Lab Sampling Procedures

1
Lab Sampling Procedures

• Tom Hahn
• Lakewood MLRA Office
• Soil Scientist Workshop
• March 17-19, 2009

2
MO6 Lab Sampling Guidelines

• See NSSH 631
• MO6 Guidelines are for production soil surveys
  only
• Objective to ensure cost-effective sampling and
  meaningful results, improve quality of soil
  survey

3
Analyses at the Project Office

• CCE, pH run routinely on full pedon descriptions
• Other analyses
• Sieving for sand content
• EC meters
• Hydrometer particle-size distribution

4
Reference Sampling

• Allow staff to plot lines, and describe and
  classify soils with added confidence
• Limited number of analyses, maybe not all
  horizons
• Short turn-around time
• No work plan needed

5
Characterization Sampling

• For important soils and where extensive soil
  property data needed
• Entire pedon sampled
• Standard suite of lab analyses
• Work Plan required
• Scheduled in advance

6
Planning Sample Collection

• Reference samples
• Sample all horizons if more than a few analyses
  requested
• Large scope reference samples
• When number of analyses approaches complete
  characterization
• Must be on approved map units
• Must be modal or representative pedons
• Follow complete characterization protocols

7
Approximate Lab Costs (1996)

• Reference Samples
• Per sample - 50
• Per pedon - 250
• Characterization Samples
• Per sample - 250 350
• Per pedon - 1500 - 2100

8
Identifying numbers for field samples

• YR ST CCC 11 where
• YR two-digit calendar year (not fiscal year)
• ST state FIPS code (e.g. CO, WY)
• CCC three digit county FIPS code (note this
  may not be the same as the soil survey area code)
• 11 two-digit consecutive pedon number (first
  pedon sampled in county in that year is 01, etc.)

9
Procedure for Requesting Lab Analyses

• Characterization
• Requested 1 yr in advance, through NSSC
• Work Plan required well in advance
• Reference
• Requested through MO6 SDQS
• Need pedon in NASIS
• Complete Request form

10
Key NASIS Elements Must be Populated

• Site latitude and longitude coordinates, with
  datum name
• Site Area Overlap (enter overlaps with legend,
  County, MLRA, and mapunit)
• Pedon User Site ID
• Pedon Horizon Sample Field Sample ID (the field
  sample number for the horizon, e.g.
  07WY041001-01) (These numbers do not need to be
  consecutive - if horizons are skipped during
  sampling, there will be a skip in the horizon
  sample numbers)
• DO NOT ENTER Pedon Horizon Sample Lab Sample -
  this is a number assigned by the lab only (such
  as 08N00362)
• Pedon Soil Name As Sampled
• Pedon Taxonomic Class
• Pedon PSC Top Depth
• Pedon PSC Bottom Depth
• DO NOT ENTER Pedon Lab Pedon - this is a
  number assigned by the lab only (such as 08N00560)

11
Request Form
12
Common Physical Analyses

• Code Analysis name Common
  Taxonomic Applications
• DbWR Bulk Density, Clod
  Andic materials
• PSDA PSDA, Air-dry, lt2 mm Particles
  Particle-size families
• special request fine clay Argillic
  horizon
• special request carbonate clay
  Particle-size families
• WR15b Water Retention, 15 Bar,
  Isotic mineralogy,
• Pressure-Plate, lt2mm
  Particle-size if poorly dispersed

13
Common Chemical Analyses

• Code Analysis Name
  Common Taxonomic Applications
• Carb Calcium Carbonate Equivalent, lt2mm Calcic
  horizon calculate Org C
• Carb2 Calcium Carbonate Equivalent,
  2-20mm Carbonatic and gypsic mineralogy
• CEC CEC and Cations, Routine CE
  Activity, base saturation,
• Natric (Exch. Sodium (ESP))
• EC Electrical Conduct. 120, lt2 mm
  Salic horizon
• Gyp2 Gypsum, lt2mm
  Gypsic horizon
• Gyp2_20 Gypsum, 2-20mm
  Gypsic mineralogy
• NZPRe New Zealand Phosphorus Retention Andic
  materials
• Oxal Acid Oxalate Extract Andic
  materials, spodic materials
• pHNaF pH, NaF
  Isotic mineralogy, andic materials
• pHRou pH, Routine
• SatP Saturated Paste and Soluble Salts Natric
  horizon, SAR
• TotC Carbon, Total
  Mollic epipedon, spodic materials,
  Fluventic features