| Abstract: | In North American deserts, grass invasions threaten native vegetation via competition and altered fire regimes. Accurate prediction and successful mitigation of these invasions hinge on estimation of spread rates and their degree of constancy in time and space. We used high-resolution aerial photographs from 11 sites in the Santa Catalina Mountains, southern Arizona to reconstruct the spread of buffelgrass (Pennisetum ciliare), a C4 perennial bunchgrass, since 1980. The total area infested was fit to a logistic model and residuals of the model were compared to climatic factors of the corresponding and lagged time periods. Infestations grew from small colonizing patches in the 1980s to 66 ha in 2008, doubling every 2.26–7.04 years since 1988. Although buffelgrass germination, establishment and distribution are favored by wet summers and warm winters, climate variables did not predict spread rates. Buffelgrass has grown at a constant rate, at least since 1988, when much of its expansion took place. In the study area, minimum requirements are met almost every year for germination and reproduction, establishing a consistent baseline for spread that manifests as a constant spread rate. |
| Genre: | Article |
| ProdID: | 70004664 |
| Citation Author: | Aaryn D. Olsson; Julio L Betancourt; Michael A. Crimmins; Stuart E. Marsh |
| Citation Contributing Office: | Branch of Regional Research Western Region |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 143 |
| Citation Issue: | |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Journal of Arid Environments |
| Citation LatN: | 35.0 |
| Citation LatS: | 27.57 |
| Citation LonE: | -109.92 |
| Citation LonW: | -116.72 |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | 8 p. |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | Elsevier |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Constancy of local spread rates for buffelgrass (Pennisetum ciliare L.) in the Arizona Upland of the Sonoran Desert; 2012; Article; Journal; Journal of Arid Environments; Aaryn D. Olsson; Julio L Betancourt; Michael A. Crimmins; Stuart E. Marsh |
| Citation Start Page: | 136 |
| Citation Volume: | 87 |
| Citation Year: | 2012 |
| Type: | citation/reference |
| Text: | Constancy of local spread rates for buffelgrass (Pennisetum ciliare L.) in the Arizona Upland of the Sonoran Desert; 2012; Article; Journal; Journal of Arid Environments; Aaryn D. Olsson; Julio L Betancourt; Michael A. Crimmins; Stuart E. Marsh |
| URL (DIGITAL OBJECT IDENTIFIER): | http://dx.doi.org/10.1016/j.jaridenv.2012.06.005 |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Sat, 24 Nov 2012 00:00 -0600 |
| Publisher: | Elsevier |
