Science shows two of Metroparks' more 'contentious' decisions are paying dividends

Oct. 27—Metroparks Toledo now has scientific evidence to prove two of its more controversial decisions in recent years — culling deer and removing non-native trees, including pines — have paid dividends in terms of expanded, diversified, and healthier plant growth.

During a presentation Wednesday to three park commissioners, the results of a one-of-its-kind, three-year study of ecological changes to several parks revealed improvements not only to plant growth between 2018 and 2021, but also a greater abundance of those listed as endangered or threatened.

Park district commissioners Scott Savage, Fritz Byers, and Kevin Dalton heard the extensive presentation by Karen Menard, Metroparks Toledo's research and monitoring supervisor, and Scott Abella, a one-time Metroparks intern who went on to become a University of Nevada-Las Vegas associate professor of restoration ecology and founder of a consulting firm called Natural Resource Conservation, LLC.

The park district's other two commissioners, Lera Doneghy and Molly Luetke, were absent.

Plants have, of course, been studied in parks nationwide for decades.

But this three-year study, which Mr. Abella recommended to the board a few years ago, was the first time geographic information systems technology was used to attempt apples-to-apples comparisons within small, scientifically selected plots of land within several of the Metroparks.

Each plot was a mere 0.12 acre in size, roughly the equivalent of two mid-sized conference rooms — or about twice the size of the new Glass City Metropark Pavilion, the setting for Wednesday's monthly board meeting.

Ms. Menard walked commissioners through the study's parameters, explaining how an intense focus was maintained within each of those plots. Data was collected year-round. Then-and-Now photographs were presented to help illustrate some of the changes.

Some 854 plant species were observed across the collection of land plots, which totaled 17 acres.

Many now teem with new growth. Sixty state-listed rare plants, about 12 percent of Ohio's rare and endangered plant species, were found. More bees and other pollinators were returning to areas to help plants return.

To help put that into perspective, consider that those 17 acres of Metroparks plots contain 91 percent of the number of plant species found at Cuyahoga Valley National Park, and 56 percent of the number of plant species found at Yellowstone National Park.

Interns helped with information, sometimes in rough conditions.

"It's hard to overstate the challenging nature of this work," said Tim Schetter, Metroparks Toledo's natural resources director. "It's a remarkable physical and mental accomplishment to do this."

Dave Zenk, the parks district's executive director, said the results show the district made the right call on what he described as two of its most "contentious" issues with the public in recent years. Spokesman Scott Carpenter confirmed Mr. Zenk was referring to the as-needed deer culls and removal of non-native trees, including mature pines at Oak Openings Metropark.

The pines were planted by the park district decades ago when it contemplated harvesting them to help pay for operations.

Deer populations vary among the parks. But years ago, the district had on average only one deer per square mile of its publicly owned land. Now, the goal is to keep the concentration between 15 and 20 deer per square mile. Deer densities much higher than that affect not only plant growth, but also multiple other forms of insects and wildlife that depend on abundant, healthy plants, Mr. Schetter said.

"What deer do on a landscape has a disproportionate impact, either positive or negative, on other species," he said.

Mr. Abella gave commissioners a historical overview, explaining how there is evidence bison and elk once roamed what is now northwest Ohio long before it became developed.

He also said aerial photographs show many of today's busy corridors in western Lucas County, including Airport Highway, were used for farmland. But many of those farms went bankrupt during the Great Depression and were acquired in the 1930s by what is now Metroparks Toledo.

The bankruptcies gave rise to the creation of the parks district itself that decade, Mr. Schetter agreed after the meeting.

Contributing to those farms' failures, Mr. Abella said during his presentation, were the Oak Openings region's globally rare sandy soils, which made moving farm machinery around extra difficult and costly.

One important plant making a comeback in recent years has been trillium, a favorite of deer because of that plant's high nutritional value, Mr. Abella said.

"These are some of the first to disappear when deer browse," he said.

Deer also browse on oak seedlings. Damage to those young trees has been on a gradual decline since 2015.

It's usually a given there will be some damage. But with a thinner deer herd, this year is the first since 2015 that no district-wide damage to oak seedlings was bad enough to be classified as heavy or severe, according to information Mr. Abella presented.

Since 2015, 43 indicator plants that became a study focus had only 1 percent plant cover. They now have about 10 percent cover, aided in part by more wildflowers, Mr. Abella said.

The rise in pollinators is likely a result of fewer deer eating plants, allowing them to flower, he said.

"Now, there's a much longer flowering season," Mr. Abella said.

In one area in which pines were removed, north of the Oak Openings lodge, the number of plant species rose from 36 in 2018 to 103 in 2021, he said.

Similar gains were found in other plots, at least one achieving a six-fold increase in plants in just three years. At least one had a 13-fold increase in plants over that time.

"Some plots are surrounded by thousands of bees," Mr. Abella said.

The researchers are planning to begin a new, three-year plant study. The next one will focus on plant growth in newer urban parks, such as Middlegrounds Metropark and Manhattan Marsh Metropark, he said.

Several of the findings from the recent study have made their way into scientific papers Mr. Abella and others have published.

First Published October 27, 2021, 1:54pm