Friday, May 15, 2009

Stinkhorns!

Walking the dogs around the yard this morning I saw a clump of my favorite fungus, stinkhorns. I like these because they remind me of a line in that old TV show, Wings.

The line is spoken by the ditzy lady (Faye) behind the ticket counter. She is entertaining the waiting passengers with fun facts, and one is something like, “the pressure from a whale’s blowhole can shoot a baby 23 feet in the air” (I know the height number isn’t right, but the idea is). Then she says, “Isn’t mother nature a hoot?”

When I see stinkhorns, I think that line.

Sometimes the taxonomists do a good job of assigning helpful names, and the family name of the stinkhorns, Phallaceae, is an excellent example; they are all a bit phallic in appearance. Of course, the stinkhorn family contains many species, but I’m pretty sure the stinkhorns that pop up in my yard are Mutinus caninus (also called the dog stinkhorn; they aren't as tapered as M. elegans).

My 1979 copy of Ian Ross’s book Biology of the Fungi includes a little stinkhorn-related story from a 1959 text by Wasson and Wasson, about Charles Darwin’s aunt. The story is that she “used to seek out and destroy such horrible growths from the neighboring woods, so that when the maids of the household went out for walks, their morals would not be impaired.”

The commentary that follows the story is also interesting: “One assumes, of course, that Darwin’s aunt was, as are all censors, incapable of being affected by such gross objects.”

According to Kerry's Garden, the dog stinkhorn is edible. A comment under the post by Jim Krupnik adds that it is also considered a delicacy by the Chinese. It is possible that stinkhorns are the plant world's version of Limberger cheese. My in-laws used to say that the trick is getting it past your nose---then, it is pretty good. Needless to say, I never got that stinky cheese past my nose. I think the stinkhorns are going to stay out of my kitchen, but it is good to know that they aren't at all dangerous.

Monday, May 4, 2009

Pest Control: Cucumber Pickleworms

Planting time is a good time to think about pest control, so I looked up the UGA fact-sheet on growing cucumbers and found a warning about cucumber beetles—keep them under control (through unspecified means) because they spread disease. That could be a useful warning, but I am pretty sure I have never had a problem with cucumber beetles. My pest problem in cucumbers is cucumber pickleworms .

Last year, the cucumber pickleworms had a very good year, and my cucumbers had a correspondingly bad year. Almost all of my cucumbers had the little shot-holes that show where a larva has eaten its way into the fruit. The little pests were also worse than usual at the Plant a Row for the Hungry garden where I volunteer, so I know the problem was not just in my yard.

I have a copy of The Organic Gardener’s Handbook of Natural Insect and Disease Control , and when I realized the cucumber harvest was in serious jeopardy I checked the pickleworm section for advice. One suggestion was to plant a “trap crop” of yellow squash, since the pickleworm likes those even better than it likes cucumbers. The other advice was to plant early maturing varieties of cucumbers so that a good harvest could be brought in before the pickleworms totally demolished the crop.

This advice might have been useful a couple of months earlier (at planting time!), but it didn’t help much at the time. However, spring has come around again, and I have another chance. I am not changing my cucumber varieties, though, because they already are varieties that mature fairly early, and I don’t really have the space for trap-crops, other than the zucchini that usually keels over before the onslaught of the pickleworm, so I am hoping for a different solution.

The Pickleworm Management page from North Carolina State University, recommends the use of Sevin (carbaryl) to manage pickleworms. People who are averse to using pesticides (even this one which is a relatively safe chemical for home gardeners to use), are going to hope for another option.

According to the fact sheet Cucumber, Squash, Melon & Other Cucurbit Insect Pests from Clemson University, pickleworms don’t survive winter freezing, and the adults fly up from Florida each year:


“In South Carolina, pickleworms starve or freeze to death during the winter. They overwinter in Florida and spread northward each spring. Severe damage usually does not occur before summer in South Carolina. Heavy populations generally do not build up before the first flower buds open; however, late crops may be destroyed before blossoming.”


It seems reasonable that when the Southeast has an early or unusually warm spring, or early, strong winds heading north out of Florida, the pickleworm damage might start earlier than usual, like it did last year.

A couple of those linked resources also mention that the parent of the pickleworm is a night-flying moth. This seems like information that could be used to thwart those pickleworms. I am thinking about covering some of my plants at night, to keep the moths from laying eggs on my plants, then uncovering the plants in the morning, so bees and other pollinators can get to the flowers.

This sounds like work, I know, and some of my cucumbers will be trellised and a serious hassle to cover up each night. So, I will leave the trellised vines uncovered and only cover the pickling cucumbers that will be sprawling on the ground this year. This way I will have both an experimental plot--covered-- and a control plot--uncovered-- (ignoring that they are different kinds of cucumbers), so the experiment may be able to tell me whether the nighttime covering makes a difference in pickleworm infestation.

I’ll let you know how the experiment turns out.