Pasture and Forage Minute: Grazing Stockpiled Grass, Alfalfa Soil Sampling

Soil sample probe

Pasture and Forage Minute: Grazing Stockpiled Grass, Alfalfa Soil Sampling

Grazing Stockpiled Grass During Winter

By Jerry Volesky

Grazing stockpiled winter range or pastures has several benefits. It is much less costly compared to feeding hay. On native range, there is little risk of damage to the grasses because they are dormant and winter stocking rates can be somewhat higher compared to the summer. Oftentimes, you will notice that native pastures only grazed during the winter are the most vigorous and productive.

It is important, however, that you closely monitor body condition of the cows during the winter grazing period. Crude protein is generally the most limiting nutrient during winter grazing. The crude protein content of dormant warm-season grasses will be around 55 to 7% and will slowly decline through the winter months from weathering and as the cattle selectively grazing the higher quality forage in a pasture. 

Stockpiled cool-season grass pastures are those that have been only lightly or not grazed during the growing season. These pastures may have slightly higher crude protein levels, but that quality will also decline as the winter progresses. Feeding the right amount of protein supplement while winter grazing will allow the cows to effectively utilize that winter forage and maintain the desired body condition.  

A possible grazing management strategy that can be used is to do simple rotational grazing where cattle are periodically moved to a new winter pasture. This will allow for a more consistent diet quality when winter grazing.  

Whatever your strategy, consider carefully what kind of nutrition animals are getting from the pasture so you neither underfeed nor overfeed expensive supplements. And be sure to provide salt, calcium, phosphorus and vitamin A free choice at all times.

Winter grazing is a great opportunity to reduce winter feed costs. With proper management, it can help you meet many of your feeding goals.  

Alfalfa Soil Sampling

By Brad Schick

How did alfalfa fields fare this year? Drought, fall armyworms, and now fertilizer prices will affect what management decisions are made. This makes soil sampling this fall even more important.

The fertility of our soils is essential to creating good yields in alfalfa. All alfalfa fields should be sampled, especially for phosphorous, potassium and pH, while sulfur should be checked on sandy and weathered soils. Nitrogen is usually not needed because alfalfa fixes its own.

Soil cores and recommendations are often based on cores taken down to eight inches. However, if historically samples have been at a different depth — such as six inches — stay with the historical and adjust accordingly if recommendations are based on an eight-inch depth. Due to mineralization, soils have more nutrients readily available nearer the soil surface, so deeper sampling depths can dilute the samples and increase nutrient supplement recommendations.

If sampling yourself, make sure the sampling is done in an accurate and precise manner. Soil type, grid or a composite sample of 20 to 40 acres are several ways to take soil samples. With the latter, 10-15 cores will need to be composited to create a more accurate sample.

Precision and accuracy will change by sampling method and is affected by the element being analyzed. For example, phosphorous is accurate but not always precise with the variability across a field. Keep in mind that soil sampling may not reduce the overall cost of fertilizer needed but will help ensure that it is applied to the places in the field more appropriately, which can result in a better yield.

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