## Facts

- Wheat farmers contracted with a fertilizer company to sell and apply liquid nitrogen fertilizer on their land, not to exceed 50 pounds per acre.
- The farmers alleged the company applied about 64 pounds per acre and did so in an unhusbandlike manner.
- The farmers claimed the over-application reduced their wheat yield by 10,550 bushels (about 11 bushels per acre), compared to their expected production.
- The farmers offered comparative evidence that neighboring farms used up to 45 pounds per acre and achieved yields of at least 58 bushels per acre, while the farmers’ land averaged 46 bushels per acre that year.
- The company denied over-application and improper application, asserted contributory negligence by the farmers, and claimed the farmers waived any damages claim by paying the full invoice.
- The company introduced expert testimony describing out-of-court experimental tests on nitrogen fertilizer and wheat yields, opining that the amount and manner alleged would not have caused the claimed yield reduction.
- Over objection, the trial court admitted the experimental evidence and submitted waiver to the jury; the jury returned a defense verdict.

## Issues

1. Whether expert testimony and results from out-of-court experiments were inadmissible because the experimental conditions were not shown to be sufficiently similar to the conditions on the farmers’ land.
2. Whether there was sufficient evidence of waiver to submit to the jury the claim that the farmers intentionally relinquished their damages claim by paying the fertilizer bill.

## Decision

- The court held the experimental evidence was properly admitted because the conditions were shown to be substantially similar; differences were for the jury in evaluating weight.
- The court held it was error to submit waiver to the jury because the record lacked evidence from which a reasonable jury could find an intent to waive.
- The judgment for the company was reversed and the case was remanded for a new trial.

## Legal Principles

- Out-of-court experimental evidence is admissible when the proponent shows conditions substantially similar to those at issue; exact identity is not required, and immaterial differences affect weight, not admissibility.
- Trial courts have discretion on admissibility of experimental evidence, with cross-examination and contrary proof addressing dissimilarities.
- Waiver requires an intentional relinquishment of a known right; payment of a disputed amount, without proof of intent to abandon a damages claim (especially when accompanied by assurances of later adjustment), does not establish waiver.

## Conclusion

The court ordered a new trial because, although the fertilizer experiments were admissible under a substantial-similarity standard, the waiver defense should not have been presented to the jury absent evidence that the farmers intended to give up their damages claim by paying the bill.


Foster v. Agri-Chem, Inc., 385 P.2d 184 (Or. 1963)