with the dead, insect infested trunk. I’ve been through the cycle four times now, and my biggest problem has been getting someone to understand the key to breaking the cycle is to remove the diseased wood before the adults emerge.

He took the presence of the insects as fate. There’s no truly effective chemical on the market. As the borer followed the tree west of the Mississippi, it moved beyond the reach of its natural predator, the woodpecker. The only woodpeckers I’ve seen here not only are a different species than the red-cockaded ones in the east, but dumber: they’re always banging away on utility poles.

This year when the tree blew down, and they always do blow down, I did find someone to remove it in the short period that remained before the goldenrod started blooming. My plan was to take a strong mix of a chemical that could handle some kinds of borers, and paint the trunk and pour the remains through the holes in the top, to kill whatever was there. That operation was completed two days before rains came. Fate indeed.


Even if I can do nothing, I was curious why so many older trees near the village aren’t damaged when they’re closer to the patches of goldenrod. This spring, when they were blooming, I drove around. The largest trees had a lot of dead wood at the top, which more likely came from one of the droughts.

The man who cut my tree down, though, did say he had been getting more calls than usual to remove trees, especially those near houses. I had decided to keep mine, which are on the other side of the drive, because they can take the worst winds that come. Also, they are fragrant when they’re blooming.


After he took away my diseased wood, I started haunting a goldenrod patch trying to spot the insects. The plants are on the other side of a formidable barb wire fence, so I couldn’t get as close as a near sighted person must. And, I must admit, I have an inbred disinclination to get close to anything that resembles a wasp. So I don’t know if I’ve actually seen one of the critters or not, but I’ve seen something that looks close.


Notes:
McCann, James M. and Dan M. Harman. “Avian Predation of Immature Stages of the Locust Borer, Megacyllene robiniae (Forster) (Coleoptera: Cerambycidae),” Entomological Society of Washington, Proceedings 105:970-981:2003.

Photographs: The best photograph of a locust borer is on the myrmecos.net website.

1. Goldenrod growing along bank of a ditch under a cottonwood, 4 August 2012

2. Bee on goldenrod, same patch, 2 August 2012.

3. Unknown insect on goldenrod, same patch, 4 August 2012.

4. Evidence left by locust borers on my parent black locust tree, 8 June 2008.

5. Locust borer damage done on grown sucker of above tree, 9 July 2012.

6. Damaged black locust tree blooming, 12 May 2012.

7. Insect on same goldenrod patch, 4 August 2012, either a hornet or a locust borer or something else. I’m not an entomologist, but I thought it was a hornet at the time.


8. Black locusts growing down the road that have been able to get tall, 3 May 2012. The one has been trimmed on the left; since it’s in an open field with no utility lines, I assume the branches died from something.

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