@article {JRN55095,
	title = {Plant phenology: Taking the pulse of rangelands},
	journal = {Rangelands},
	volume = {41},
	year = {2019},
	month = {06/2019},
	pages = {129-134},
	chapter = {129},
	abstract = {Plant phenology{\textemdash}the timing of seasonal life cycle events{\textemdash}is a primary control on ecosystem productivity and an integrative indicator of species{\textquoteright} responses to the environment. Plant phenology data can be used to design better management systems by adjusting the timing of grazing, fire and other disturbances relative to the growth stage of key species and in planning restoration activities such as herbicide applications or targeted grazing. Repeated observations needed to understand phenology can be collected at various spatial scales with a variety of methods from field-based observations of individual plants to broad-scale observations of landscape {\textquotedblleft}greenness{\textquotedblright} from satellite imagery. Digital cameras mounted on towers (phenocams) provide a more cost-effective way to collect data to capture vegetation {\textquotedblleft}greenness.{\textquotedblright} Phenocam greenness values are used to generate plant canopy- and community-level metrics in real-time for a fraction of the cost of on-the-ground field observations. Phenocam greenness metrics also serve to link plant- or community-scale phenology observations collected in the field with those from satellite remote sensing and can reveal the plant species or functional groups contributing to satellite NDVI. Phenocam image time series also help interpret rangeland monitoring data by placing data in the context of inter- and intra-annual variability.},
	keywords = {grasslands, invasive species, management tools, monitoring, phenocams, plant phenology},
	doi = {doi.org/10.1016/j.rala.2019.02.001},
	url = {files/bibliography/19-011.pdf},
	author = {Dawn M. Browning and K. A. Snyder and Jeffrey E. Herrick}
}
@conference {50082,
	title = {Does livestock grazing influence spatial patterns of woody plant proliferation?},
	booktitle = {Ecological Society of America Abstracts},
	year = {2009},
	month = {August 2009},
	pages = {COS 127-10},
	abstract = {Patterns of woody plant proliferation in grasslands and savannas influence rates of erosion, spread of disturbance, and nutrient pools.~ Spatial pattern is the outcome of plant dispersal, recruitment, competition/facilitation, and disturbance. We quantified effects of livestock grazing, a widely cited driver of shrub encroachment, on the spatial patterns of velvet mesquite (Prosopis velutina) distribution and recruitment in southeastern Arizona. ~Field surveys of plant canopy size and location spanning 74 years (1932, 1948, and 2006) were conducted on areas grazed by livestock since the late 1800s and on areas protected from livestock since 1932.~ Point pattern analysis and Moran{\textquoteright}s I were used to quantify changes in distribution and spatial autocorrelation over time.},
	keywords = {erosion, grasslands, nutrient, savannas, spatial pattern},
	author = {Dawn M. Browning and Steven R. Archer and Janet Franklin and Guertin, D. P.}
}
@conference {50081,
	title = {Grazing effect on woody plant recruitment in a Sonoran Desert grassland across space and time},
	booktitle = {US International Association for Landscape Ecology},
	year = {2009},
	month = {04/2009},
	publisher = {US, IALE},
	organization = {US, IALE},
	address = {Snowbird, Utah},
	abstract = {<p>Livestock grazing is a commonly cited factor contributing to shrub encroachment in savannas and grasslands. Patterns of woody plant proliferation are known to influence rates of erosion and spread of disturbance and are of practical importance to livestock management with regard to forage distribution and abundance. However, the effects of grazing on woody plant population dynamics and stand structure are poorly understood, owing to a paucity of long-term, spatially-explicit data. We explored the spatial patterns of distribution and recruitment for velvet mesquite (Prosopis velutina) using field surveys spanning 74 years (1932, 1948, and 2006) on areas grazed by livestock since the late 1800s and protected from livestock since 1932. Univariate analyses with Ripley\&rsquo;s K and neighborhood density functions (NDF) revealed mesquite plants were randomly distributed in 1932. In 1948, following 16 years of protection from livestock, plants on the protected area were clustered at all distances (1 to 20m), while mesquite on the grazed area were clustered at short distances (1 to 4m) only. In 2006, mesquite on the protected area remained clustered at all distances, with a marked peak in clustering at short distances (1 to 4m), whereas mesquite on the grazed area were randomly distributed. Bivariate analyses with Ripley\&rsquo;s K and NDF indicated that juvenile mesquite plants (\&lt;1m height) were significantly clustered around adult plants from 2 to 5m on the protected area in 2006; but there were no significant patterns of association between juveniles and adults on the grazed area through time. Previous analyses revealed that spatial autocorrelation in mesquite density did not deviate from random on the grazed area, whereas associations on the protected area became increasingly positive. Grazing influenced recruitment-driven changes in population structure from 1932 to 2006 and protection from livestock facilitated formation of high density shrub clusters and open areas generating high spatial heterogeneity.</p>
},
	keywords = {erosion, grasslands, livestock management, point pattern analysis, proliferation, Santa Rita Experimental Range, savannas, shrub encroachment, spatial ecology, velvet mesquite, woody},
	author = {Dawn M. Browning and Janet Franklin and Steven R. Archer}
}
