Remote Sensing Analysis to Quantify Change in Woodland Canopy Cover on the San Carlos Apache Reservation, Arizona, USA (1935 vs. 2017)

Since the late 1800s, pinyon–juniper woodland across western U.S. has increased in density and areal extent encroached into former grassland areas. The San Carlos Apache Tribe wants to gain qualitative quantitative information on historical conditions of their tribal woodlands use as a baseline for restoration efforts. At Reservation, east-central Arizona, large swaths containing varying mixtures juniper (Juniperus spp.), pinyon (Pinus spp.) evergreen oak (Quercus are culturally important focus restoration. To determine changes canopy cover, we developed image analysis techniques monitor tree shrub cover using 1935 2017 aerial imagery compared results over 82-year interval. Results showed substantial increase savannas, encroachment (mostly juniper) grasslands Big Prairie. is currently engaged converting back an open savanna, more characteristic assumed pre-reservation that area. Our shows areas Bee Flat that, under Tribe’s active efforts, have returned levels roughly analogous measured 1935.