By Jennifer Weeks
As spring expands across North America, trees, shrubs, and flowers are releasing pollen. This fine, powdery substance is produced by the male structures of cone-bearing and flowering plants. When it’s carried to the plants’ female structures by wind, water, or pollinators, fertilization happens.
As pollen travels, it also triggers allergies in some 25 million Americans. Pollen exposure can cause sneezing, coughing, itchy eyes, runny nose, and postnasal drip — unwelcome signs of spring for sufferers. This roundup of articles in the Conversation describes recent findings on protecting pollinators and coping with pollen season.
Hey pollinators, over here
Since pollen grains carry the cells that fertilize plants, it’s critical for them to get where they need to go. Often wind or gravity is all it takes, but for many plants, a pollinator has to carry the pollen grains. Some plants offer nectar or edible pollen to attract insects, bats, or other animals, which carry pollen from plant to plant as they forage. Many flowers also lure pollinators with scent.
“Similar to the perfumes at a department store counter, flower scents are made up from a large and diverse number of chemicals which evaporate easily and float through the air,” writes Mississippi State University horticulturalists Richard L. Harkess.
Bees at the buffet
Many species of insects have declined in recent years. One big focus is honeybees and other species of bees, which pollinate many important crops.
In a 2021 study, University of Florida agricultural extension specialist Hamutahl Cohen found that when bees visited fields where sunflowers, grown as crops, were blooming over many acres, they picked up parasites at a high rate. In contrast, bees that foraged in hedgerows around crop fields and could choose from diverse types of flowers to feed on spread out farther and had lower rates of infection.
Warmer temps, more pollen
As climate change raises average temperatures across the United States, growing seasons are starting earlier and ending later in the year. That’s bad news for allergy sufferers.
“Southeastern regions, including Florida, Georgia, and South Carolina, can expect large grass and weed pollen increases in the future,” University of Michigan atmospheric scientists Yingxiao Zhang and Allison L. Steiner said. “The Pacific Northwest is likely to see peak pollen season a month earlier because of the early pollen season of alder.”
Pollen season is also gardening season since it’s when plants are blooming. West Virginia University mycologist Brian Lovett offers advice for gardeners who want to attract beneficial insects to their yards for pollination and other purposes.
One step is to replace grass with native wildflowers, which will provide pollen and nectar for insects such as ants, bees, and butterflies.
(Courtesy: The Washington Post)