Recent losses of perennial cover in a Great Lakes agricultural region

Abstract

Landscape composition is consequential to ecological functions, and in agricultural regions a simple descriptor of composition is whether the growing habit of vegetation is annual or perennial. Annual vegetation includes most of the crop species grown in central North America (e.g., corn, soybeans, cereal grains, canola), and perennial vegetation includes hay and forage crops (e.g., alfalfa) and most non‐crop land covers (e.g., woodlands, grasslands, wetlands). Recent data show that in farmlands perennial cover is converting to annual cover. Using new remotely sensed annual crop layer spatial data for an intensively farmed region (1,700 km2) of the Lake Huron watershed in Southern Ontario, Canada, this paper describes changes in farmland composition and which transitions are occurring, with suggestions for why the changes are occurring. Perennial cover has rapidly been converted to annual cover in the past five years, with working‐lands perennial cover types identified as the most vulnerable to conversion. Other land cover types are relatively static. Implications for agricultural land conservation and stewardship require attention to this rapid change for conservation of soil, water, and biodiversity in the Great Lakes basin.