Pale purple asters and milkweed. Copyright S. Klink.
Surrounding my mowed lawn is a wild, mostly uncultivated space that currently has goldenrod blooming with tall asters starting to blossom. Every day when I pass these flowers, I see bumblebees, butterflies and other insects collecting the nectar to eat or store for the winter. Last year, when a section of soil was disturbed during construction of a building, I decided to seed the area with native wildflowers rather than grass. (I am not a fan of mowing the lawn.) Watching the series of flowers bloom over the late spring to autumn has been beautiful, colorful and full of tiny moments of joy. Not only do I see insects enjoying the flowering plants, but birds will land on the taller greenery, sometimes just resting, sometimes collecting seeds. I am not sure who has been startled more often, me or the birds when I walk by, flushing a bird from the thicket of tall plants.
Monarch butterfly on thistle photographed in the prairie at Promega headquarters in Madison, WI. Copyright Promega Corporation.
Where some people might see wild, unruly areas, I see Monarch butterflies on their daily flight, fluttering above me and the “weeds”. I have even been lucky enough to find Monarch caterpillars munching on milkweed, a common plant in my wild space. Despite my efforts, I have a lot of tall ragweed appearing in my yard, but have discovered that birds love the seeds, including my chickens, and squirrels will remove and eat the leaves. In addition, I see fireflies in early June through late August, many I find hanging out on the shady greenery during the day before their light display at night. Continue reading
Bumblebee on clover.
Some people like a perfectly green carpet of grass; I welcome the biodiversity of clover, dandelions and other weeds (although I could do without the painful thistles). Of course, I also notice many pollinating insects including bumblebees seem to enjoy visiting the flowers that bloom in the lawn. However, concerns have arisen over the use of insecticides and the health of our pollinators. There has been extensive talk about the collapse of honeybee colonies and declining populations of native pollinators like bumblebees. One area of research is the use of insecticides, especially neonicotinoids, and how they affect bees but most studies were done in lab environments, not in a lawn where the bees would collect nectar from flowering plants. Larson, Redmond and Potter decided to study both clothianidin, a neonicotinoid insecticide, and chlorantraniliprole, an anthranilic diamide, and examine how the insecticides affected bumblebees that foraged on treated lawns.
Neonicotinoids are systemic insecticides that are potent selective agonists of nicotinic acetylcholine receptors in insects, and are applied as sprays or granules during the spring for control of root-feeding grubs and other pests. Anthranilic diamides are a new class of insecticides that activate insect ryanodine (calcium channel) receptors and cause lethal paralysis in sensitive species. Chlorantraniliprole shows low acute bee toxicity, a promising development, but this anthranilic diamide has not been tested in the field. Continue reading