Emerging from a summer that offered plenty to complain about—unseasonably warm early temperatures followed by drought –then prolonged heat extreme even for the height of summer—it’s small comfort to learn that this season’s weather appears to be part of a larger trend. As the authors—all researchers in the earth and climate sciences– of a recent Opinion piece in the New York Times stated, “it is increasingly clear that we already live in the era of human-induced climate change, with a growing frequency of weather and climate extremes like heat waves, droughts, floods and fires. Indeed, assuming business as usual, each of the next 80 years in the American West is expected to see less rainfall than the average of the five years of the drought that hit the region from 2000 to 2004. That extreme drought had profound consequences for carbon sequestration, agricultural productivity and water resources: plants for example, took in only half the carbon dioxide they do normally, thanks to a drought-induced drop in photosynthesis.”
We may comfort ourselves that is not an east coast problem yet, but there’s bad news closer to home too. Connecticut Agricultural Experiment Station researchers confirmed this June that Boxwood Blight (Cylindrocladium pseudonaviculatum) once limited to Boxwood (Buxus) and Sweet Box (Sarcococca) was found infecting Pachysandra (Pachysandra terminalis). The Pachysandra bed was located next to newly planted Boxwood plants that appeared infected—and were apparently the source of the disease. Although researchers had proven previously in experiments that Pachysandra was a potential host under the right conditions, this was the first time such an occurrence took place under naturally occurring conditions. All three plants are members of the Buxaceae.
Particularly devastating to greenhouse growers this past season, Impatiens Downy Mildew (IDM) is a pathogen that destroys Impatiens walleriana plantings overnight, causing all leaves and flower petals to drop. It favors wet, cool conditions–infected plants don’t survive, and must be disposed of immediately. Prevention is considered the best remedy; overhead watering– especially during cool weather–should be avoided. IDM doesn’t seem to survive in the soil and does not affect New Guinea Impatiens.
My husband, descendant of a long line of accomplished gardeners, reminds me that we must remain optimistic and not be discouraged by the scourge of the moment. Remember Gypsy Moths, and how it was forecast some decades ago that they would destroy all our deciduous forests? Well, they left enough leaves on the trees so that deer (Odocoileus virginianus) can do that for us now.