Assessing targets for the restoration of herbaceous vegetation in Ponderosa pine forests

A restoration project is considered a success when the initial target is met, but many targets are plausible. We evaluated the success of a restoration project in its 11th year since treatment in a southwestern ponderosa pine-bunchgrass community and the appropriateness of several targets. We measured the responses of (1) total standing crop; (2) standing crop of five functional groups (C₃ and C₄ graminoids, leguminous forbs, and nonleguminous perennial and annual forbs); (3) graminoid community composition; and (4) standing crop of five common graminoid species (Festuca arizonica, Muhlenbergia montana, Elymus elymoides, Carex geophila, and Poa fendleriana). Targets were quantified in remnant grass patches, which provided the standards for these targets, and were assessed in three other forest patch types (pre-settlement tree patches, post-settlement tree patches, and patches where all post-settlement trees were removed). Patches where all post-settlement trees were removed reached target levels for total standing crop, C₃ and C₄ graminoid standing crop, graminoid community composition, and M. montana, E. elymoides, and C. geophila standing crops. Standing crop of legumes and of F. arizonica did not increase over time in any patch type. Targets were not met in pre-settlement patches or in patches where some post-settlement trees were left standing, suggesting that it is unrealistic to expect equal responses across all patch types. If increasing herbaceous standing crop is a major goal, practitioners should create gaps within the pine forest canopy.