It’s planting time here in NE Iowa, and lots of us are busy readying our garden beds. Many of us pick plants that would grow well in a particular sun or shade site; some of us pick flowering plants that will be beautiful in our annual and perennial beds. The environmental problem is the use of chemicals to treat farm crops. Many garden plants for sale, particularly at big-box stores, have been pre-treated with insecticides and pesticides that harm and even kill pollinator species, which include some birds and bats, but the greatest number are insects: bees, butterflies, flies, wasps, and beetles. To fight this problem is a big job, but each of us can do our part by being careful that we purchase, preferably at greenhouses, native and pollinator-friendly flowers. It’s also helpful to make nest sites available, avoid using pesticides yourself, and spread the word to others about these steps. What plants are both native and pollinator-friendly in our area? There is a long list that includes various types of milkweed, clover, thistle, blazing star, coneflower, ironweed, dropseed, sumac, aster, goldenrod, and phlox. Various websites have much more specific lists: one pdf. list for the Midwest is at the following site: https://xerces.org/sites/default/files/publications/22-025_01_NPPBI%E2%80%94Midwest_web.pdf.
What about pesticides? The most common problematic insecticides to know about are neonicotinoids and glyphosates. Farmers use neonicotinoids to control sucking insects. Because neonics are systemically absorbed, they can affect all plant parts, including the blossom and pollen. They then attack the nervous system of the pollinator; this is considered by many to be the cause of the current epidemic of honeybee hive collapse across the country. Glyphosate is another synthetic chemical used in many herbicides, including Roundup, which is applied to agricultural crops but also used in lawns and gardens to control broadleaf weeds and grasses. The EPA considers this chemical unlikely to be carcinogenic to humans, but many lawsuits have claimed that the chemical caused non-Hodgkin’s lymphoma. For that reason, some companies have taken these products off the market. There is a strong argument that the use of glyphosates caused a drastic drop in the population of an important pollinator, the monarch butterfly, by eliminating its primary food source, milkweed. As the use of glyphosates increased and milkweed died out, the count of monarchs dropped drastically.