Calibration, Application & Documentation

VARS specializes in residue studies.  After study plan approval and site selection, the test substance arrives and is stored in our temperature monitored storage facility.  Application of the pesticide is made after careful calibration of the spray equipment.  Documentation of the calibration procedures, such as nozzle flow rate measurement, is a routine part of the process.  Actual pass times over the treated plots, the actual volumes applied and all environmental conditions are promptly recorded in the field notebook.  Plots are then ready for sampling.                           

callibrating, spraying, measuring spray chemical



collecting samples



RAC (Raw Agricultural Commodity) studies.  It is the responsibility of the pesticide registrant to develop accurate and reliable residue data for their products.  These data determine the magnitude of the residues present in the crop and support the pre-harvest intervals set out on proposed product labels.  The VARS facility is located in Zone 5 (Click here to see Zone 5).  Crop residue sampling is a major focus at VARS and making sure all the proper requirements are met for conducting quality crop residue trials is a priority.  The facility is equipped with a 'Clean' area that is devoted to crop and soil sampling.  This area is separate from the area used for spray equipment and supplies to ensure there is no cross contamination.  Separate equipment including, coolers, water jugs, alcohol, gloves, scales etc. are used for sampling.  


We currently use a hydraulic soil core probe capable of sampling down to 100 cm.  Typically, the top portion of soil is removed with a large diameter probe.  The remaining soil profile is removed using a smaller diameter probe which takes the samples from the same location without touching the soil surface.

The zero contamination sampling method reduces the chance of trace amounts of pesticide reaching the lower soil levels during the sampling procedure.  Soil cores are frozen as soon as possible after sampling, usually within the hour.



soil sample processing

Sample Processing & Shipping
Sample processing is also done at our facility.  Processing of both crop and soil samples can be completed at our facility.  We do what is needed to fulfill the requirements set out by our clients in order to process samples. Samples may then be frozen in our temperature monitored walk-in freezer.

Shipping of frozen samples may take place on dry ice or with a freezer truck delivery service.  Sample lists and chain of custody forms accompany all shipments.  Laboratories and Study Directors are always notified of shipments on the day they leave our facility.





Good Laboratory Practices (GLP) Standards are followed at every stage.  Standard Operating Procedures (SOP) are maintained at our facility, along with the required log books on equipment.  All activities are entered in a raw data field note book prepared for each study.  Archives are maintained for personnel files, log books and raw data.  Quality Assurance (QA) is available by our contract QA unit.



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1909 Maple Manor Road, R.R. #2
Branchton, Ontario, Canada
N0B 1L0

Tel.: (519) 740-8739
Fax.: (519) 740-8857