Repeat photograph of Saguaro National Monument East, Rincon Mountain District, 2010 (color version)

Repeat photograph of Saguaro National Monument (now Saguaro National Park) East, Rincon Mountain District. This photo was taken in 2010 by Dr. Ray Turner, USGS and is a match of a 1935 photograph taken by the National Park Service (NPS). This photo shows the drastic reduction in saguaro (Carnegiea gigantea) populations due to climatic and land use changes since the original 1935 photograph was taken. In 1935, foothills paloverde (Parkinsonia microphylla) and velvet mesquite (Prosopis velutina) trees were scarce since they were harvested during previous decades. After protection of the area by the NPS, those tree species rebounded, as seen in this photograph. Paloverde and mesquite act as 'nurse trees' to young saguaros, providing protection from cold in winters and shade in summer, thereby enabling a stronger chance of saguaro survival during early growth. This photograph is one of a series in the SBSC's Southwest Repeat Photography Collection, stake (camera point) s0013 and is an exact match of a black and white photo in the series.