Ag Agencies Address Label Restrictions For Crop Rotations

Nov 24, 2014

The following guest article is by Craig Romary, environmental program specialist, and Tim Creger, pesticide program manager, for the Nebraska Department of Agriculture; and Mike Kucera, agronomist, NRCS National Soil Survey Center; Soil Quality and Ecosystems Branch

Once a pesticide is used in a cropping system, the restrictions on the label must be followed for the original crop it is used on, and any succeeding crops, until all restrictions on that label have been met. One of these is called the plant-back restriction. Plant-back restrictions exist for two reasons:

To avoid carryover pesticide injury to the subsequent crop (such as with herbicides).
To protect humans and livestock from elevated levels of pesticide residues that a succeeding crop may accumulate.

Because cover crops are re-emerging as an important practice for conserving soil, increasing soil water, and improving soil health and function, one needs to be aware of these restrictions and include them in the planning process. However, many of the plant species used in today's cover crop mixtures may not be specifically listed on the label to ensure establishment of the stand or the safety of the feed or forage. The following points highlight scenarios that may affect what is planted for cover crops and how they are used. Cover crops serve different purposes than forage crops although they may actually be the same species or mixture. The crop's end purpose — either cover or forage — affects plant-back and forage/harvest restrictions.

Cover crops are planted before or after harvest of the cash crop, where the cover crop will not be grazed or harvested for forage. It is acceptable to plant cover crop species, as long as the pesticide label does not specifically list plant-back restrictions for the cover crop species, or is silent on the cover crop species (not listed on the label). Some pesticide labels will list crop groups rather than specific crop species.

Forage crops are planted before or after harvest of the cash crop, where the crop will be utilized for grazing or as forage for livestock whose meat, milk, or other products will be marketed. If the pesticide label has any of the following, it is an obvious violation of pesticide laws when a prohibited cover species is planted or grazed/harvested for forage within that time:

specific plant-back restrictions for the crop species;
prohibitions against grazing/harvesting forage; or
limits on grazing/harvesting forage within a certain time following a pesticide application.

The absence of any particular forage/cover crop species on the pesticide label does not mean those plant species can be legally grown, harvested, or consumed by animals.

Source:unl.edu

Video: Spring 2026 weather outlook for Wisconsin; What an early-arriving El Niño could mean

Northeast Wisconsin is a small corner of the world, but our weather is still affected by what happens across the globe.

That includes in the equatorial Pacific, where changes between El Niño and La Niña play a role in the weather here -- and boy, have there been some abrupt changes as of late.

El Niño and La Niña are the two phases of what is collectively known as the El Niño Southern Oscillation, or ENSO for short. These are the swings back and forth from unusually warm to unusually cold sea surface temperatures in the Pacific Ocean along the equator.

Since this past September, we have been in a weak La Niña, which means water temperatures near the Eastern Pacific equator have been cooler than usual. That's where we're at right now.

Even last fall, the long-term outlook suggested a return to neutral conditions by spring and potentially El Niño conditions by summer.

But there are some signs this may be happening faster than usual, which could accelerate the onset of El Niño.

Over the last few weeks, unusually strong bursts of westerly winds farther west in the Pacific -- where sea surface temperatures are warmer than average -- have been observed. There is a chance that this could accelerate the warming of those eastern Pacific waters and potentially push us into El Niño sooner than usual.

If we do enter El Nino by spring -- which we'll define as the period of March, April and May -- there are some long-term correlations with our weather here in Northeast Wisconsin.

Looking at a map of anomalously warm weather, most of the upper Great Lakes doesn't show a strong correlation, but in general, the northern tiers of the United States do tend to lean to that direction.

The stronger correlation is with precipitation. El Niño conditions in spring have historically come with a higher risk of very dry weather over that time frame, so this will definitely be a transition we'll have to watch closely as we move out of winter.