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Protocol for Building a Modified Whitaker Plot

The Whittaker method utilizes nested plots (plots occurring within other plots like Russian nesting dolls) to statistically survey plant biodiversity in an area of scientific study. This method will generate a species-area curve, a list of recorded plants, plant density estimates, percent cover estimates, and an estimate of the total number of species in the landscape of concern. 

Often, two-or-more plant communities will be compared. Toward this purpose, the Whitaker method will generate a similarity coefficient. 

The original Whitaker plot design utilizes a plot area of 50 meters x 20 meters. The plot protocol below instructs for the making of a 25 meter x 10 meter plot. This scale was useful in the study of active and inactive prairie dog towns which are relatively small. 

To measure the biodiversity of flora using this test, it is not essential to accurately identify all plants at the test site to species; it is only essential to know and keep track of plants that are the same and different from each other. This can be done using temporary field monikers (i.e. mustache grass, etc.). 

Photographs and pressed samples of all plants encountered in the plot need be taken for reference, and to make careful positive identification off-site possible. 

The following protocol is written with the assumption that randomized GPS coordinates have already been generated.

Modified Whitaker.jpeg

Members of the Team

Our study will be limited to three team members; for this reason, organization of tasks is essential to us not burning our heads off in confusion all day long in the hot sun. Responsibilities should be delegated, understood, and kept constant throughout the day. 

Team Supervisor (TS) Responsibilities 

  • To clearly articulate the daily plan.
  • To locate the study area using a GPS unit. 
  • To help build the Whitaker-plot using  meter tape, flags, and stakes.
  • To make on-site identification of plants.
  • To make a summary of daily field work and upload to dropbox after each day of study.

Survey Technician (ST) Responsibilities 

  • To photograph the main plot.
  • To photograph and catalog each subplot. 
  • To take and field press every plant with marks indicating plot/subplot #, date, time, and plant's identifying moniker.
  • To locate the study area using a GPS unit.
  • To build the Whitaker-plot using  meter tape, flags, and stakes.

Field Technician (FT) Responsibilities 

  • To locate the study area using a GPS unit.
  • To help build the Whitaker-plot using  meter tape, flags, and stakes.
  • To keep a log of plant data spoken for each plot/subplot and upload the data to dropbox after each day of study.

Materials

The following materials will need to be brought to the study area.

  1. Compass
  2. A laminated piece of card-stock. 
  3. Dry erase markers.
  4. Data sheets to be used for the day.
  5. Clipboard with attached pen.
  6. The  1 X 0.25 (inside dimensions) 1-10 subplot.
  7. A camera &/or an iPad. 
  8. A small shovel or trowel.
  9. A plant press.
  10. Many newspapers.
  11. Meter stick.
  12. 4 rolls of meter tape.
  13. 1 flag for the center-point.
  14. 4 flags labeled NW, SW, NE, & SE and banded together.
  15. 10 flags labeled 1-10 and banded together.
  16. 4 flags labeled 13NW, 13SW, 13NE, and 13SE and banded together.
  17. 6 flags to be used for plots 11 and 12 banded together.
  18. 10-or-so flags of a different color banded together (to mark plants not previously captured). 
  19. Sturdy stakes.
  20. A rubber mallet.
  21. Bug Spray
  22. Sun Block
  23. Water/snacks

Protocol

Finding the Plot 

  1.  Find GPS coordinate using handheld device.
  2.  Mark center-point with a flag.

Creating the Whitaker Plot

  1. Place the flag through the end of the meter tape at the center point. 
  2. Using a compass, measure 5 meters directly to the south of the center-point. 
  3. Place a temporary flag at this point. 
  4. Retrieve the measuring tape.
  5. Place the temporary flag through the end of the meter tape. 
  6. Using a compass, measure 12.5 meters to the direct west of the flag.
  7. Place the flag labeled SW at this point.
  8. Retrieve the measuring tape.
  9. Remove the temporary flag.
  10. Place the SW flag through the end of the meter tape.
  11. Using a compass, measure 10 m exactly North of the SW flag.
  12. Place a flag labeled NW at this point.
  13. Place a stake at the 1o m/NW flag mark and use it to angle the meter tape.
  14. Using a compass, pull the meter tape 25 m exactly east of the NW flag (this should be the 35 m mark).
  15. Place a flag labeled NE at this point.
  16. Place this meter tape on the ground.
  17. Place the NE flag through the end of a 2nd meter tape.
  18. Using a compass, pull the meter tape 10 m exactly south of the NE flag.
  19. Place a stake at the 1o m/NE flag mark and use it to angle the meter tape.
  20. Using a compass, pull the meter tape 25 m exactly west of the NE flag (this should be the 35 m mark).
  21. This is the SW flag; place 2nd meter tape on the ground. 

Creating Plot 13

  1. Place the flag through the end of the meter tape at the center point. 
  2. Using a compass, measure 5 meters directly to the west of the center-point.
  3. Place a temporary flag at this point. 
  4. Using the compass, measure 1.25 m to the north of the temporary flag.
  5. Place the flag labeled 13NW at this point.
  6. Using the compass, measure 1.25 m to the south of the temporary flag.
  7. Place the flag labeled 13SW at this point.
  8. Pull up the temporary flag.
  9. Place the 13SW flag through the end of the meter tape.
  10. Using a compass, measure 10 m to the east of this flag.
  11. Place the flag labeled 13SE at this point.
  12. Retrieve the measuring tape.
  13. Place the 13SE flag through the end of the meter tape.
  14. Using a compass, measure 2.5 m to the north of 13SE.
  15. Place the flag labeled 13NE at this point.

Creating Sublots 1-10

  1. Starting at the SW flag, place flag #10 three meters to the north (3 meter mark).
  2. Place flag #9 six meters to the north of flag #10 (9 meter mark).
  3. Place flag #8 five meters to the east of the NW flag (15 meter mark).
  4. Place flag #7 six meters to the east of flag #8 (21 meter mark).
  5. Place flag #6 ten meters to the east of flag #7 (31 meter mark).
  6. Place flag #5 four meters to the south of the NE flag (4 meter mark).
  7. Place flag #4 five meters to the south of flag #5 (9 meter mark).
  8. Place flag #3 five meters to the west of the SE flag (15 meter mark).
  9. Place flag #2 six meters to the west of flag #3 (21 meter mark). 
  10. Place flag #1 ten meters to the west of flag #2 (31 meter mark). 

Creating Subplot 11 

  1. Place a flag 1 meter north of the SW flag (1 meter mark). 
  2. Place a flag 2.5 meters to the east of the SW flag (32.5 meter mark).
  3. Place a flag 1 meter north of the flag you just placed at the 32.5 meter mark.

Creating Subplot 12

  1. Place a flag 1 meter south of the NE flag (1 meter mark).
  2. Place a flag 2.5 meters to the west of the NE flag (32.5 meter mark).
  3. Place a flag 1 meter south of the flag you just placed at the 32.5 meter mark. 

Do a little dance; your Modified Whitaker plot is complete. 

Stay tuned for:

How to Perform a Whittaker Survey

&

The Statistical Analysis of Data Gained from the Whittaker Method.

&

Interpreting Biodiversity Data Gained from the Whittaker Method. 

Written by Kevin D. Healey

3/1/2018

 

 

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