American sycamore

Ozone injury usually appears as black or purple spots (stipple), yellow or white bleached spots (chlorotic mottle, needle tip burn), or leaf browning (necrosis). Ozone may also cause premature leaf drop (senescence).

Healthy American sycamore Leaf Courtesy, Virginia Tech Forestry Department

American sycamore Tree Courtesy, Dr. Donald D. Davis, Penn State University