We divided the 24 plots into 11 that were...

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Category: General Publications

Title: Seeding with natives increases species richness in a dry ponderosa pine forest (Arizona).

Author: * Springer, J.D. , * Laughlin, D.C.

Subject: Seeding, Natives, Species richness, Ponderosa pine (Pinus ponderosa)

Abstract: Many restoration practitioners in the southwestern United States have questioned the efficacy of seeding native understory species in regional ponderosa pine (Pinus ponderosa) forests, where limited soil moisture and inopportune precipitation events may prevent many seeds from germinating. Moreover, some researchers and land managers are concerned that seeding could potentially introduce exotics or plants of unknown genetic history. Seeding, however, may provide a supplemental source of propagules in thinned and burned areas that lack mature, seed-dispersing native plants. Sowing native plant seeds on bare mineral soil that is sometimes exposed by prescribed burns may help jump-start revegetation and provide resistance to colonization by non-native species. To better understand the effects of seeding, we compared changes in species richness and composition in 11 seeded and 8 unseeded 0.25-acre (0.1-ha) monitoring plots located in a ponderosa pine-Gambel oak {Quercus gambelii) forest at Grand Canyon-Parashant National Monument (GCPNM) in northwest Arizona. All plots were located in areas that were thinned by fall 1998 and burned in early 1999. Pine trees were thinned from an average density of 75 trees per acre (185 trees /ha) to 18 per acre (46 trees/ha). The seeded plots were evenly spaced throughout nearly 175 acres (71 ha), where, in the summer of 1999, Bureau of Land Management staff had hand broadcast seed at an average rate of 8 lbs of pure live seed per acre (9 kg/ha). The certified weed-free seed mix included native species that were previously inventoried in the study area and were commercially available and affordable. The main management objective was to create a grass-dominated understory that would provide continuous fuels to carry frequent ground fires.

Date: 2004

Type: Journal

Source: Ecological Restoration

Identifier: 22(3):220-221

Publisher: The Board of Regents of the University of Wisconsin System, http://ecologicalrestoration.info/

Format: PDF

Language: English