October 15, 2019 at 11:50 am
By Wildlife Biologist Sarah Spencer
Back in 2012, I discovered that my septic was failing and required an overhaul. Although it was a major inconvenience familiar to many residents of rural areas, it turned into a success story for pollinators!
We knew woody plants would need to be kept from growing in the leach field, but we didn’t want more lawn to mow, so we settled on a goal of providing a mix of flowering plants for as much of the growing season as possible without introducing any invasive plants.
Fast forward to the 2013 growing season. The results were less than exciting. The patch looked like a sparse, unmowed lawn--but I was reminded to be patient. Many perennials require several years to become well-established. Each year afterward, this modest patch would show us a little more in terms of flowering plants and the pollinators visiting them. By the fifth growing season, our leach field finally turned into exactly what we’d been hoping for all those years before. But there was still something missing.
Though other pollinators frequented this patch, we hadn’t seen any monarch butterfly adults or signs of their larvae despite having their host of milkweed present.
2019 seemed to be a great year for monarchs, a charismatic species and a symbol for pollinators across North America. I heard anecdotal stories from across Maine about all of the monarchs people were seeing. On a Saturday afternoon, I watched an adult monarch elegantly flying around our little flower patch, landing and delicately depositing one egg at a time on the underside of a milkweed leaf. I shouted with joy (really!) and watched eagerly over the following weeks as eggs continued to appear, hatch, and grow into beautiful larvae.
As they grew larger, the largest ones started to disappear, then reappear as a pupa, sometimes hanging several hundred feet from the milkweed where they fed. When we had our first hard frost of fall, I worried the remaining pupae wouldn’t survive. On October 6th, I checked on a pupa dangling from a cobweb attached to the siding of my house. To my surprise, I found an empty pupa and an adult monarch on the ground exercising its wings.
To keep woody plants from establishing in the leach field, we mow 1/4 to 1/3 of the area each year, usually in late November, offering protection for species overwintering as pupae in the unmowed areas.
If you’re interested in more information about creating a landscape for butterflies, The University of Maine Cooperative Extension Bulletin #7151 will give you just that. For more information on invertebrate conservation, visit xerces.org.