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trate levels than non-fertilized crops.
• Plant parts closest to the ground contain the highest concentrations of nitrates. Most are in the lower third of the plant.
• With this in mind, Krantz says strip grazing is not recommended.
• "This practice forces the animals to eat all of the plants. Overgrazing is not recommended for the same reason, as cattle will be forced to consume plant parts with the greater levels of nitrates," he said.
• If grazing is the preferred choice for utilization of these high nitrate crops, Krantz says livestock should never be allowed access if they are especially hungry.
• "Hay or other forage should be provided to them prior to turn-out. Producers should only allow the livestock access for a portion of the day to begin with," he said. "This is recommended until the livestock become acclimated to the higher nitrate levels."
• He adds that if the forages are harvested for silage, cutting heights should be adjusted higher, leaving the lower stalk unharvested.
• Although the costs involved with mechanically harvesting high nitrate forages are significant, Krantz says there are livestock safety benefits to this approach.
• "The ensiling process reduces nitrate levels making them much safer for consumption," he said. "However, it is not recommended to green chop these forages and let them heat overnight as this process favors the formation of nitrite which is even more toxic that nitrate." 
• Oats, corn and barley consistently have been documented as crops with the most potential to account for nitrate poisoning in livestock; however, Krantz says that annual forages such as sudangrass, sorghum-sudan hybrids and millets can be dangerous as well.
• "Weather conditions may intensify the accumulation of nitrates in forages. Plants that survive an extended period of drought will experience increased levels of nitrates immediately following a rain as the parts of the plants begin to resume their growth. The nitrate levels will continue to increase for several days afterward," he said.
• Quick nitrate testing is available at all SDSU Extension Regional Centers
• Suspected crops may be brought to SDSU Extension Regional Centers for a preliminary test that only takes a few minutes. Although exact nitrate levels cannot be determined through this procedure, their presence can be determined. If and when nitrates are verified in the plant tissue, samples are then sent to a lab for further testing.
• "If nitrates are not found, producers can be confident that the forage is safe for

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