A bee moves Sept. 18, 2018, between blossoms in a clump of New England asters on Civic Center Drive in Augusta. The flowers are noninvasive perennials that are native to Maine. Joe Phelan/Kennebec Journal file

AUGUSTA — A proposed policy would ban the city from the planting of non-native plant species as part of a new effort to foster food sources for animals.

The proposed policy, under consideration by a newly active Augusta Conservation Commission, would require all future planting efforts by the city of Augusta to be species native to the region. Exceptions would be made for decorative annuals, plants for food and sports fields or lawns, and the proposal would not apply to residents or businesses.

Aaron Sienkiewicz, chairman of the Augusta Conservation Commission, which was reformed after falling largely dormant during the COVID-19 pandemic, told city councilors many of the non-native plants people purchase commercially and plant cannot be eaten by native insects, which are a major food source for animals that rely on insects to survive.

Sienkiewicz said the global insect population is dropping every year, leaving less biomass for animals to eat. Invasive plants, which often have no natural competition, grow well and quickly and squeeze out native plants that are relied upon by native insects, he said.

He said a single pair of nesting chickadees must find an average of 7,000 caterpillars to feed their young in the roughly 18 days the young are in the nest between hatching and taking flight. With fewer native plant species around for insects to eat, there will be fewer insects around for other animals to consume.

“The big deal with non-native plants, or invasive species, the plants that don’t come from this area, (is they) can’t be eaten by our native insects,” Sienkiewicz said, adding that he is including caterpillars, bugs and spiders as insects that need native plants to eat. “Things like (non-native plants) butterfly bush or burning bush, they help pollinators, but that is only part of the equation. We need to be able to provide the green biomass for things like caterpillars to eat.”

At an informational meeting last Thursday, Augusta city councilors said they support the idea. One councilor suggested taking the anti-invasive plant fight a step further by having the zoning ordinances require developers use native plants when a project requires grassy space.

“A lot of the development, it does require green spaces. Perhaps part of our requirement, in those green spaces, also could be to use native species,” said Ward 2 Councilor Kevin Judkins, who also suggested the commission consider partnering with the schools to potentially create a greenhouse where students could help grow and propagate native species of plants.

Sienkiewicz said he hopes the commission can also find ways to help residents find and acquire native plants. He said big-box stores oftentimes do not carry them, and they can be hard to find even at local greenhouses.

Sienkiewicz also recommended the city consider using pesticides to kill invasive plants, suggesting a targeted method of cutting down an invasive bush or other plant and immediately painting it with a high concentrate of pesticide. He said this is a safer method than widespread spraying.

“What that does is get you away from just spraying, which has a lot of negatives to it, and concentrates it where it needs to be,” Sienkiewicz, who is the husband of At-Large Councilor Stephanie Sienkiewicz, said of the “cut and paint” method of using pesticide.

“If you take something like bittersweet, or multifloral rose, and you just cut it, you may start with one stump and end up with 20 the next year, because if you don’t kill the roots, it really comes back with a lot of energy.”

City Manager Jared Mills said city use of pesticides can be controversial, but city staff members could research the issue and officials could then have a discussion on the proposal.

Editor’s note: This story has been updated to more clearly state the policy proposal would apply only to the city of Augusta, and not residents or businesses.