County Agent Update

With the warmer weather in the forecast, many ranchers want to put their cattle out to the start of lush green pastures. But it is just the start, deciding when to start grazing can drastically affect your pastureland for years to come. Starting to graze your land too early will reduce plant leaf area that is needed for the photosynthesis process to replace carbohydrates that were depleted during the winter. Grazing early will cause plant vigor to reduce, the stands are thinned, total forage production is lowered and the chance of diseases, insect and weed infestations are increased. Pasture and range land is damaged by grazing too early and it may take several years of complete rest before the stand regains its productivity. Another thing to consider is that starting grazing too late increases forage loss and waste through trampling or reduced palatability. Timing is everything when it comes to grazing, many times ranchers base their grazing schedule on a calendar date. Sometimes this option is reasonable, but in years where springs come yearly or we have snow until May adjusting your start date is important. North Dakota State University Extension Service recommends that grazing readiness be based on the development stage of the most common grass species on the pasture or range. For native and tame grass species, it is recommended that the plant development stage to begin grazing is when the plants have three to four leaves. Grass developed in an orderly and consistent manner, are the major plant organ of interest for grazing. A new leaf becomes visible on a plant after the one preceding it is almost fully developed. Air temperature that a plant needs to accumulate to produce a leaf can be expressed in growing degree days, or GDDs. For any calendar day, the number of GDDs for that day is the average of the hourly minimum and the hourly maximum temperature in the same 24-hour period minus the base temperature. The date to start recording temperatures for calculating GDDs is on the first day after March 15 that the average daily air temperature exceeds 32˚F for five consecutive days. North Dakota State University Extension Service has a publication out; Determining Grazing Readiness for Native and Tame Pasture written by Kevin K. Sedivec, Rangeland Management Specialist. This publication will help ranchers, and range mangers figure out the right time to start grazing.

Along with starting to graze at the proper time, how you graze can be just as important. Developing a system that is correct for the amount of available forage will help you avoid overgrazing or under grazing, utilization is key when it comes to grazing systems. Poor grazing distribution results in a loss of plant and animal production, ranchers want to get the most out of the land they are using. Grazing the same pasture at the same time every year can create unwanted invasive plants and poor forage quality, rotation is important.