In this study, soil characteristics after a lightning-initiated fire were evaluated. Following the fire in July 1998, 25 experimental plots were established on the eastern edge of MacKenzie Flats at the Sevilleta National Wildlife Refuge. Ten of these plots were located in a Bouteloua gracilis (blue grama)-dominated site, while 15 were established in another area dominated by Bouteloua eriopoda (black grama).
Disturbance from fire can affect the abundance and distribution of shrubs and grasses in arid ecosystems. In particular, fire may increase grass and forb production while hindering shrub encroachment. Therefore, prescribed fires are a common management tool for maintaining grassland habitats in the southwest. However, Bouteloua eriopoda (black grama), a dominant species in Chihuahuan Desert grassland, is highly susceptible to fire resulting in death followed by slow recovery rates. A prescribed fire on the Sevilleta National Wildlife refuge in central New Mexico in 2003 provided the opportunity to study the effects of infrequent fires on shrub invasion in this region. This study was conducted along a transition zone where creosote bushes (Larrea tridentata) are encroaching on a black grama grassland.
To study the effects of infrequent fires on shrub invasion in Chihuahuan desert grassland.
Contact Burt Pendleton at the email address below for the methods/protocol for this study.
Plots are a replicate and treatment from the previous study. The following codes define the plots listed in this study: 3 B-O and 4 B-O=burned open, 3 B-F and 4 B-F=burned fenced, 3 C-F and 4 C-F=control fenced, 3 C-O and 4 C-O=control open
Quads are 3m by 4m and values range from 3099-3191.
***2003 data were collected before the prescribed fire. All data from subsequent years were collected after the fire.
Data were visually assessed for obvious errors.
In 2003, the U.S. Fish and Wildlife Service conducted a prescribed burn over a large part of the northeastern corner of the Sevilleta National Wildlife Refuge. Following this burn, a study was designed to look at the effect of fire on above-ground net primary productivity (ANPP) (i.e., the change in plant biomass, represented by stems, flowers, fruit and foliage, over time) within three different vegetation types: mixed grass (MG), mixed shrub (MS) and black grama (G). Forty permanent 1m x 1m plots were installed in both burned and unburned (i.e., control) sections of each habitat type. The core black grama site included in SEV129 is used as a G control site for analyses and does not appear in this dataset. The MG control site caught fire unexpectedly in the fall of 2009 and some plots were subsequently moved to the south. For details of how the fire affected plot placement, see Methods below. In spring 2010, sampling of plots 16-25 was discontinued at the MG (burned and control) and G (burned treatment only) sites, reducing the number of sampled plots to 30 at each.
To measure ANPP (i.e., the change in plant biomass, represented by stems, flowers, fruit and foliage, over time), the vegetation variables in this dataset, including species composition and the cover and height of individuals, are sampled twice yearly (spring and fall) at each plot. The data from these plots is used to build regressions correlating biomass and volume via weights of select harvested species obtained in SEV157, "Net Primary Productivity (NPP) Weight Data." This biomass data is included in SEV185, "Burn Study Sites Seasonal Biomass and Seasonal and Annual NPP Data."
Collecting the Data:
Net primary production data is collected three times each year, winter, spring, and fall, for all burn sites. Spring measurements are taken in April or May when shrubs and spring annuals have reached peak biomass. Fall measurements are taken in either September or October when summer annuals have reached peak biomass but prior to killing frosts. Winter measurements are taken in February before the onset of spring growth and only creosote is measured.
Vegetation data is collected on a palm top computer. A 1-m2 PVC-frame is placed over the fiberglass stakes that mark the diagonal corners of each quadrat. When measuring cover it is important to stay centered over the vegetation in the quadrat to prevent errors caused by angle of view (parallax). Each PVC-frame is divided into 100 squares with nylon string. The dimensions of each square are 10cm x 10cm and represent 1 percent of the total area.
The cover (area) and height of each individual live (green) vegetative unit that falls within the one square meter quadrat is measured. A vegetative unit consists of an individual size class (as defined by a unique cover and height) of a particular species within a quadrat. Cover is quantified by counting the number of 10cm x 10cm squares filled by each vegetative unit. It is possible to obtain a total percent cover greater than 100% for a given quadrat because vegetative units for different species often overlap.
