DOI: 10.5061/dryad.zs7h44jgv
title: Height and canopy measurements of native shrubs in southern California

description: The drivers of shrubland biomass in the Mediterranean-Climate Region of
 southern California are not well understood. This is an issue for resource
 managers of shrub-dominated landscapes who need to estimate shrub recovery
 post-fire; track and monitor carbon storage and sequestration; and
 determine the tradeoff in restoration goals between prioritizing carbon
 storage and species richness. We collected field data from 143 field plots
 located in 11 fire scars (ranging from 1 to 12 years old) and used Linear
 Mixed Models to assess the contribution of temporal and environmental
 variables, along with post-fire regeneration strategies of shrub species
 to explain patterns of aboveground shrub biomass. We identified four key
 findings: (1) shrub biomass increased with time since last fire and the
 proportion of resprouting species, and decreased with distance to coast
 and solar radiation; (2) species with the ability to resprout (obligate
 resprouter and facultative seeders) contributed greater biomass at all
 post-fire time periods and locations when compared with obligate seeders;
 (3) we found higher average biomass contributed by both obligate seeder
 and obligate resprouter species in plots closer to the coast than interior
 plots; and (4) fourth, we found a significant positive relationship
 between woody shrub richness and biomass. The findings of this study can
 help support natural resource management decision making for
 shrub-dominated landscapes – including estimating biomass recovery
 post-fire, quantifying carbon storage, and setting goals for shrubland
 restoration. This Dryad submission provides the shrubland biomass field
 data.
description: We measured a total of 143 field plots; 51 in July-September 2020
 and 92 in June-August 2021on the Angeles, Los Padres, and San Bernardino
 National Forests.  Fires sampled in 2020 included the Cave, Thomas
 (divided into Thomas East and Thomas West owing to the fire size), White,
 Whittier, Rey, and in 2021 we sampled the Lake, Thomas West, Rey, Sand,
 White, Powerhouse, Jesusita, La Brea, and Station fires.  The time since
 last fire ranged from 1-12 years. Plots consisted of a
 30 m x 3 m transect (90 m<sup>2</sup>) to allow data to be
 cross-referenced to Landsat imagery, and were located perpendicular to the
 slope. Plot locations were stratified pre-field work using available
 spatial data relating to: (1) National Forest lands; (2) mixed chaparral
 vegetation type which was pre-determined using GIS data (FRAP 2015) and
 confirmed in the field; (3) only burned once in 40 years (USDA 2021); and
 (4) burned with high burn severity using USDA Forest Service’s Rapid
 Assessment of Vegetation Condition after Wildfire (RAVG) data for specific
 fires. We also used high resolution aerial imagery available in Google
 Earth to ensure that candidate plots were not affected by roads, trails,
 excessive herbivory, and were homogenous, i.e. were not bisected by a
 riparian area, landslide, or large exposed rock.  We sought to distribute
 the plots to achieve adequate representation of all stand ages as
 determined by the time since fire. Finally, field crews could modify the
 location of a field plot if it did not meet the composition (homogenous
 mixed chaparral) or disturbance criteria described above. 
 The modified plot location was recorded using a GPS receiver and
 added to the database of plots. We prioritized measuring the variation
 within a single shrub type (mixed chaparral), since it was the most
 extensive of all shrub types in the ecoregion and because we did not have
 adequate representation of the other common chaparral types (e.g.,
 chamise-redshank chaparral and coastal sage scrub) within our sample
 space. Within the 90 m<sup>2</sup>
 monitoring plot, measurements of larger shrubs (&gt;0.5 m in height)
 included: species identity; canopy width (a single measurement where the
 canopy was symmetrical or two perpendicular measurements which were
 averaged where asymmetrical); and height (central base of the shrub
 downslope to the tallest part of the shrub). For small shrubs or seedlings
 (&lt;0.5 m in height), we counted the number of individuals in the
 plot and measured the height and canopy width of the first three
 individuals identified from each species. We assigned shrub species to one
 of three post-fire regeneration strategies: obligate resprouting species
 (OR), obligate seeding species (OS) and facultative seeding species (FS)
 using available literature (Gordon and White 1994, Borchert et al. 2004,
 CNPS 2021, FEIS 2021).
