DOI: 10.5061/dryad.qrfj6q5vb
title: Data from: A case study of grassland responses to fuel reduction treatment on the mount Hamilton range of California

description: In many grasslands, mowing and grazing are common management methods that
 can decrease fuel loads and alter community composition to achieve
 specific targets, such as increasing diversity or reducing grass
 dominance. Communities may respond with changes in their taxonomic,
 phylogenetic, and functional diversity, species turnover, functional
 shifts, and individualistic species responses. We address these in a 4-yr
 case study of grazing and mowing in a California grassland located in the
 Mount Hamilton Range of Santa Clara County. We hypothesize that both
 grazing and mowing will reduce grass cover and residual dry matter,
 allowing competitive release of a more diverse range of forbs, likely
 increasing functional and phylogenetic diversity. On the other hand, these
 treatments may impose filters on the community (e.g., mowing may eliminate
 tall species), reducing functional diversity and shifting the community
 towards particular functional compositions. In contrast to our
 expectations, grass cover did not respond strongly to either treatment,
 and there were weak effects on residual dry matter. However, there were
 still strong compositional responses. Mowing led to a reduction in tall,
 large-seeded, and perennial species and generally higher functional and
 phylogenetic diversity. The most pronounced response in grazed communities
 was a marked increase in nitrogen-fixing species, paired with reductions
 in functional and phylogenetic diversity. Similar results have been
 observed in previous studies of grazing and mowing impacts at other
 Californiagrasslands sites, providing a basis for predicting species
 responses to these treatments. Both can be useful tools to filter the
 community for particular species compositions, but showed no benefit for
 commonly used restoration targets such as increasing species richness or
 native cover. Continued monitoring of the sites will track potentially
 slow compositional changes and investigate the interactions between
 treatments and interannual weather variation.
description: These data are from grassland vegetation surveys at Blue Oak
 Ranch Reserve, in the Mount Hamilton Range of Santa Clara County,
 California. We surveyed seven sites in the spring of 2021-2024. Each site
 had 3 (or, in one case, 4) transects, with 4 1x1 m sampling plots every
 10m along each transect. Within each plot, we estimated the percent cover
 of each vascular plant. In addition to the resulting
 community matrix, we also provide a variety of plot-level summaries of the
 communities. These include species diversity, functional diversity,
 phylogenetic diversity, and functional structure.
description: # Data from: A case study of grassland responses to fuel reduction
 treatment on the mount Hamilton range of California Dataset DOI:
 [10.5061/dryad.qrfj6q5vb](10.5061/dryad.qrfj6q5vb) ## Description of the
 data and file structure These are 1x1 m vegetation plots collected in May
 of 2021-2024 from Blue Oak Ranch Reserve (part of the University of
 California natural reserve system). We identified all plant species
 growing in each plot and estimated their percent cover. Plots were
 organized along transects within sites (four plots per transect). Two of
 the sites were located in mowed areas, two in areas grazed by cattle and
 two in control areas with neither treatment. Each of these had three
 transects. Additionally, one site (with four transects) was treated with
 herbicides, grazing and mowing. The Community matrix file contains row
 names specifying the sampling event (transect number, plot identifier
 along the transect, year of sampling), then one column for each species
 identified. Taxonomy follows the Jepson Manual.  The Plot summaries file
 provides information on each plot in each year, including its transect
 number, plot identifier, year, and a text string describing the site name.
 The plot coordinates are given by Lat and Long, and the treatment by
 Treatment. Other columns contain computed summaries of the community in
 each plot. These are: shannon: The Shannon diversity of the plot richness:
 The species richness of the plot grass.cover: summed relative abundance of
 grasses native.cover: summed relative abundance of native species
 nfix.cover: summed relative abundance of nitrogen-fixing species
 perennial.cover: summed relative abundance of perennial species MeanSLA:
 the geometric mean of SLA of species in the plot, weighted by their
 relative abundance (m2/kg) MeanHeight, MeanSeed, MeanRootDepth, MeanThick,
 MeanArea, MeanLDMC, MeanNmass, MeanPmass, MeanSRL: As above but for height
 (m), seed mass (mg), maximum rooting depth (m), leaf thickness (mm),
 single leaf area (mm2), leaf dry matter content (proportion), leaf
 nitrogen concentration (mg/g), leaf phosphorous concentration (mg/g) and
 specific root length (m/g) FEve, FDiv, FDis, RaoQ: Measures of functional
