Impacts of Leaf Removal from Trails on Trail Condition and Erosion

Abstract

Deciduous tree leaves on recreational trails alter user experience generally making for less enjoyable and possibly more dangerous conditions. Web searches reveal extensive debate regarding the management of leaves on trails with some trail users adamant leaves should be removed and others equally adamant they should not. Despite this debate, there is a dearth of published guidance and empirical research for decisions regarding leaf management on recreational trails. In this study, we experimentally removed leaves from treatment trail segments at Carvins Cove near Roanoke, Virginia, during late fall in 2019 and 2020 and did not remove leaves from control segments. Physical characteristics of treatment and control segments were statistically indistinguishable. Over the following 2-year period, leaf cover on trails, qualitative trail conditions, compressive soil strength, and soil moisture content were measured in winter, spring, and fall. In fall 2021, erosion of trail was also measured. All measured variables were compared between treatment and control segments. Differences in leaf cover of treatment and control segments were detectable through spring, but were undetectable by early fall. During winter, compressive soil strength was lower in leafless segments. Analyses of qualitative data revealed leafless segments as softer and muddier than leaf-covered segments during winter likely due to increased freeze-thaw cycles on trails lacking the insulating layer of leaves. During spring, soil moisture content was lower in leafless segments likely due to the evaporative barrier provided by the leaves on control segments. During spring, compressive soil strength and qualitative condition did not vary among treatment and control segments. No differences in trail conditions were detectable among treatment and control segments during fall. After 2 years, erosion did not vary among treatment and control segments suggesting there is little impact of widespread leaf removal on long-term sustainability of trails. Thus, we recommend decisions regarding leaf removal focus not on efforts to make trails more sustainable, but rather to maximize maintenance resources for desired user experiences. Specifically, trails regularly plagued with mud during freeze-thaw cycles likely benefit from not removing leaves prior to winter as mud is generally among the least desirable of conditions for trail users.