Solar Meets Sheep (and Bees, and More)

The second word in “solar farm” can sound like a misnomer. Often solar panels sit on former agricultural land, but aren’t what we’d otherwise think of as a farm.

Agrivoltaics aims to change that by hosting PV panels and agriculture on the exact same land. Often, livestock like sheep graze under the solar panels. Sometimes the projects include pollinator habitat as well, which can benefit biodiversity, honey production or adjacent pollinator-dependent crops. And trials are being done growing shaded crops under raised panels, too.

Sheep graze among solar panels in Central New York (Photo: American Solar Grazing Association)

The agrivoltaics concept — also called dual-use solar, or when livestock are involved, solar grazing — is being successfully expanded elsewhere. That includes in our neighborhood of the Northeast (Massachusetts, the Finger Lakes). While it isn’t yet being done at scale in the Hudson Valley, for a range of reasons, interest among farmers and developers is growing.

“When solar’s done right, it can contribute to farm viability. It benefits biodiversity, it benefits pollinators — these larger goals of conservation are coming together,” says Lexie Hain, co-founder of the American Solar Grazing Association. “I’m hopeful this is beginning of a revolution of intelligent co-design.”

The association, formed in rural Ithaca in 2018, has been expanding. Hain has spoken at conferences as nearby as Albany, last January, and as far away (at least virtually) as Europe this fall. She’s aware that land values and terrain are different in the Finger Lakes than near the Hudson River, and that viewsheds are parsed carefully here, too. But she says, “I would love to see it happen in the Hudson Valley. I’m not going to rule it out.”

In some corners of the valley, finding shepherds close enough to a solar project to viably transport sheep from their home farm is the challenge. Nexamp is a developer with community solar arrays in the valley. It currently grazes 2 solar sites in New York State. The advantages to developers like Nexamp can be big: fewer panels damaged by rocks and mowers, reduced vegetation maintenance costs, and more community acceptance.

A sheep arrives to graze a solar site in Central New York (Photo: American Solar Grazing Association)

Next year the company will expand to grazing 12 N.Y. grazing projects, communication manager Keith Hevenor says — but none are local. “For us it’s really about finding the appropriate local farmer who’s willing and able to travel within the distance required,” Hevenor says. “It’s really just a proximity thing.”

Geographic tools have been developed to help it happen. The American Solar Grazing Association recently launched a kind of “matchmaking” tool to help sheep farmers find nearby solar developers, and vice versa.

Scenic Hudson, for its part, is eager to see agrivoltaics emerge as a win-win solution in carefully sited projects. The organization’s Solar Mapping Tool and Renewable Energy Siting Guide provide guidance for bringing it along. “These kinds of techniques can be a real solution and align agricultural policy with renewable energy policy,” says Audrey Friedrichsen, land use and environmental advocacy attorney at Scenic Hudson. “We want to see the transition to renewable energy accelerated with smart planning, because climate change is the issue of our time.”

Despite the delay compared to other areas from North Carolina to Illinois, agricultural observers like Sam Calhoun, FARM Program associate at the Columbia Land Conservancy, believe agrivoltaics is coming our way. The conservancy recently held a Solar Grazing webinar that attracted 25 participants interested in learning what the concept was all about.

“We’re aware of this and looking at it as something we’re going to be seeing more of,” Calhoun says. “We’re trying to stay ahead of it rather than having to play catch-up.”

Lynn Freehill-Maye is managing editor of Scenic Hudson’s HV Viewfinder. She is also a Hudson Valley-based sustainability writer whose work has appeared in the New York Times, the Washington Post, Scientific American, Sierra, Civil Eats, CityLab, Modern Farmer and beyond.

Mowing for Monarchs

Monarch Butterfly

Most homeowners rev up the mower when the grass loses its buzz-cut look. But how does Scenic Hudson decide when to mow the meadows in our parks and preserves? “It’s a balancing act,” says Land Stewardship Coordinator Dan Smith. “Whenever you mow, you’re benefiting something and hurting something else.”

Pollinators on Joe Pye Weed, aka Queen of the Meadow (Photo: Jo-Anne Asuncion)

Mowing cuts back trees and shrubs that, if allowed free rein, could eventually replace the meadow with forest. And it can temporarily suppress the spread of invasive species that crowd out native plants. But mowing also can eliminate the blooming wildflowers and grasses that pollinators like bees and butterflies (including monarchs) rely on for nectar, as well as the winter shelter that other species need.

Deciding when to mow depends on the chief objective. Many of the meadows in our parks are too small to support breeding grassland birds. Still, when possible, Scenic Hudson holds off mowing at least until July 15. “This gives any birds that may be breeding in a field the best chance to fledge their young,” says Smith.

Monarch butterflies on wildflowers from Seed Song Farm (Photo: Matthew Fass)

More often, Scenic Hudson’s meadow management focuses on sustaining habitat and nectar-producing plants for pollinators. “They’re a little less picky about size,” Smith says. To maximize the meadows’ potential for attracting pollinators, mowing is held off even longer, until October 1. “At that point, there are not a lot of nectar sources remaining,” he explains. Likewise, monarchs that have grown from caterpillars to butterflies on our preserves’ milkweed plants “are mostly on their way south,” undertaking their annual migration to Mexico. 

One-third rule of thumb

The general rule of thumb is to mow one-third of a field each year, leaving plenty of nectar for pollinators and coverage for the winter. “But in some of our meadows woody vegetation grows so fast we need to mow more than that to maintain them. It’s one of the things I personally struggle with the most,” Smith says. Adding to his struggle, meadows filled with harmful and especially fast-spreading invasives like black swallow-wort (which closely resembles milkweed but is toxic to monarchs) require monthly mowing.

Monarch caterpillar on common milkweed at Poets’ Walk Park. (Photo: Dan Smith)

In addition to determining when to mow, it’s important to know how much to lop off.  “It’s always good to leave some height,” Smith says. Mowers contracted by Scenic Hudson are advised to leave about 10 inches, which destroys the seed-producing parts of most invasive species while keeping intact many parts of plants where pollinators have laid eggs or larvae may overwinter.   

Smith’s overall assessment of Scenic Hudson’s mowing strategy:  “Our data show it’s working for the most part, but we’re always open to tweaking our approach.”

Solar Buzz

Solar Panels

Underhill solar farm in Poughkeepsie, which went on line in 2019, was one of New York’s first solar arrays developed expressly to include habitat for bees and other pollinator species — a win-win. It not only produces clean energy, weaning us off fossil fuels that contribute to climate change, but supports insects critical for making the valley’s crops — and the region’s agricultural economy — continue to grow. A third of the world’s food depends on pollinators, whose numbers have been declining alarmingly. In the U.S., honeybees alone contribute nearly $20 billion to the value of U.S. crop production, including Hudson Valley food favorites like apples, cherries and blueberries.

(photo courtesy of Clearway Community Solar)