The peas are planted, the beans are watered, tomatoes are towering, and the basil is in. Gardening season has begun in full force, which means that I am feeling happier and smarter than I have all winter. This is not just an anecdotal “I love gardening” testimonial – there is scientific research to back up my claim.
During those long hot hours I spend toiling in the dirt, my body is synthesizing vitamin D. This fat-soluble compound is linked to depression prevention, immune system strength, bone health, and more. I cannot quite do photosynthesis like my tomatoes, but at least I can make something useful from sunlight!
It is not just the sunshine that makes gardeners so happy this time of year; it is also the fresh air. We inhale an elixir of happiness from the soil. A common soil bacteria – Mycobacterium vaccae – has been shown to increase serotonin (a happy chemical in your brain) levels in mice. Not only does this decrease anxiety, but it also makes the mice smarter!
Mice given the bacteria navigated a maze twice as fast as the control mice. The effects do not last long, though, and scientists surmise that humans would need to be exposed about once a week in order to reap the benefits of these healthy bacteria.
Unfortunately, gardening season coincides with another season as well. Everywhere that clean, fast-flowing streams laugh and tumble down rocky paths, tiny larvae cling to the submerged surfaces of rocks and logs. At the business end of the tiny, worm-like creature is a pair of foldable fans. These fans strain passing debris from the fast-flowing water and the larva scrapes a snack into its mouth every few seconds.
After seven to ten days of eating and growing, this little larva will pupate (like a butterfly spinning a chrysalis). The creature spends a week in the pupa, completely rearranging its body and developing the tools for a new way of life. Then, in bubble of air, an adult black fly rises to the surface.
If it is a male black fly, we can pretty much ignore it. Males eat a little nectar, fertilize a female in flight, and die. Females may also use the sugary liquid to fuel their flight, but making eggs requires a blood meal. This is where gardeners, paddlers, hikers, anglers, and other outdoor enthusiasts come in. The black fly female will slash a little cut in your skin, inject an anti-coagulant with her saliva, and drink her fill. No matter that her “fill” is approximately 0.00006 ounces, the bite’s ill effects loom much larger. We end up with bleeding, itchy, swollen welts around wrists, beltlines, necklines, hairlines, and ankles.
Nothing in nature is all bad, though. These tiny tormenters feed tasty trout, beautiful birds, dashing dragonflies, and swooping swallows. Folklore claims that black flies pollinate blueberry flowers and improve fruit-set, but the scientific jury is still out on that one.
In Maine, the Black Fly Breeder’s Association sells humorous t-shirts and donates the money to charity. One t-shirt design lauds black flies as “defenders of the wilderness,” due to their ability to keep timid tourists at bay.
Despite the good qualities of black flies, we would all probably prefer to avoid them. Happily, they do not sneak indoors like mosquitoes, but indoors is not where the vitamin D and happy soil bacteria live. Dark colored clothing, carbon dioxide, and perfumes all attract them. So it follows that if we would like to deter black flies, we should wear white, not exhale, and not wash our hair or use deodorant. As a side effect, many friends and colleagues will avoid us, too.
After five or six hot days, the tender little bodies of black flies (one sixth of an inch long!) dry out and black fly season will be over.
Later in the summer, as my tomatoes ripen and the pea pods swell, I will be able to enjoy the sunshine and soil bacteria in an enlightened state of peace and happiness…interrupted only by the painful bite of horseflies.