 <strong>REFERENCES</strong>
 Borchert, M., A. Lopez, C. Bauer, and T. Knowd. 2004. Field Guide
 to Coastal Sage Scrub and Chaparral Alliances of Los Padres National
 Forest.” USDA Forest Service Region 5, Ecological Field Guide
 CNPS (California Native Plant Society). (2021). A Manual of
 California Vegetation, online edition. Sacramento, CA: California Native
 Plant Society http://www.cnps.org/cnps/vegetation/ FEIS (Fire Effects Information System). https://www.feis-crs.org/feis/ Flint, L. E., A. L. Flint, J. H. Thorne, and R. Boynton. 2013. Fine-scale hydrologic modeling for regional landscape applications: the California Basin Characterization Model development and performance. Ecological Processes 2:25. Gordon, H., and T. C. White. 1994. Ecological Guide to Southern California Chaparral Plant series. Transverse and Peninsular Ranges: Angeles, Cleveland, and San Bernardino National Forests. Report R5-ECOL-TF-005. Albany WA: USDA Forest Service Pacific Southwest Region. USDA [US Department of Agriculture]. 2021. Fire-return interval departure (FRID) geodatabase, calendar year 2021. http://www.fs.usda.gov/detail/r5/landmanagement/gis/?cid=STELPRDB5327836
description: # Height and canopy measurements of native shrubs in southern California
 ## Description of the Data and file structure This dataset consists of a
 single Microsoft Excel file (named: SoCal_Biomass.xls) reporting
 measurements for 143 vegetation plots measured in Southern California in
 2020 and 2021. Measurements include: • Species = first 3 letters of genus
 and first 3 letters of species (see list below) • LH_code = Life History
 code, OS = obligate seeder, OR = obligate resprouter, F = facultative
 seeder • Height (m) = height in meters • Canopy 1 (m) = 1st measurement of
 canopy (meters) • Canopy 2 (m) = 2nd measurement of canopy (meters),
 perpendicular to Canopy 1 measurement • Cover (%) = % cover of the
 individual in the plot • Dead (%) = % dead material on individual •
 Age_class = adult (=&gt;0.5 m) or young (&lt;0.5 m) • Count = number of
 young individuals • Height 1 = measurement of 1st representative young
 individual • Height 2= measurement of 2nd representative young individual
 • Height 3= measurement of 3rd representative young individual • Diameter
 1 (1) = measurement of 1st representative young individual • Diameter 1
 (2) = measurement of 1st representative young individual, perpendicular to
 Diameter 1 (1) measurement • Diameter 2 (1) = measurement of 2nd
 representative young individual • Diameter 2 (2) = measurement of 2nd
 representative young individual, perpendicular to Diameter 1 (1)
 measurement • Diameter 3 (1) = measurement of 3rd representative young
 individual • Diameter 3 (2) = measurement of 3rd representative young
 individual, perpendicular to Diameter 1 (1) measurement • UTM Zone = UTM
 zone • Easting (Begin) = easting coordinate for beginning of transect •
 Northing (Begin) = northing coordinate for beginning of transect • Easting
 (Middle) = easting coordinate for middle of transect • Northing (Middle) =
 northing coordinate for middle of transect • Easting (End) = easting
 coordinate for end of transect • Northing (End) = northing coordinate for
 end of transect A recording of 'NA' in the xls cells indicates
 no data. The size of the xls file is 3KB These data provide a key input
 into calculating biomass and carbon storage of shrublands in southern
 California and prioritizing post-fire restoration by US Department of
 Agriculture Forest Service resource managers. ## Species codes | Species
 code | Genus | Species | | :----------- | :--------------------- |
 :------------------------------- | | ACMGLA | Acmispon | glaber | | ADEFAS
 | Adenostoma | fasciculatum | | AMOCAL | Arctostaphylos | glandulosa ssp.
