How to apply slurry under variable field conditions
This is a version of an article written for Progressive Dairy. Read the full version on their website.
Working outdoors will always be unpredictable, and the narrow window of time when applying manure means there is less time to wait for good ground conditions. With heavy equipment and variable field environments, there are steps that can be taken to minimize damage to fields during slurry application.
Minimize compaction
A best practice when doing any work in a field is to minimize the number of passes across the field. Most farmers know to keep to one path through the fields if they need to drive over it. Pulling equipment out of the field should follow the same path taken during setup. In this aspect, dragline application has a clear benefit over manure tanker wagons, as it requires far less passes to be made during application. It also reduces compaction, especially during non-ideal conditions since dragline systems don’t carry the same amount of weight tankers do.
Equipment is larger today than a decade ago, and the bigger tractors have a bigger footprint. To accommodate for this, there have been changes in equipment standards and setups over the years. Floater tires on tractors and hose carts can help minimize compaction and soil disturbance. Front-wheel-assist tractors have transitioned to a preferred four-wheel drive for most operators with three-point hitch attachments for manure injection. Application toolbars are also wider than they once were to help minimize paths over the field. Toolbars used to have a standard of about 16 feet wide, and now most applicators are running 35-foot-wide toolbars. Some custom applicators use pull-type toolbars that range from 40 to 60 feet wide. Making these changes to equipment allows operators to be more versatile in non-ideal field conditions and to extend their application window.
Dragline hose on difficult ground
As drag hose diameters increase from the 5-inch standard of the past to the larger 7- or 8-inch drag hose of today, new hurdles appear. The larger hose is heavier, and it creates more of a rut, field bunching and pulls harder. The softer or muddier the field, the bigger gouge in the field a hose leaves. Larger hose can also pull harder with more tension. Excess bean stubble and cornstalks left over in a field can also contribute to bunching. To combat the creation of a deep groove, applicators can make little curves when going straight to take the hose out of the rut. Additionally, smaller sets can help minimize the hose catching or dragging across wet or compacted ground. Pay attention to your mainline and drag hose and what it is doing to get ahead of any issues.
Potential maintenance to look for
Hard ground can create additional maintenance problems that applicators should be on the lookout for throughout the season. Hose couplers and menders wear out sooner as they are dragged across compacted earth. Replaceable parts on manure injection toolbars may also need to be replaced more often in a tough field. Crews injecting manure in average ground conditions may replace toolbar shoes twice a year, as well as blades when needed. Unyielding fields may see a need for twice the average replacements in a year. These extra replacements can add up in a difficult year. Purchase extra to have on hand ahead of season if sets are on sale or have a special. If you are experiencing hard ground conditions, others likely are as well, and supplies might become limited deeper into the season.
Customer accommodations
Some customers may want manure application done a certain way based on personal preferences. Make sure your crew leader talks with the owner or manager to find out if they want specific things done before and after application, such as a multi-pass completed on end rows. Applications with heavier rates may want end rows worked before and after application to minimize runoff and maximize incorporation. In addition to the weather changing soil conditions, geographical differences can also affect ground conditions and how manure should be applied.
Customers in rocky, sandy or highly erodible land (HEL) may ask for broadcasting or minimal tillage. This can be particularly true in states like Wisconsin, where operators are encouraged to create minimal soil disturbance. However, tillage can help soil compaction and incorporate more nutrients with improved water infiltration. Nitrogen volatilization within the first four days after application is anywhere from 10% to 25% when broadcasting manure. In addition to nutrient loss, you also risk topsoil loss as loosened soils move with wind and water.
Knifing liquid manure into the field results in an average nitrogen volatilization rate of 0% to 2% within four days of application. As the deeper injection of manure spreads below the surface level into the root zone, the manure has a significantly reduced risk of runoff or shedding in rain events. Creating a deeper absorption zone helps to retain liquid and nutrients deeper in the soil, thus giving roots a better chance for a strong hold. Neighbors also benefit from a less noticeable odor of manure.
Application tips
In addition to impressing the customer, it never hurts for your crew to look good for the neighbors. Applying liquid to the ground creates mud, and making mud – especially mud that smells strongly – looks bad, so it’s best to minimize disturbance of the field after application. A good steward of the land will work to minimize manure and nutrient runoff during application. Working the end rows around the field first creates a rapid absorption area. That area acts as a barrier to keep nutrients on the field they were applied to.
Manure application has a limited window of time, and the weather is never guaranteed to provide optimal working conditions. Showing up to a job site prepared with the proper equipment can help maximize your efficiency in the field,. This is true even if the environment is not being cooperative. Understanding what the field is used for can help determine the tillage needed and how much leeway your hose mover has in its maneuvering.
Custom applicators don’t have control of the weather or geographical difficulties, but a little foresight and planning can make the job more efficient. Talk to your Puck sales team member to plan ahead for the next season. Talk with other pumpers from across North America by attending a free, two-day Pump School session. There, you can meet and network with others in the industry.
