A Vacation and a Trip
By Andrea Peck
I recently took a staycation to visit my family in San Simeon. My kids and I rode the Route 12 bus to Morro Bay where we had a layover of about an hour. We treated ourselves to a Foster Freeze ice cream and visited a thrift store before catching the Route 15 bus to our final destination. Despite our odd baggage of flip flops and scuba gear, toothbrushes and my son's innovative sock-knot on the outside of his backpack, we were a tidy threesome. Somewhere along the line we lost the orange yarn that my son makes braided bracelets with. Luckily it had only been $1.00 at the thrift shop.
The following day we spent wandering from beach to parking lot to restaurant—the town, tiny and manageable, lent itself well to a small bipedal family. The short curb-to-curb distances encouraged detail watching. My mother and I marveled at the number of cigarette butts. At some point my father pointed out the dominant landscape of Myoporum trees, trimmed to bush size. I have a particular fondness for Myoporum, somehow they remind me of my third grade year in Huntington Beach. A few years back, we had to cut down our own Myoporum trees. I felt sorry that things could not have continued on, but both trees had a horrible case of thrips and they both sat where the new sewer will someday be attached.
Seeing these decrepit, thrips-ladden trees in San Simeon brought back that same saturnine sense of loss, perhaps even more vividly than I experienced at the official tree cutting. The perpendicular passage of time seems at these moments to sharpen and focus. Amongst the interested adults, there was some discussion about thrips—my dad insisted that the use of pesticides or the relief of the drought could possibly bring the trees back to a healthy state. It made me wonder. What's happening with thrips now? Have things changed? Has someone come up with a sensible treatment plan?
If you have not been introduced to thrips, you should know that there are many kinds. They are small (about 2.0-2.5 mm long), thin and range from dark brown to black. The type we are talking about is officially named Klambothrips myopori. This type of thrips attacks Myoporum laetum and Myoporum pacificum to be specific. Thrips feed on the leaves, causing the foliage to curl and twist. Of course, this is no way for a plant to thrive, so inevitably the leaves and branches turn brown and die. Thrips can breed quickly, having many generations yearly. Warm weather brings rampant breeding. Oh, joy.
Because thrips inhabit the inner curls of the leaves, control of the pest is difficult. If you are OCD, (and have the time) monitor the plant before it becomes infested. You may be able to get to the thrips before they recess themselves in a leaf bunker. But, remember, though it may sound doable on paper, tiny insects often win those fights. There are natural predators, minute pirate bugs (Orius spp.), green lacewings (Chrysopa and Chrysoperla spp.), and several other species that help to control myoporum thrips. Nevertheless, these beneficials may be severely outnumbered.
Resorting to contact insecticides will likely end in frustration—these cannot reach the inner thrips sanctum. Dinotefuran, which must be applied by a licensed pesticide applicator, has shown some promise. Still, resorting to draconian methods in an effort to save an ornamental memento may not be the best choice. These pesticides greatly harm other beneficials and pollinators that may reside in the neighborhood.
In the end, it appears that not much has changed: thrips are here to stay and systematically destroy this coastal icon. Perhaps the most logical solution is to plant a variety of Myoporum that is not susceptible to thrips. Flexibility, we know, is often the most sensible solution.
Two plants I found that may be good replacements are Griselinia littoralis and Laurus nobili (sweet bay). These two, when viewed from a distance (particularly if your vision is aging like mine) may remind you of those youthful days. And then you can have the best of both worlds—a trip down memory lane without the tiny insects.