 glandulosa | | ARC \* | Arctostaphylos unknown | -- | | ARCGLAG |
 Arctostaphylos | glandulosa ssp. cushingiana | | ARCGLAM | Arctostaphylos
 | glandulosa ssp. mollis | | ARCGLAN | Arctostaphylos | glandulosa | |
 ARCGLAU | Arctostaphylos | glauca | | ARTCAL | Artemisia | californica | |
 BACPLUP | Baccharis | plummerae ssp. plummerae | | BRICAL | Brickellia |
 californica | | CEACRA | Ceanothus | crassifolius | | CEACRAC | Ceanothus
 | crassifolius var. crassifolius | | CEACRAP | Ceanothus | crassifolius
 var. planus | | CEACUN | Ceanothus | cuneatus | | CEALEU | Ceanothus |
 leucodermis | | CEAMEG | Ceanothus | megacarpus | | CEAOLI | Ceanothus |
 oliganthus | | CEAPAU | Ceanothus | pauciflorus | | CEASPI | Ceanothus |
 spinosus | | CERBET | Cercocarpus | betuloides | | CROSCO | Crocanthemum |
 scoparium | | DENRIG | Dendromecon | rigida | | DIP SP. | Diplacus unknown
 | -- | | DIPLON | Diplacus | longiflorus | | ERICON | Eriophyllum |
 confertiflorum | | ERICON? | Eriophyllum | confertiflorum uncertain | |
 ERICPAR | Ericameria | parryi | | ERICRA | Eriodictyon | eriodictyon
 crassifolium | | ERICRAC | Eriodictyon | crassifolium var. crassifolium |
 | ERICRAN | Eriodictyon | crassifolium var. nigrescens | | ERIFAS |
 Eriogonum | fasciculatum | | ERIODICTYON | Eriodictyon unknown | -- | |
 ERIPAR | Eriodictyon | parryi | | ERITRA | Eriodictyon | traskiae | |
 FRACAL | Frangula | californica | | FRADIP | Fraxinus | dipetala | |
 GALANG | Galium | angustifolium | | GALANGA | Galium | angustifolium ssp.
 Angustifolium | | GARFLA | Garrya | flavescens | | GARVEA | Garrya |
 veatchii | | HAZSQU | Hazardia | squarrosa | | HESWHI | Hesperoyucca |
 whipplei | | HETARB | Heteromeles | arbutifolia | | KECBRE | Keckiella |
 breviflora | | KECCOR | Keckiella | cordifolia | | KECTER | Keckiella |
 ternata | | LEPCAL | Lepechinia | calycina | | LONINT | Lonicera |
 interrupta | | LONSUB | Lonicera | subspicata | | LONSUBD | Lonicera |
 subspicata var. denudata | | LONSUBS | Lonicera | subspicata var.
 subspicata | | LUPALB | Lupinus | albifrons | | MALDAV | Malacothamnus |
 davidsonii | | MALFAS | Malacothamnus | fasciculatus | | MALLAU | Malosma
 | laurina | | MALORB | Malacothamnus | orbiculatus | | NONE | No shrubs
 present | -- | | PICMON | Pickeringia | montana | | PRUILI | Prunus |
 ilicifolia | | QUEAGR | Quercus | agrifolia | | QUEBER | Quercus |
 berberidifolia | | QUECHR | Quercus | chrysolepis | | QUEWIS | Quercus |
 wislizeni | | QUEWISF | Quercus | wislizenii var. fructescens | | RHACRO |
 Rhamnus | crocea | | RHAILI | Rhamnus | ilicifolia | | RHUARO | Rhus |
 ovata | | RHUINT | Rhus | integrifolia | | RHUOVA | Rhus | ovata | |
 RIBMAL | Ribes | malvaceum | | RIBQUE | Ribes | quercetorum | | RIBSPE |
 Ribes | speciosum | | SALAPI | Salvia | apiana | | SALLEU | Salvia |
 leucophylla | | SALMEL | Salvia | mellifera | | SAMNIGC | Sambucus | nigra
 ssp. caerulea | | SOLUMB | Solanum | umbelliferum | | SOLXAN | Solanum |
 xantii | | SYMMOL | Symphoricarpos | mollis | | TOXDIV | Toxicodendron |
 diversilobum | | TRILAN | Trichostema | lanatum | | UK CEA | Unknown
 Ceanothus | -- | | UK LONICERA | Unknown Lonicera | -- | | UNKN SHRB |
 Unknown Shrub | -- | | VENCAR | Venegasia | carpesioides | ##
 Sharing/access Information Intended users of this dataset include resource
 managers and researchers who are interested in quantifying shrubland
 biomass post-fire. This dataset is made available under a CC0 license.