Vegetation inventory, mapping, and characterization report, Saguaro National Park: Volume II, association summaries

Abstract

The Sonoran Desert Network (SODN) conducted a vegetation mapping and characterization effort at the two districts of Saguaro National Park from 2010 to 2018. This project was completed under the National Park Service (NPS) Vegetation Mapping Inventory, which aims to complete baseline mapping and classification inventories at more than 270 NPS units. The vegetation map data were collected to provide park managers with a digital map product that meets national standards of spatial and thematic accuracy, while also placing the vegetation into a regional and national context. A total of 97 distinct vegetation communities were described: 83 exclusively at the Rincon Mountain District, 9 exclusively at the Tucson Mountain District, and 5 occurring in both districts. These communities ranged from low-elevation creosote (Larrea tridentata) shrub-lands spanning broad alluvial fans to mountaintop Douglas fir (Pseudotsuga menziesii) forests on the slopes of Rincon Peak. All 97 communities were described at the association level, each with detailed narratives including lists of species found in each association, their abundance, landscape features, and overall community structural characteristics. Only 15 of the 97 vegetation types were existing “accepted” types within the National Vegetation Classification (NVC). The others are newly described and specific to Saguaro National Park (and will be proposed for formal status within the NVC). This document is Volume II of three volumes comprising the Saguaro National Park Vegetation Mapping Inventory. This volume provides two-page summaries of the 97 associations identified and mapped during the project, and detailed in Volume I. Summaries are presented by district, starting with the Tucson Mountain District. These summaries are abridged versions of the full association descriptions found in Volume III.