It’s January, and we’ve already seen a variety of winter conditions. In all reality, we still have 2 months left of this mystery tour. We’ve seen snow, freezing cold temps, melting, runoff, ice, rain, fog and mud. Personally, as the mom of two young boys, I hope that the mud quickly freezes and goes away. Winter is my only reprieve from it!
In a recent conversation with a participating farmer, he explained that after assessing the conditions he thinks the runoff risks are higher this year than they have been in the past few years. And he’s right. This year presents us with a challenging runoff picture because of the winter conditions and the wet fall leading into winter. So what weather will we receive next and how can you navigate this risky time to avoid nutrient losses?
Scenario #1: Little snow, bitter cold = ice crusting and concrete frost
Normally when the soil freezes in Wisconsin and Minnesota there are some pores (air pockets in the soil) unfilled with water so there is potential for infiltration from a slow or gradual melt, albeit limited. This year, with a wet fall and several melt/thaw/rain cycles already, the soil is already saturated. If the soil surface freezes again, an ice crust will form on the surface. This ice crust will prohibit infiltration and greatly increase the risk of runoff during any future melts.
Scenario #2: More snow, moderate temperatures = a muddy mess
When there is persistent mud, it means that soil is persistently saturated. Persistently saturated soil means a high risk for runoff with any melt or rain event. Not to mention the problems mud causes with getting in the field, including issues with ruts and compaction (and extra laundry from muddy little boys).
Scenario #3: Rain on top of snow or ice covered soils = risky
We’ve already had several rain events, which makes this scenario seem a likely reality. Unfortunately, it is also one of the riskiest when combined with a winter manure application. It is so risky because rain on snow or ice covered soils means no infiltration plus added water into an already saturated system.
The bad news: No matter the scenario, runoff risk is high for the next several months.
The good news: You can control nutrient application timing and placement to minimize the nutrients in runoff.
Discovery Farms data show that manure applied shortly before a runoff event dramatically increases the risk for nutrient loss. Take proper precautions to avoid manure runoff events during a winter like this one:
Avoid manure applications where possible. This isn’t possible for everyone, but for those who do have this option, use it this winter.
Work with your local advisors (County, NRCS, or Extension staff) to identify the safest areas on your farm for stacking or spreading if you must move manure through the rest of the winter
In Wisconsin, use the Runoff Risk Advisory Forecast (http://www.manureadvisorysystem.wi.gov/app/runoffrisk) to assess the runoff risk over the next 10 days. Manure applied within a week of runoff will increase your risk of nutrient loss. Manure runoff events that result in fish kill events are also a risk when manure is applied shortly before winter runoff because ammonia in manure does not quickly convert to other nitrogen forms with cold soil and air temperatures.
I hope that putting out this precautionary message will encourage the weather to straighten up and prove me wrong. To me, that farmer’s assessment of conditions and our conversation that followed is Discovery Farms information hard at work—understanding runoff conditions and assessing risk on a continual basis. Looking for more conversations like this one? Join The WaterWay Network.
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