For many homeowners, raking leaves is an autumn ritual that ranks with watching football, carving pumpkins and drinking cider.
But with deciduous trees now dropping their sunlight-snagging, sugar-synthesizing tissues, Nebraska Extension is encouraging people to consider turning over a new leaf by leaving them alone — or, at the very least, not treating them like garbage.
Green and her fellow extension specialists have launched a social media effort to buck that convention by educating citizens about the upsides of letting leaves lie. Though those advantages are manifold, Green’s mind naturally goes to the minute, many-legged beneficiaries that take to the leaves for protection.
“As an entomologist and an animal lover, there are going to be some really cool bugs that are overwintering under those leaves,” she said.
Among them are butterflies and moths — often in caterpillar or pupa form — seeking shelter under the insulating blanket of leaves that descend from on high in tandem with the autumn temperatures.
The mourning cloak butterfly, luna moth, eastern comma butterfly and banded wooly bear caterpillar rate as just a few of the pollinating insect species that overwinter within the leaves, Green said. Queen bumblebees that burrow just inches into the ground ahead of hibernation can benefit from the extra warmth, too. Millipedes, sowbugs, pillbugs, beetles and other arthropods that nourish young birds in the spring also tend to take refuge there.
Still, Green acknowledged that asking people to leave their leaves completely untouched is not always a realistic proposition. Mowing over them, but leaving the remnants on a lawn, can produce an easy-does-it layer of organic material that returns valuable nutrients to the soil, she said.
“If you’re mulching it up and putting it back into the environment,” she said, “it’s like nature recycling itself.”
That’s especially preferable to bagging the leaves and trashing them, Green said. Unlike leaves or leaf remnants left to decay on the ground, those that wind up in a municipal trash heap can often be deprived of air and consequently produce methane, a potent greenhouse gas. Burning them, meanwhile, releases carbon monoxide and other polluting gases, some of which are carcinogenic.
“We do what we can — what’s practical, what’s good for the environment,” Green said. “We’re not trying to preach about it. But it’s important to make people aware that leaving some leaves in the right places can be a good thing.
“I think the most important thing is not taking something that can decompose into a landfill.”
Green’s own approach? Rake up a portion of her leaves, then apply it as a layer of mulch in the pollinator-friendly garden next to her home. The leaf layer acts as a fertilizer that also helps the soil retain moisture and can even mitigate the emergence of weeds when winter abates, she said.
Sacrificing some short-term tidiness can thus yield long-term gains, Green said, that reveal themselves come spring.
“People want pollinators, but they don’t (necessarily) understand that if they clean up their lawn and garden too much in the fall, then they’re moving all those bugs out,” she said. “Sometimes, just holding off, leaving it a little messy, can make it a lot more of a beautiful place in the long run.”