The Research, The work took place at Notre Dame’s Environmental Research Center that straddles the border between Michigan’s Western Upper Peninsula and Northeast Wisconsin. The site has forest, bogs and swamps, with red and sugar maples as the dominant hardwoods — a preferred food for deer.Of wolves, deer, maples and wildflowers by Eric Freedman first published on June 16, 2016 Source breaks the results of the research down in the following article:Grey wolves are good for wildflowers like the nodding trillium and the Canada mayflower in the Great Lakes region.They’re also good for young red maples and sugar maples.That’s because white-tailed deer are bad for both wildflowers and maple saplings.And wolves are bad for deer.

Source: Gray wolves in northern Wisconsin are saving the forest  – Wolves of Douglas County Wisconsin