Monday, September 30, 2013

2013 Stink-bug Damage Update

Stink bug on Golden Treasure pepper, with
serious damage beginning near stem
Damage to vegetables by brown marmorated stink bugs was “mixed” here at Meadow Glenn this summer.

Early in the vegetable growing season I noticed a stink bug or two, but not enough to concern me.  They got my attention later, however, when I found 10 or 20 on the small green pods of my two Crimson Select pepper plants—and a few more on my two Golden Treasure pepper plants.  I then closely examined my tomatoes and found a few more stink bugs.

Since stink bugs are skillful at avoiding capture when I try to remove them manually from garden plants, I had researched possible insecticides and chose bifenthrin, a commonly available pyrethroid, to spray when needed.  I follow directions to the “T” and use the longer California standard for “Days to Harvest” for both tomatoes and peppers.  So when I found the bugs, I sprayed the pepper plants carefully, and I sprayed the main stems of my 25 tomato plants and any stink bugs that I found on fruit.  I sprayed once a week another two or three times—and was relatively free of stink bugs for most of the remainder of the growing season.

“Most of the remainder” means that I didn’t notice stink bugs again until today, when I noticed two stink bugs on two of our remaining Golden Treasure peppers.  I hadn’t sprayed for more than a month.  Today I noticed two stink bugs on two of our few remaining Golden Treasure peppers.  I just squished the bugs thumb and finger—not a disposal method I recommend to squeamish gardeners or those with sensitive noses—since this late in the season I see little value in spraying again.

How much damage did my tomatoes and peppers suffer from stink bugs this year? 

Stink-bug damaged peppers,
Crimson Select (top) and Golden Treasure (bottom)
Tomatoes showed little to no fruit damage.  Loss of Crimson Select peppers has been nearly 100% on my two plants despite multiple sprays.  When the stink bugs puncture pepper cells, bacteria enter through the punctures and in most cases the peppers over time become unattractive before totally collapsing.  Even though my two Golden Treasure pepper plants were next to the Crimson Selects, I lost only two or three of the early pods, though several more showed minor damage.

Bottom line:  Stink bug news here at Meadow Glenn was good for tomatoes and bad for peppers.  Now that nighttime temperatures are sinking, we’re finding a few adults inside our house, likely looking for cozy wintertime hiding places.  Today we found four or five, and they’ve all failed their first swimming test in a bottle of soapy water.

My experience with the stink bugs in 2013 may not be typical.  J.S., a Master Gardener in Harford County—about an hour away—in an email recently told her sad story:  “I read the GIEI blog … about the wonderful tomatoes and the lack of stink bugs.  I could have cried.  I lost about 60% of my corn, all my cherries, peaches, pears, and apples and now am losing about 40% of my tomatoes to stink bugs.  I guess they just love me best.  Oh, whoopee!”

What impact did brown marmorated stink bugs have on your gardens this year?

In the Environment section of Monday’s Washington Post, Darryl Fears reviews regional stink-bug happenings in his article, “Stink bugs are plentiful in Mid-Atlantic states, and they’re ready to come indoors for winter.”

Knock, knock.  Got a cozy place for winter?

Wednesday, September 11, 2013

A Prince & Princess—and a Monarch too

A Prince--or Princess?
I must be a monarchist.  I’ve been concerned all summer because hundreds of butterflies were in our gardens—but not one Monarch.  I read emails from Master Gardeners questioning why the Monarchs had disappeared: Misuse of pesticides or herbicides?  Natural cycle?  Deforestation of Monarch wintering grounds in Mexico?  Some unknown factor?

One posting left open some hope—saying that perhaps the Monarchs were just late in migrating from their northern territories and would be migrating through later than usual.  So I kept looking for a Monarch among the many butterflies visiting our coneflowers and zinnias and at our five plantings of milkweed—Asclepias tuberosa and Asclepias incarnata—the host plant on which Monarchs lay their eggs and on which their caterpillars feed.

For weeks I found nothing.  Not good, I worried.

And then about 10 days ago I found two Monarch caterpillars chomping on milkweed leaves when I checked our two Asclepias incarnata plants, gifts of Corliss G., a Howard County Master Gardener, during an exchange of perennials. I promptly named them Princess and Prince—true offspring of Monarchs.  But where were the adults—flying about in Eastern Tiger Swallowtail disguises?

A visiting Monarch
Then for two days last week a Monarch—or was it two?—visited the blossoms of our backyard zinnias and coneflowers.

Two Monarch caterpillars and an adult or two!  I’m relieved, but how relieved should I be when I should have expected to find 10 caterpillars and seen a score of adults?

Here’s hoping I see scores of Monarchs in Summer 2014.  In the meantime, I’m thinking that perhaps I should consolidate our far-flung milkweed plantings into one or two larger beds to encourage the beautiful insects to stop here at Meadow Glenn for some fast food on their annual travels.

P.S.  Today’s (Sept. 12) Local Living section of the Washington Post contains three articles by Adrian Higgins on butterflies, bees, and other pollinators.  Click on the blue to go to “Creating a haven for butterflies and bees” (subsections on Monarchs, Honeybees, Bumblebees, and Pesticides); “Planting and gardening for pollinators” (breaks down common pollinator-supporting plants into these lists: “Milkweeds,” “Trees and shrubs,” “Herbs,” and “Perennials” and then Spring, Summer, and Fall bloomers); and “Tips on beekeeping” ( lists local beekeeper organizations).