Niners and plexidecs are additional tools that can help accurately determine the cover a vegetative unit. A niner is a small, hand-held PVC frame that can be used to measure canopies. Like the larger PVC frame it is divided into 10cm x 10cm squares, each square representing 1% of the total cover. However, there are only nine squares within the frame, hence the name “niner.” A plexidec can help determine the cover of vegetative units with covers less than 1%. Plexidecs are clear plastic squares that are held above vegetation. Each plexidec represents a cover of 0.5% and has smaller dimensions etched onto the surface that correspond to 0.01%, 0.05%, 0.1%, and 0.25% cover.
It is extremely important that cover and height measurements remain consistent over time to ensure that regressions based on this data remain valid. Field crew members should calibrate with each other to ensure that observer bias does not influence data collection
Grasses-To determine the cover of a grass clump, envision a perimeter around the central mass or densest portion of the plant, excluding individual long leaves, wispy ends, or more open upper regions of the plant. Live foliage is frequently mixed with dead foliage in grass clumps and this must be kept in mind during measurement as our goal is to measure only plant biomass for the current season. In general, recently dead foliage is yellow and dead foliage is gray. Within reason, try to include only yellow or green portions of the plant in cover measurement while excluding portions of the plant that are gray. This is particularly important for measurements made in the winter when there is little or no green foliage present. In winter, sometimes measurements will be based mainly on yellow foliage. Stoloniferous stems of grasses that are not rooted should be ignored. If a stem is rooted it should be recorded as a separate observation from the parent plant.
Forbs, shrubs and sub-shrubs (non-creosote)-The cover of forbs, shrubs and sub-shrubs is measured as the horizontal area of the plant. If the species is an annual it is acceptable to include the inflorescence in this measurement if it increases cover. If the species is a perennial, do not include the inflorescence as part of the cover measurement. Measure all foliage that was produced during the current season, including any recently dead (yellow) foliage. Avoid measuring gray foliage that died in a previous season.
Cacti-For cacti that consist of a series of pads or jointed stems (Opuntia phaecantha, Opuntia imbricata) measure the length and width of each pad to the nearest centimeter instead of cover and height. Cacti that occur as a dense ball/clump of stems (Opuntia leptocaulis) are measured using the same protocol as shrubs. Pincushion or hedgehog cacti (Escobaria vivipara, Schlerocactus intertextus, Echinocereus fendleri) that occur as single (or clustered) cylindrical stems are measured as a single cover.
Yuccas-Make separate observations for the leaves and caudex (thick basal stem). Break the observations into sections of leaves that are approximately the same height and record the cover as the perimeter around this group of leaf blades. The caudex is measured as a single cover. The thick leaves of yuccas make it difficult to make a cover measurement by centering yourself over the caudex of the plant. The cover of the caudex may be estimated by holding a niner next to it or using a tape measure to measure to approximate the area.
Height is recorded as a whole number in centimeters. All heights are vertical heights but they are not necessarily perpendicular to the ground if the ground is sloping.
Annual grasses and all forbs-Measure the height from the base of the plant to the top of the inflorescence (if present). Otherwise, measure to the top of the green foliage.
Perennial grasses-Measure the height from the base of the plant to the top of the live green foliage. Do not include the inflorescence in the height measurement. The presence of live green foliage may be difficult to see in the winter. Check carefully at the base of the plant for the presence of green foliage. If none is found it may be necessary to pull the leaf sheaths off of several plants outside the quadrat. From this you may be able to make some observations about where green foliage is likely to occur.
Perennial shrub and sub-shrubs (non-creosote)-Measure the height from the base of the green foliage to the top of the green foliage, ignoring all bare stems. Do not measure to the ground unless the foliage reaches the ground.
Plants rooted outside but hanging into a quadrat-Do not measure the height from the ground. Measure only the height of the portion of the plant that is within the quadrat.
Creosote Measurements till 2013:
To measure creosote (i.e., Larrea tridenta) break the observations into two categories:
1.) Small, individual clusters of foliage on a branch (i.e., branch systems): Measure the horizontal cover of each live (i.e., green) foliage cluster, ignoring small open spaces (keeping in mind the 15% guideline stated above). Then measure the vertical "height" of each cluster from the top of the foliage to a plane created by extending a line horizontally from the bottom of the foliage. Each individual foliage cluster within a bush is considered a separate observation.
2.) Stems: Measure the length of each stem from the base to the beginning of live (i.e., green) foliage. Calculate the cumulative total of all stem measurements. This value is entered under "height" with the species as "stem" for each quadrat containing creosote. All other variable receive a default entry of "1" for creosote stem measurements.
Do not measure dead stems or areas of dead foliage. If in doubt about whether a stem is alive, scrape the stem with your fingernail and check for the presence of green cambium.
