Studying the Effect of Leaf Litter on Insects Overwintering in Lawns
A project by The Insect Conservation Center at the Farmscape Ecology Program
Our entomology team is excited to announce the Leave the Leaves Project, a new study exploring how leaving leaf litter in lawns affects insect populations. While conservation campaigns have long encouraged homeowners to “leave the leaves” in yards to provide habitat for insects, research has only recently begun to demonstrate leaf litter’s significant positive impacts on beneficial insects such as butterflies, moths, and parasitic wasps. Curious to learn whether we could replicate such findings here in the Hudson Valley, we enrolled 20 homeowners in a study that will compare the insect faunas found in lawns where leaves are removed in the fall to those where they are left untouched through the winter.
In order to take part in the study, participants were required to have lawns with at least one native oak or maple tree, to mow their lawns regularly (at least once per month), and to have not used chemical pesticides, herbicides, and fertilizers on their lawns for at least three years. After we put out a call for participants in August, we received nearly 60 responses from people interested in allowing us to use their property for the study—an overwhelming amount of support for which we are immensely grateful! From those who responded, we selected 20 homeowners to take part in the study, of whom 10 remove leaves from their lawns each fall and 10 leave the leaves.
This autumn, we will install netting over small patches of each lawn included in the study in order to establish areas where leaves are held in place over the winter and areas where leaves are prevented from returning after being removed. Early in the spring of 2026, we will compare the leaf cover in these patches to that of the rest of the lawn and select locations to place emergence traps, a type of insect trap designed to collect insects emerging from the soil or other substrates. These traps will be left in place to collect insects for a few months, during which time we will retrieve, count, and identify the trapped insects in order to compare the abundance and diversity of select beneficial insect groups between locations that did and did not have leaf cover through the winter.
The Leave the Leaves Project is made possible thanks to the support of several generous private donors.
