At the Pollinator Symposium at the Monastery of the Holy Spirit this past weekend, attendees learned about urban bees, pollinator plantings along roadsides and around retention ponds, and about plant-pollinator interactions. The event was amazing!
Of course, I am on the committee for Monarchs Across Georgia, the group that organized the symposium, so I might be biased.
Dr. Jaret Daniels, the first presenter, is working in Florida with the Florida Dept. of Transportation to find the best mowing schedule for roadside wildflower plantings in that state. Dr. Daniels reported that the state DOT mostly keeps an every-3-weeks schedule for much of the mowing. For the 12-or-so feet nearest the road, the vegetation needs to be kept short for safety reasons.
He has found, though, that for parts of the verge further back from the road, 6-weeks between mowing allows more plants, and more kinds of plants, to flower (all good for pollinators!). In talking with state officials, he found that “protecting monarch butterflies” was a better motivator for trying a longer mowing cycle than “saving money.” Everyone wants to be seen as a friend of the monarch!
Dr. Jennifer Leavey, working at Georgia Tech to understand how urban environments affect bees, suggested that flowering trees are a great supplement to our small pollinator gardens. Each flowering tree provides many more flowers than a small garden, even though a tree may flower for only a few weeks. The key is to make sure that enough flowers are available to pollinators through the entire growing season to support bees over many months.
She showed us a graph of information, developed by her students with information from Trees Atlanta, that showed most of Atlanta’s flowering trees are blooming in April. Apparently, we need more trees that flower in other months.
Dr. Tim Spira is a (recently retired) plant ecologist whose work has focused on plant-pollinator interactions. His information was less practical, in some ways, since much of what he told us isn’t “things to do”. It was more, “how this works, and why.” However, his talk contained the most fun-facts.
Example: Usually, pollination is a happy accident that occurs when an insect or animal pokes its head inside a flower to plunder the nectar or pollen. Some of the pollen ends up on the insect/animal, and when that individual visits another flower in search of more good food, the pollen from the first flower brushes onto the female parts of the second flower. If the two flowers are for the same kind of plant, voila! Pollination can occur. He told us, though, about one pollinator that moves pollen onto the female parts of a flower on purpose, with pollination as her primary goal. This pollinator is the yucca moth (link to US Forestry Service information).
She gathers pollen from one yucca flower, then flies to another flower where she lays eggs inside the ovary of the new flower. Then, she uses her wad of gathered-up pollen to pollinate the flower where she has laid her eggs. When her eggs hatch, the babies will eat seeds of the yucca fruit that develops from the pollinated flower.
All in all, it was a great day. My little presentation about systemic pesticides seemed to go well, and I had fun visiting with other gardeners and people who love pollinators. Of course, very few people place the flower flies quite so high on their list of favorite insects as I do, but someday that may change.