Creosote Measurements 2013 and after:
Each creosote is only measured as one total cover. Each quad that contains creosote will have one cover observation for each creosote canopy in quad.
Recording the Data:
Excel spreadsheets are used for data entry and file names should begin with the overall study (npp), followed by the date (mm.dd.yy) and the initials of the recorder (.abc). Finally, the site abbreviation should be added (i.e., mg, ms, or g). The final format should be as follows: npp_burn.mm.dd.yy.abc.xls. File names should be in lowercase.
August 2009 Burn:
On August 4, 2009, a lightning-initiated fire began on the Sevilleta National Wildlife Refuge. The fire reached the Mixed-Grass Unburned plots on August 5, 2009, consuming them in their entirety. As a result, in the spring of 2010, the Mixed-Grass (MG) unburned plots were moved to a different area within Deep Well, southwest of the Warming site.
Also, on August 4, 2009, some of the webs and quadrats within the unburned Black Grama (G) site were impacted by the fire. Thus, webs 2 and 3 were abandoned and extra plots added to areas within webs 1, 4, and 5 that were not burned. Changes were as follows:
Webs 1, 4, and 5: A plot was added to the northeast to compensate for the loss of all plots at webs 2 and 3.
Web 4: A plot was added to the northwest to compensate for the northern plot, which was burned.
01/13/2011-Burn NPP quad data was QA/QC'd and put in Navicat. Matadata updated and compiled from 2004-2010. The mixed-grass unburned plot was moved to the south after the original plot burned unexpectedly in the fire of August 2009. (JMM) 11/28/2009-Burn NPP quad data was QA/QC'd and put in Navicat. Metadata updated and complied from 2004-2009. Mixed-grass unburned data (Fall 2009) was not collected due to unexpected fire at Sevilleta LTER in Aug 2009. (YX) 01/14/09-Metadata updated and compiled from 2004-2008 data. As of 2007, winter measurements are longer being taken. (YX) 12/20/2008-This data was QAQC'd in MySQL. I checked for duplicates and missing quads. (YX)
Other researchers involved with collecting samples/data: Chandra Tucker (CAT; 04/2014-present), Megan McClung (MAM; 04/2013-present), Stephanie Baker (SRB; 09/2010-present), John Mulhouse (JMM; 08/2010-04/2013), Amaris Swann (ALS; 08/2008-01/2013), Maya Kapoor (MLK; 08/2003-01/2005, 05/2010-03/2011), Terri Koontz (TLK; 02/2000-08/2003, 08/2006-08/2010), Yang Xia (YX; 01/2005-03/2010), Karen Wetherill (KRW; 02/2000-08/2009); Michell Thomey (MLT; 09/2005-08/2008); Seth Munson (SMM; 09/2002-06/2004), Jay McLeod (JRM; 01/2006-08/2006); Caleb Hickman (CRH; 09/2002-11/2004), Charity Hall (CLH; 01/2005-01/2006); Tessa Edelen (MTE, 08/2004-08/2005).Data updated 08/18/15: MOSQ changed to MUSQ3; ARPUP6 changed to ARPU9; SPWR changed to SPPO6; a single entry BOER changed to BOER4.
We evaluated the effects of a lightning-initiated fire on responses of vegetation communities. Following a fire in July 1998, 25 experimental plots were established on the eastern edge of MacKenzie Flats at the Sevilleta National Wildlife Refuge. Ten of these plots were located in a Bouteloua gracilis (blue grama)- dominated site, while 15 were established in another area dominated by Bouteloua eriopoda (black grama). We evaluated basal and aerial cover of all plant species at the community level using a vertical line point intercept method along transects within plots. Sampling was conducted immediately after the fire during the last week of July 1998, and again in September and October of 2001.
Experimental Design - Following a lightning-initiated fire in July 1998, 25 experimental plots were established on the eastern edge of MacKenzie Flats at the Sevilleta National Wildlife Refuge. Ten of these plots were located in a Bouteloua gracilis (blue grama)-dominated site, while 15 were established in another area dominated by Bouteloua eriopoda (black grama). In the former site, five of the 10 plots were established in burned areas, and the others were positioned in unburned grassland vegetation. In the latter site, five plots were placed in burned areas, five were positioned in unburned grasslands, and the five remaining plots were located in an area that contained a mix of burned and unburned patches of grassland vegetation.
