Spring Pasture Management - Where do I Start? 

by  Justin Brackenrich and Leanna Duppstadt, Forage and Field Crops Educators with Penn State Extension

Unseasonably warm weather and precipitation have been the common theme of the last several springs. As many of the producers in PA recognize, warmth is a double-edged sword. Warmer means precipitation as rain, rather than snow, and less of the bitter cold feeding and calving conditions we traditionally deal with, but mud has been in no short supply, as we hit the first the beginning of spring.

As the weather warms and the spring rains give us plentiful pasture and hay growth, temptation to get livestock out and onto grass will be high. Wait. If you have the hay and the ability to continue feeding, this will reward you more that turning livestock out on to muddy, underdeveloped pastures.

Soil Fertility

The best place to start when thinking "When will I start grazing?" will be with fertility. Applying fertilizer according to a fall soil test will allow you to make the most economical and environmental decisions for your operation. If you have soil tests and need help interpreting results, start by reading Interpreting Your Soil Test Reports . If you need further assistance, contact your local Penn State Extension Agronomy Educator.

As you start making amendments to your pastures, begin with lime and pH management, as it is one of the most critical steps when managing pastures. Pasture pH management is special and needs to be maintained to ensure optimum growth for grasses and legumes (clovers, birdsfoot trefoil, alfalfa). Lime is usually applied in the fall in perennial forages; however, weather conditions can dictate when applications are made. For more information on pH and liming, read Soil Acidity and Ag Lime .

Lastly, we want to look at nutrient management. Many factors play into pasture nutrient management and optimizing growth, but the one that is most often overlooked are our winter feeding practices. Anytime that feeding happens in pastures, we are providing nutrients to those areas through manure nutrient cycling. In general, 80% of livestock consumed nutrients are redeposited on fields. In respect to hay, this is 40 pounds of potassium, 12 pounds of phosphorus, and 40 pounds of nitrogen per ton of hay fed in field that are returned. This should be considered when making fertilizer purchasing and application decisions.

Pastures and hay can also benefit from an application of supplemental nitrogen at green up to increase plant production. Applying 30-40 pounds of nitrogen per acre can supply a large boost to not only yield and carrying capacity, but also to root growth and plant density. For more information on nitrogen applications, watch our short video on Maximizing Spring Green Up on Pasture. 

Managing Damaged Areas from Winter

At this point you are probably starting to notice a few areas of pasture that incurred some damage over the winter. Most likely those heavy traffic areas near water, feeders, minerals, and their favorite corner of the pasture to hang out. It can be beneficial to have a sacrifice lot during the winter months or even to use during wet weather to save your valuable pastures. But there are usually still some areas post-winter that could use some improvements.

First, if possible, move water, feed and mineral sources to new locations so that you can re-seed the damaged locations or allow them to rest and regrow. Rotating those items more frequently, when possible, or having a permanent location with a concrete pad can help alleviate the stress from heavy traffic. Check out this article, Reducing Pasture Damage During Winter Feeding , to learn more.

Sometimes it is necessary to restore or renovate our main pastures due to excessive damage but it's important to make careful considerations before fully renovating. Your assessment should be based on the current productivity of the pasture and a full-blown renovation should be a last resort. This article, Seeding Perennial Forages: Restoration/Renovation of Pastures and Hay Fields can help you determine your best approach.

Finally, consider what you will plant in your winter-feeding areas or in the damaged spots in your fields. If you are treating areas of your fields or rotating your winter-feeding area, it is best to return them to a suitable perennial forage that fits your operational needs. If you are going to reuse the same feeding area again next winter, consider the use of an annual grass that does not take so long to become established. For more on selecting proper species selection, you can read Selecting the Correct Forage Species or call your local agronomy educator.

Grazing Management

Grazing management is an important aspect of pasture health and productivity. Maintaining good forage heights will ensure that our desirable forages maintain good quality, can suppress weeds, and survive through the summer. Management systems also allow for more even distribution of manure across our pastures. Rotational grazing is when only a section of a pasture is grazed at a time while the remainder of the pasture is left to rest and regrow. A continuous grazing system allows animals to have access to a pasture throughout the entire grazing season.

Continuous grazing systems, while requiring fewer physical inputs from the producer, allows animals to be more selective and graze certain areas and plant species more heavily than others. The forages that are left behind will mature and decline nutritionally as animals continuously return to the new lush growth that was more recently grazed. Rotational grazing favors our desirable forages by limiting the space available for livestock to graze and rotating them to new paddocks, ideally when forages reach a certain height. Then, the paddocks can "rest," which allows for forage to regrow and replenish carbohydrates. This grazing height can be valuable, in terms of botanical compositions, because different forages, both grasses and legumes, will tolerate different grazing heights. In table 1, the start and stop grazing heights are found for different types of grasses and legumes.

Table 1 (seen at left): Start and stop grazing heights for different grass and legume forages. From USDA Pastures for Profit: A Guide to Rotational Grazing

Grazing systems also allow us to manage our carrying capacity, which can help in the spring when pastures are wet. Rotational systems allow us to move animals on and off our pastures to avoid damage. Wet soils allow for hooves to tear through roots, causing damage to forages and potential soil compaction. For more information regarding grazing management on wet soils read, Grazing Management to Avoid Soil Compaction .

Grazing too early in the spring, before forages reach an ideal height, can stunt their growth for the remainder of the grazing season. It's important to remember that what you see above ground in terms of forage biomass is reflected in the soil as root biomass. This is the time when forages are actively growing, accumulating carbohydrates and developing complex root structures. So, if forages are grazed too early, they will not have a good root structure belowground to scavenge for nutrients and water during the summer months. For more information on residue heights, check out Grazing Residue Height Matters .