Rangeland managers and livestock producers are typically optimistic, if we weren’t, we likely would not be in the business of agriculture. We believe things will improve and thus when drought is imminent or even occurring we sometimes wait too long to act. This results in a strain on resources both out on the range and in the pocketbook. Before we can respond to drought we need to come up with a plan on what we will do and tying that plan to critical dates is key for implementation.
In the high, cool season grass dominated plains of Wyoming where I live critical dates are tied to the amount and timing of precipitation we receive in the spring. Grass growth in this area can be directly correlated to the amount of precipitation we receive in March, April, and May. When developing a drought plan rangeland managers and livestock producers who graze on native rangelands should be monitoring precipitation amounts during these three months.
If March is dry, soil moisture will likely be limited. Soil moisture is what drives the initiation of plant growth once temperatures reach optimum. Cool season grasses typically start growth when soil temperature is 40-45 degrees F. If soil moisture is inadequate, growth will be delayed, stunted, or nonexistent depending on future moisture events. Thus the first critical date for a drought management plan is typically April 1. At this time we have a good idea of what snow pack is in the mountains, what the soil moisture is, and we can start monitoring the 10 day forecasts to see what is headed our way. The month of April is critical. Cool season grasses, which provide the bulk of our forage are growing and the correlation between moisture received and peak standing forage in July is high. Therefore the second critical date is May 1. This is where we need to start making some management decisions. If moisture is below what is needed, then its likely time to start looking for other feed or pasture. We may even need to do some destocking depending on the ranch and its resources. The third and final critical date is June 1. At this point the story has been told. Temperatures are rising and cool season grass growth is slowing. Moisture received in June on cool season dominated rangelands will do very little to influence peak standing forage. If your ranch has a higher proportion of warm season grasses, June moisture will be more critical and your story may not be finished. If moisture has not be adequate up to June 1 then management decisions must be made. Most likely livestock numbers will need to be cut and additional forage purchased or leased.
Planning for drought is essential for livestock producers and range managers on all rangelands across the West. In all actuality, drought is more common than wet years. Being prepared and knowing what management decisions will be made during these tough times is essential for sustainability of all resources, including both the rangeland, and the pocketbook.