Sampling Design - All of the plots in the Bouteloua gracilis-dominated site were 4 m x 16 m. Of the 25 plots where B. eriopoda was more abundant, nine were 4 m x 16 m and 16 were 4 m x 25 m. Regardless of site, all plots were oriented such that the long axis of each was parallel to a topographic gradient running east-west.
We sampled vegetation responses on two separate occasions. An initial sampling was conducted immediately after the fire during the last week of July 1998, and a final sample was conducted in September and October of 2001. During each of the two samples periods, four parallel transects were randomly positioned along the long axis of each plot. In 4 m x 16 m plots, transects were 12 m long, and 125 pins were vertically dropped every 10 cm along each transect. Transects were 25 m long in 4 x 25 m plots, and 125 pins were dropped every 20 cm along each transect.
Field Methods - Along each transect, vegetation community data were collected using the vertical point transect method (Bonham 1989). At each pin drop, all species that intercepted the pin were recorded in the order in which they were encountered from vegetation canopy to ground level. Additionally, we noted if a pin directly hit a plant species, bare ground, or litter.
The metadata and data were provided by Sandra Albro Rutter (email@example.com) and Paul Drewa at Case Western University. These data are not yet available to the public and are presently stored in an Excel file. Note that the last three variables in the attributes list are for the species abbreviations worksheet in the Excel file. The metadata were originally in a Word document. -- KLV
We evaluated the effects of a lightning-initiated fire on resprouting responses of perennial grasses at the population level. Following a fire in July 1998, 25 experimental plots were established on the eastern edge of MacKenzie Flats at the Sevilleta National Wildlife Refuge. Ten of these plots were located in a Bouteloua gracilis (blue grama)-dominated site, while 15 were established in an area dominated by Bouteloua eriopoda (black grama). We evaluated basal cover of perennial grasses in systematically positioned quadrats (subsamples) within plots immediately after the fire (last week of July 1998), and in September-October 2001.
Experimental Design - Following a lightning-initiated fire in July 1998, 25 experimental plots were established on the eastern edge of MacKenzie Flats at the Sevilleta National Wildlife Refuge. Ten of these plots were located in a Bouteloua gracilis (blue grama)-dominated site, and 15 were established in an area dominated by Bouteloua eriopoda (black grama). In the former site, five of the 10 plots were established in burned areas, and the others were positioned in unburned grassland. In the latter study area, five plots were placed in burned areas, five were positioned in unburned grasslands, and the five remaining plots were located in an area that contained a mix of burned and unburned grassland vegetation.
Sampling Design - All of the plots in the Bouteloua gracilis- dominated site were 4 m x 16 m. Of the 25 plots where B. eriopoda was dominant, nine were 4 m x 16 m, and 16 were 4 m x 25 m. Regardless of site, all plots were oriented such that the long axis of each was parallel to a topographic gradient that ran east-west.
We sampled vegetation responses on two separate occasions. An initial sample was conducted immediately after the fire during the last week of July 1998, and a final sample was conducted in September-October of 2001. During each of the two sample periods, we collected data from three permanent 1 m x 1 m quadrats at the two corners and the midpoint along the north side of each plot.
Field Methods - Within each quadrat, all perennial grass clumps were identified to species and two perpendicular measurements of diameter/basal cover taken. (The first measurement was taken across the widest part of the grass clump, and the second measurement was taken perpendicular to the first.) Also, we estimated the proportion of live (i.e., green) foliage associated with each grass clump.
These metadata were supplied by Sandra Albro Rutter (firstname.lastname@example.org) and Paul Drew from Case Western University. The data are presently in an Excel file, not available to the public. The data were originally in a Word document.-- KLV
A natural burn occurred in the Deep Well area of McKenzie Flats in June, 1995, following which studies were initiated to evaluate the effect of fire on plant species composition and the spatial and temporal dynamics of regrowth. The burn area was approximately 24 hectares, forming a swath about 200 m wide from the initial lightning-ignition source. The fire moved in a westward direction from the ignition point, leaving a relatively straight border along the southern boundary and an irregular edge along the northern boundary. The fire was extinguished naturally.
One week after the burn, four 100 m line-intercept transects were established along the southern boundary of the burn. Transects were installed perpendicular to the burn, so that 50 m lay inside the burned area and 50 m outside, in unburned grassland. The first transect (nearest the road) was placed 100 m from the west end of the burn and identified as Transect A. The remaining transects (B,C,D) were located at 200 m intervals from Transect A. Rebar was placed at 0 m, 50 m, and 100 m and these points recorded with a GPS unit.
