I started thinning peaches when most were the size of marbles. At the beginning of the peach-growing season, some of the fruit already had two to three sting marks on the skin. As the thinning period progresses, peaches almost the size of golf balls are showing three to four sting marks. Immature green and mature gray stinkbugs crawled on my arms and down my neck as I worked.
The worst infection appears on trees closest to the barn, where the adults over-wintered under the roofing and in the cracks and crevices in the wood. My rough estimate is that five to 10 percent of the fruit has been punctured. It is easy to tell that the stinkbugs are very active because many of the fruit are leaking clear liquid from recent punctures.
Stinkbug punctures drastically reduce the quality of fruit. When the stinkbug punctures the fruit, it releases into the flesh glycol that will later cause a distortion. The tissues in the affected area do not ripen like the rest of the fruit, which means that only part of the fruit is edible. If the fruit is punctured several times, the peach will produce a feature resembling a cat’s face; thus the symptoms are called cat facing.
Last year, I discarded at least two percent of the fruit harvested due to cat facing. I will be discarding many more fruit while grading peaches after picking, and buyers will have great difficulty finding perfect peaches.
Some pesticides can be used to kill stinkbugs, but they lose their potency rapidly, thus requiring frequent applications. Economics and safety can make it impossible to grow perfect peaches. Growing quality peaches requires 10 to 12 spray applications per season — and that’s without stinkbugs. It is difficult to justify additional sprays with a growing number of buyers looking for residue-free fruit.
Peaches cannot be grown organically because of their susceptibility to diseases and insects. The stinkbug has made growing peaches ever more difficult. This could be my last year for growing peaches.
Does Rose Calamity Mean Chemicals?
Q: Seven of my more than three-dozen rose bushes sprouted odd new shoots from the old canes. These new shoots are thicker than normal and are red, like new growth, except they remain red. The tops resemble witches brooms with gnarly leaves and tight little buds that never open.
I’ve been told these roses are infected with the deadly rose rosette disease. I understand it is extremely contagious, and the infected plants must be removed immediately or I risk infecting the entire rose garden.
I’ve learned that the virus is carried by the eriophyte mite, which is killing off the wild floribunda roses abundant in fields around my house. The mites are wingless, so they catch a ride on the wind, blowing around looking for another host. I’ve been warned to watch my apple and pear trees, too, as they’re in the same family as roses.
A neighbor five miles from me found the same thing on one of her roses. Is this a widespread regional problem? Should I be concerned about losing my entire rose collection?
I have never used chemicals in our yard, but with many hundreds of dollars and many years invested in my roses, I probably will.
–Margaret Tearman, Huntingtown
A: You had better control the carriers by either spraying weekly with malathion or with Baker’s Disease and Insect Soil-Applied Rose Pest Control.
RRD can also be transmitted by the rose chafer, which is a chewing insect that may require you to also apply Sevin if you do not use the Baker product.
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