Sunday, January 21, 2007

CSI: In My Garden

The January Herb Study at the GCHS was Echinacea.
To paraphrase an old television drama "There are a million stories in the" "here is one of them..."

A few years ago I began to notice some significant problem with my purple coneflowers. What! Nothing bothers purple coneflowers! Right!?!

BUT, if something is gonna happen in way of a garden disaster large or small, it'll happen to me.

On closer inspection of my blighted flowers, all of the the ruined cones seemed to be damaged in the same way... blackened broken centers. I cut off the worst flowers and brought them indoors and dissected them on my kitchen counter. Eyuck, small wormy creatures had burrowed straight down from the tip of the seedhead right down into the stem. I took some photos with my first generation digital camera and went out to the garden and deadheaded all of my Echinacea. Dejectedly. I love purple coneflowers.

I couldn't find any clue in my books, or the books at the Extension, or
online, or by asking around. Closest I could figure was a hint from several online sources that certain flowers attract the European Corn Borer, the timing was right, and the damage was identical. It fit the profile of a native plant being decimated by an imported pest, especially because the pest was probably under pressure from all of the cornfields that have surrounded my neighborhood being bulldozed for new subdivisions. But I was still unsettled about it. The little larvae I had didn't look right, I was seeing stripes and the ECB is spotted. I knew from my time working with the Diagnostic team that the distinction was important. All burrowing larvae are not the same.

I even asked flower experts at conferences. Apparently I didn't paint a grim enough portrait of the damage these flowers were suffering. No one knew or cared. Years passed. I deadheaded as needed, dejectedly.

January 2007, the Genesee County Herb Society's herb study will be Echinacea. It's January, time to read with a purpose! Looking through my coneflower photos from years past, the CSI photos sparked my interest in finding the name of that little grub.

I Googled around and came across a paragraph in a paper I downloaded from the Connecticut Agricultural Experiment Station, entitled Perennial Medicinal Herb Trials 1996-1999. On page 7, under Echinacea purpurea L. Moench. is this sentence:

"Echinacea is a member of the aster family, and susceptible to the same insects. Sunflower moth larvae damaged more than 80% of blooms cut in late summer."

Googling furiously, I brought up: "Sunflower Moth" page 3 on a publication from the Maryland Cooperative Extension with a GREAT PHOTO!

Identification of a pest is the first step in IPM. I feel much better.
Now I have to figure out how to save my purple coneflowers from this particular larvae.

NOTE: Cross-posted to The Backyard Herbalist

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