scientists are saying that folks should be cautious in using pesticides, as
pollinators feed on many of the weeds which lawn owners use poison to kill.
weeds may be unsightly to you, they’re food to bees and other pollinators,
the researchers report. If you must spray, mow the weeds down first to
remove the flowers, according to an article published in the Journal of
Integrated Pest Management (JIPM). The guide also outlines other
recommendations to protect pollinators, including preferred times to apply
It’s important to
consider the consequences of treating your flowers, including flowering
weeds, said Doug Richmond, an associate professor of turfgrass entomology
and applied ecology for Purdue’s College of Agriculture. “We must understand
that there are some tradeoffs,” he said. “These pollinators live in our
urban environment. There are many ways we can expose them to pesticides
unintentionally. If you spray your flowers to protect them from pests, you
may be increasing the chance that pollinators will be exposed to that same
often think of clovers and dandelions as weeds that need to be destroyed,
rather than flowers that attract pollinators, said the guide’s lead author
Jonathan Larson, a extension educator for the University of
Nebraska-Lincoln. “If you’re going to treat your lawn for pests, consider
the effect on pollinators,” she said. “A lot of people often forget that
weeds like dandelion and clover are flowers, resources for pollinators. We
tend to think of roses, lilacs and violets as flowers.”Ê
made by the guide:
* Wait until May or
June to apply pesticides. Early-season pollinators and colonies of bees are
still recovering from winter stress in March and April.
* Use granular
formulations of insecticides, which fall to the ground and avoid direct
contamination of flowering portions of blooming plants.
* Select and plant
grass breeds that are resistant to pests.
* Maintain a high
mowing height for grass to promote deeper root systems and enhance tolerance
to stress and injury from pests.
biological control agents, such as parasitic nematodes and fungi that attack
pest insects but are generally safe for non-target organisms.
* Establish plots
of pollinator-friendly plants, which is an increasingly growing practice
among golf course managers and homeowners.
spending about $75 billion a year on lawn care expenses, the impact of
certain lawn care practices on pollinators could be more far-reaching than
scientists realize. Richmond said there hasn’t been extensive research on
the effect of urban lawn care practices on pollinators, an increasing source
of concern among scientists because of their vulnerability to environmental
Richmond and Larson
stressed Americans may need to change their definition of a perfect lawn.
“We have been convinced, over time, that a perfect lawn is nice, green, lush
and completely uniform with no other plants,” Richmond said. “But that’s
perfect for what? It’s a human construct.”
that a “perfect” lawn, which includes turfgrass and other plants, should be
considered one that is beneficial “for filtration, cutting down on the heat
in urban areas and serving as a habitat for pollinators.”
Larson, who noted
that he doesn’t treat his own lawn with pesticides, said many Americans
aren’t satisfied until their lawn looks like a golf course. “Understand what
your lawn is for. If you want it to look nice, there are more sustainable
ways of doing it.”