Chicago Botanic Garden Fall 2019

If healthy vernal pools can come back, so can frogs Many frogs rely on ephemeral ponds, known as vernal pools, to feed and reproduce. Not only are the spring-to-summer pools im- portant to the frogs, but the frogs eat plant-eating insects and lay eggs, which hatch into tadpoles reliant upon plants to oxygenate the water. It’s a remarkable show- case of how plants and animals work together to maintain a healthy ecosystem. But the equilibrium of this ecosystem is under threat. e invasive shrub buckthorn has degraded vernal pools, sabotaging native wetland plants and inhibiting the growth and develop- ment of chorus frogs, tree frogs, and other environmentally threatened amphibians. the world’s amphibians—are at risk of dying out as a result of climate change, habitat loss, and other anthropogenic effects. Begun in spring 2018 in partnership with the Shedd Aquarium, the study is focused on nine buckthorn-invaded ponds and two healthy pools at Pos- sum Hollow Woods and La Grange Park Woods, Forest Preserves sites tar- geted for volunteer restoration as part of the broader Great Lakes Action Days program. Evans and his thesis adviser, Chicago Botanic Garden conservation scientist Andrea Kramer, Ph.D., who became the Garden’s director of restoration ecology in March, recovered 18 soil samples at a depth of 5 centimeters us- ing simple tools—trowels, rulers, and plastic bags. Seeds culled from these samples were germinated in cold frames at the Garden’s nursery. e at’s why land stewards and research ecologists at several Forest Preserves of Cook County sites are closely tracking a new pilot study being led by Matt Evans, a 27-year-old graduate student in the joint graduate program in plant biology and conservation through Northwestern University and the Chi- cago Botanic Garden. eir hope is that the study will corroborate what Evans suspects: by removing invasive buckthorn from seasonal forest ponds, dormant seeds of native wetland plants will be able to re-emerge on their own and help attract insects and the frogs that feed on them. “One metric of success would be to see higher numbers of chorus frogs,” Evans says. He cites research from the International Union for Conservation of Nature, showing that more than 2,000 species of frogs, toads, and sala- manders—more than 31 percent of