Crop Loss

The analysis may compare harvested production and appraised production with historical yields, field acreage, crop condition, production records, and appropriate comparison data. Historical yield evidence can provide useful context, but changes in acreage, irrigation, management, crop variety, or growing conditions should also be considered before treating a prior yield as the expected result. USDA NASS routinely estimates crop acreage, harvested acreage, yield, and production, while USDA APH-based crop-insurance plans also use documented production histories when establishing approved yields.

The expert can compare when symptoms appeared, their pattern across the field, crop-development stage, weather chronology, pest or disease evidence, irrigation and drainage conditions, and management records. For example, a widespread event corresponding closely with a documented freeze or hailstorm may present different spatial and temporal evidence from a progressively developing disease or localized irrigation problem. When diagnosis of a plant pathogen or detailed reconstruction of a weather event is central, Plant Pathology or Meteorology & Weather expertise may also be required.

Useful materials may include field maps, planting and harvest records, historical yields, scale tickets, storage or delivery records, crop-insurance documents, photographs and video, weather information, irrigation records, fertilizer and pesticide applications, scouting reports, pest and disease records, laboratory results, invoices, aerial or satellite imagery, and contemporaneous communications. USDA NASS maintains historical acreage, yield, and production data, which can also provide broader geographic context when appropriate.