 diversity (functional evenness, functional diversity, functional
 dispersion and Rao's quadratic entropy. These are based on three
 traits: SLA, height and seed mass. MPD, MPDSES, MNTD, MNTDSES, PD, PDSES:
 Measures of phylogenetic diversity or structure. MPD is the mean pairwise
 distance between species on the tree, MNTD is the mean nearest neighbor
 distance and PD is the total branch length of the minimum spanning tree
 for the community (Faith's PD). SES versions of each metric are
 richness-standardized. ### Files and variables #### File:
 Plot_summaries_2024.csv **Description:**  ##### Variables * Transect:
 Transect identifier (ranges from 1 to 22) * Plot: Plot identifier along
 each transect (ranges from A to D) * Year: Year of sampling (2021-2024) *
 Site: Text describing the sampling area. Transects from the same site are
 nearby. * shannon: Shannon diversity index of the plot * richness: Species
 richness of the plot * grass.cover: Proportional cover by grasses *
 native.cover: Proportional cover by native species * nfix.cover:
 Proportional cover by nitrogen-fixing species * perennial.cover:
 Proportional cover by perennial species * Lat: Latitude (in decimal
 degrees) * Long: Longitude (in decimal degrees) * Treatment: Treatment
 received by the plot * MeanSLA: The geometric mean of SLA of species
 occurring in a plot, weighted by abundance (m2/kg) * MeanHeight: As above,
 but for height (m) * MeanSeed: As above but for seed mass (mg) *
 MeanRootDepth: As above but for maximum rooting depth (m) * MeanThick: As
 above but for leaf thickness (mm) * MeanArea: As above but for single leaf
 area (mm2) * MeanLDMC: As above but for leaf dry matter content
 (proportion) * MeanNmass: As above but for leaf nitrogen content (mg/g) *
 MeanPmass: As above but for leaf phosphorous content (mg/g) * MeanSRL: As
 above but for specific root length (m/g) * FEve: Functional evenness of
 the community (based on SLA, height and seed mass) * FDiv: Functional
 diversity of the community (based on SLA, height and seed mass) * FDis:
 Functional dispersion of the community (based on SLA, height and seed
 mass) * RaoQ: Rao's quadratic entropy of the community (based on SLA,
 height and seed mass) * MPD: Mean pairwise distance along the phylogeny
 among all species in the plot * MPDSES: MPD standardized against species
 richness * MNTD: Mean nearest neighbor distance along the phylogeny among
 all species in the plot * MNTDSES: MNTD standardized against species
 richness * PD: Faith's PD for the plot * PDSES: PD standardized
 against species richness #### File: Community_matrix_2024.csv
 **Description:**  ##### Variables * Rownames specifying the transect
 number, plot ID and year. * Achillea millefolium: for all species: percent
 cover of that species * Acmispon wrangelianus * Agoseris grandiflora *
 Agoseris heterophyla * Aira caryophyllea * Amsinckia menziesii * Anagallis
 arvensis * Astragalus gambelianus * Avena barbata * Avena fatua * Briza
 minor * Bromus carinatus * Bromus diandrus * Bromus hordeaceus * Bromus
 laevipes * Bromus madritensis * Calystegia collina * Carduus pycnocephalus
 * Castileja attenuata * Centaurea melitensis * Cerastium glomeratum *
 Chlorogalum pomeridianum * Cirsium vulgare * Clarkia purpurea * Crepis
 capillaris * Cynosurus echinatus * Daucus pusillus * Dichelostemma
 capitatum * Elymus glaucus * Elymus triticoides * Erodium botrys * Erodium
 cicutarium * Erythranthe microphylla * Festuca perennis * Galium aparine *
 Geranium dissectum * Geranium molle * Hordeum marinum * Hypochaeris glabra
 * Hypochaeris radicata * Lactuca seriola * Linum bienne * Logfia gallica *
 Lupinus bicolor * Lupinus sp. * Madia gracilis * Medicago polymorpha *
 Melica californica * Microseris douglasii * Plagiobothrys nothofulvus *
 Rumex acetosella * Rumex crispus * Sanicula bipinnatifida * Scandix
 pecten-veneris * Sidalcea malviflora * Sisyrinchium bellum * Sonchus asper
 * Stipa pulchra * Taeniatherum caput-medusae * Taraxacum officinalis *
 Thysanocarpus curvipes * Torilis arvensis * Trifolium albopurpureum *
 Trifolium bifidum * Trifolium dubium * Trifolium glomeratum * Trifolium
 hirtum * Trifolium microcephalum * Trifolium microdon * Trifolium repens:
 * Trifolium sp. * Trifolium subterraneum * Trifolium willdenovii *
 Triphysaria pusilla * Triteleia laxa * Tropidocarpum gracile * Unknown *
 Vicia sativa * Vicia villosa * Viola pedunculata * Vulpia myuros * Wyethia
 angustifolia ## Code/software No special software is needed, but we
 performed all analysis in R. ## Access information Data was derived from
 the following sources: * Plant trait data originated in part from the TRY
 plant trait database: Kattge, J., Bönisch, G., Díaz, S., Lavorel, S.,
 Prentice, I. C., Leadley, P., Tautenhahn, S., & Werner, G. (2020). TRY
 plant trait database - enhanced coverage and open access. Global Change
 Biology, 26(1), 119-188 * The phylogeny was produced using
 V.PhyloMaker2: Jin, Y. and H. Qian. 2022. V. PhyloMaker2: An updated and
 enlarged R package that can generate very large phylogenies for vascular
 plants. Plant Diversity 44: 335-339.