A YIELD MODEL FOR USE IN DETERMINING CROP INSURANCE PREMIUMS

The Peace River region of British Columbia is located close to the northern limit of agriculture in Canada. All hazards crop insurance is available for wheat, barley, oats and canola which are grown there. In recent years, increasing claims have indicated that the basis of the insurance needed to be reviewed. Because of the limited amount of data available for the area, the usual methods could not be used. Instead a computer system incorporating a crop growth model has been developed to estimate the 20 year expected losses for wheat and barley from insufficient moisture using local weather and soil data. The system provides regional estimates and maps of risk as well as estimates from individual quarter-section sections of land (1/2 x 1/2 mile2 grid). The crop growth model was calibrated using data from insurance records compiled over a 15 year period near two weather stations in the area. Evaluation was carried out using the method of cross-validation. The prediction standard errors for wheat were 0.34 t ha-1 in the north and 0.26 t ha-1 in the south- For barley, they were 0.21 t ha-1 and 0.31 t ha-1 in the north and south, respectively. The system could be easily adapted to other areas and cereal crops. Further work would be needed to incorporate the risk from other hazards such as hail and poor harvest weather into the system.