Initial measurements were made in October, 1995. In subsequent years, measurements have been made in late May and late September to evaluate the response of "cool season" and "warm season" plant species. Another fire occurred on June 24, 2001. This burn only affected the unburned southern end of one transect. A prescribed burn in 2003 did not affect the transects.
Transect Preparation - A 100 m measuring tape was affixed to the 0 meter rebar stake (north) and run to the 100 meter (south) end of each transect. The tape was stretched as tight as possible to get the straightest line. Windy days were avoided to prevent the tape from billowing.
Recording Data - Four crew members worked independently, each doing a 100 m segment simultaneously. Microcassette recorders and standard microcassettes were used to record data. At each 100 m segment, the following sequence was followed: Each species/substrate encountered along the line and the distance at which that species/substrate crossed the tape was recorded. Starting location only was recorded as the ending point was the starting point of the next species/substrate.
August 2009 Burn - On August 4, 2009, a lightning-initiated fire began on the Sevilleta National Wildlife Refuge. By August 5, 2009, this fire had reached the Deep Well line-intercept transects. While there was some minor patchiness, essentially, the fire burned evenly across the transects.
Aug.1, 2008: Changes to the data: This dataset (SEV084) includes all deep well burn line intercept transect data files. The data in this file has been rigorously QAQCed. All plant codes have been updated to current kartez codes as listed on the USDA Plants Database found at http://plants.usda.gov/ Questionable identifications and obvious mistakes were updated to the best of my (Karen Wetherill) ability. Old codes are maintained in the database and can be obtained by contacting the data manager. Old meta data and individual year data can be found in /export/db/local/htdocs/data/archive/plant/transect/data_oldformat, but this data has NOT been vigorously QAQCed and contains errors. See the Sevilleta data manager for data and metadata in this old format.Missing data: 1995 meter 40-50 for transect C Notes: - Kristin Vanderbilt -Transect D was more patchily burned than the other transects. Where the comment "2001 BURN STARTS HERE" was inserted represents the location of the first burned plant encountered. Other burned plants in this transect are noted with a "BURNED" comment.26 March 2009. Data are no longer stored in the folder:/export/db/local/htdocs/data/archive/plant/transect/data_oldformat. Instead, current and old data files can be found here: /export/db/local/htdocs/data/archive/plant/dwburntransect. Data have been rigorously qa/qced. For years previous to 2000 the variable condition in not a reliable measurement. For 2000 and subsequent seasons and years the condition measurement is consistent. Copied start into original-entry column so that data are formattted the same with two decimal points for year 1995-2004. 1998 data have overlapping measurements. These are currently still being corrected. TK
Principle investigator: 1995-2002: Gosz, Jim; 2003-2008: Collins, Scott; 2009: Koontz, Terri. 2010-Present: Moore, Douglas.
Data Manager: 1995-1997: Taugher, Kimberly; 1998-2001: Vanderbilt, Kristin; 2002-2003: Seth Munson; 2004-2008: Karen Wetherill; 2009: Terri Koontz; 2010-Present: Kristin Vanderbilt.
Field Crew 1995: Geer, Susan; Gosz, Jim; Romero, Ray; 1996: Taugher, Kimberly; Belden, Lisa; Payne, Jennifer; Monteith, Nancy; Newingham, Beth; Oldehoeft, Kim; Sexton, Jason; 1997: Taugher, Kimberly; Campbell, Mariel; Conn, Rachel; Kuehner, John; Helm, Amy; Kendall, John; 1998: Kuehner, John; Frasier, Jason; Korbe, Nicole; Kroll, AJ; Hayes, Betty; Hersch, Erika.
Employee History for 2000 to 2009: Mike Friggens 1999 to September 2001; Karen Wetherill February 7, 2000 to August 2009; Terri Koontz February 2000 to August 2003 August 2006 to August 2010; Shana Penington February 2000 to August 2000; Heather Simpson August 2000 to August 2002; Chris Roberts September 2001 to August 2002; Caleb Hickman September 9, 2002 to November 15, 2004; Seth Munson September 9, 2002 to June 2004; Maya Kapoor August 9, 2003 to January 21, 2005; Tessa Edelen August 15, 2004 to August 15, 2005; Charity Hall January 31, 2005 to January 3, 2006; Yang Xia January 31, 2005 to August 2009; Michell Thomey September 3, 2005 to August 2008; Jay McLeod January 2006 to August 2006; Amaris Swann August 25, 2008 to November 2009; John Mulhouse August 24, 2009 to November 2009.