Fertilizer Application on Frozen or Snow-Covered Ground – A Practice to Avoid

By Mark Fritz, 4R Program Outreach Coordinator

While the chances of frozen soil conditions, as defined to the right, diminish rapidly after mid-February, there are potentially many days in the next month when soil is snow-covered. With many nutrient service providers or fertilizer dealers behind in fertilizer application schedules, the temptation to apply on frozen or snow-covered fields is very real - especially when a customer requests it. Add to that the lack of compaction and the reduction in spring workload and it may begin to look like a viable option. Let’s take a look at the reasons why application on frozen or snow-covered ground is to be avoided.  

The potential for loss or movement

Research, water quality data, and farmer experience in many states - including Ohio - has shown the sharply increased potential for movement of both fertilizer and manure when applied on frozen ground. Commercial fertilizer, especially, is highly soluble and subject to movement. This most often occurs when rainfall occurs after application, before the soil has thawed completely. In the case of snow-covered soils, the quick melt provided by the rain results in a runoff event. We have all observed that our weather has changed; among other things, we have wetter winters, with more frequent and intense rainfall events. Now, more than ever, the potential for loss from frozen or snow-covered applications is very real.

This movement may or may not be off-site. In other words, rather than leaving the field and entering a stream, drainage channel or road ditch, the fertilizer-laden runoff may simply move from a higher point in the field to a lower. While the farmer has not in this case technically lost his investment, it is now in a place where it is not needed. This is especially damaging when the farmer has invested in the added expense of GIS soil sampling and associated VRT application. Those dollars are now essentially wasted, as the distribution of the nutrients in the field has been altered.

Public perception

One of the things that the non-farm public does understand about agriculture and water quality is that applications of nutrients on frozen or snow-covered ground are risky. In fact, their perception has more to do with the time of year (winter) than ground conditions. With the rollout of the H2Ohio program and the associated taxpayer dollars used to fund it, the watchful eye of the public has intensified. In addition, farmer perception is at stake here. While we all can argue that it is legal spread potash on frozen or snow-covered ground, it is certainly not a best management practice, and most farmers know this. We need to be on the cutting edge of the best management practices, not simply looking for loopholes. Potash is, in fact, even more soluble than MAP or DAP, and more subject to movement or loss.

The very real difficulty comes when your farmer customer demands that you apply on frozen or snow-covered ground or else he or she is going down the road to a facility who will apply. Though we don’t want retailers to lose business as a result of this recommendation, we are now in a time when the “powers that be” are letting it be known that we in agriculture are on a very short leash. In other words, if there are not improvements in the way we do things, the hand of heavy regulation will be felt.

We are not saying that water quality problems are due entirely to agriculture! We all know that water quality is VERY complex and that, by and large, we in agriculture have done things well - especially in the last decade or so. However, application of nutrients on frozen or snow-covered ground is simply a “luxury” that we cannot afford.  We need to keep in mind that most of our neighbors have smart phones – NONE of us want to show up on the 5’clock news.