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Extension > Minnesota Crop News > May 2015

Thursday, May 28, 2015

May 28 Alfalfa Harvest Alert Data

By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties, marte011@umn.edu, 320-968-5077 if a local call to Foley or 1-800-964-4929... in cooperation with the Central MN Forage Council and cooperating farmers, agribusinesses and Extension Colleagues.

Here is a link to all the Alfalfa Harvest Alert Scissors-Cut information we have received so far from sampling done on Thursday May 28. There is new data for Stearns, Benton, and Morrison County sites - posted in the evening on May 28.
Click Here: May 28 Alfalfa Harvest Alert Data UPDATE May 29

Tuesday, May 26, 2015

Alfalfa Harvest Alert Info - May 26 2015

By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties, marte011@umn.edu, 320-968-5077 if a local call to Foley or 1-800-964-4929

Here is a link to all the Alfalfa Harvest Alert Scissors-Cut information we have received so far from sampling done on Tuesday May 26. There is new data for 11 of 15 sites.

Friday, May 22, 2015

Seed Purity Standards

There have been some surprises this spring with rye showing up in fields when there was no rye planted previously, at least not intentionally. I figured it would be worthwhile to briefly discuss seed purity standards and control options.

First we have to make a distinction between PVP protected varieties and varieties that are, or are no longer, protected under PVP. If a variety is protected under Title V of the Plant Variety Protection Act, certification of the seed is required. Certification standards for the maximum number of seed of the other crops are 5, 10, and 30 seeds per 10 lbs. of seed for foundation, registered and certified classes of seed, respectively. That is roughly equivalent to 0.004%, 0.008% and 0.024% seed of other crop species in a seed lot of wheat, barley, or oats. The same standards apply to all varieties sold as certified seed - whether PVP protected or not.

Thursday, May 21, 2015

Alfalfa Harvest Alert Info - May 21, 2015


By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties, marte011@umn.edu, 320-968-5077 if a local call to Foley or 1-800-964-4929

UPDATED DOCUMENT Friday May 22 at 5 p.m. (All but 2 Thursday/Friday Data)
Here is a link to all the Alfalfa Harvest Alert Scissors-Cut information we have received so far from sampling done on Thursday May 21: May 21 Alfalfa Harvest Alert Scissors Cut Data

Please let me know if something looks to be in error.

Please note cooperators and sponsors listed in this report, and tell them and cooperating farmers, “Thanks for your efforts with this.”

Please plan and works for a SAFE hay harvest.

Hope you have a meaningful and enjoyable Memorial Day.

On behalf of U of M Extension Colleagues Nathan Winter and Abby Neu, 
and the Central MN Forage Council

Assessing frost injury to soybean: Is there an interaction with soil-applied PPO herbicides?

Jeff Gunsolus, Extension Weed Scientist

As people begin to assess soybean stands following the low temperature conditions of May 19th, questions are coming my way regarding the possible interaction of frost with soil-applied PPO herbicides. Is it possible? My answer is yes. Is it widely prevalent? As I receive more reports from around the state my current answer is, not likely.

An interaction of frost with soil-applied PPO herbicides is possible because cold temperatures slow the rate of emergence of the soybean through the herbicide-treated soil and the soybean is limited in its ability to metabolize the herbicide. However, the crook stage of the soybean plant that is expressing injury symptoms appears to be targeted to soybeans planted in early May (May 2 to 4 are frequently mentioned). Soybeans planted in early May were just cracking from the soil at the time of the low temperature conditions and were vulnerable to freeze damage.

Wednesday, May 20, 2015

May 7 Hay Auction.... AND Alfalfa Harvest Alert Info thru May 20

By Dan Martens, Extension Educator, Stearns-Benton-Morrison Counties, marte011@umn.edu, 320-968-5077 if a local call to Foley or 1-800-964-4929

I am posting information and links to documents with data from

1. May 7 2015 Sauk Centre Hay Auction

2. May 18-19 Alfalfa Harvest Alert Scissors Cut Data

Tuesday, May 19, 2015

Frost injury to soybean

Bruce Potter, IPM Specialist, Phyllis Bongard, Extension Educational Content Development and Communications Specialist, and Seth Naeve, Extension Soybean Agronomist


Figure 1. Minimum and maximum temperatures recorded May 18–19 by NOAA.

Spring frost damage to soybean is relatively rare in Minnesota, as the last average frost dates usually occur before soybeans are normally planted. However, soybean planting and emergence is well ahead of the 5-year average, leaving the crop more vulnerable to early season frost events. Temperatures dropped into the low 30s and upper 20s (F) overnight in the west-central and northwestern parts of the state, likely resulting in some degree of frost injury to emerged soybeans in select areas.

Monday, May 18, 2015

Frost injury to corn: What to expect

Jeff Coulter, Extension Corn Agronomist

This year’s early and dry spring has facilitated some of the earliest corn planting dates of all time in Minnesota. This early start to the growing season should allow the corn crop to pollinate earlier than normal. Early corn planting also allow kernels to fill when days are longer, reduces the risk of injury due to an autumn freeze before crop maturity, and allows increased time for grain dry-down prior to harvest.

Assessing frost injury


Patchy frost is expected across Minnesota tonight and tomorrow morning. Frost damage can occur when air temperatures are in the mid-30s on calm nights, as the lack of wind allows the transfer of heat from air near the ground to the air above, resulting in colder temperatures near the soil surface. In general, frost damage tends to be worse in low areas where cold dense air settles, near field edges where vegetation reduces the potential for heat transfer from the soil to the air above, and in fields where high levels of surface residue coverage limit heat transfer from soil. In addition, fields that were recently row-cultivated prior to cold temperatures are more susceptible to frost injury, as tillage dries the surface soil, thereby reducing the amount of heat and moisture that can be transferred between the soil and air.

Monday, May 4, 2015

Will soil-applied herbicides work in a dry year?

Tom Peters, Extension Sugarbeet Agronomist

Two questions are on farmers minds. First, how long will soil-applied herbicides ‘last’ in the soil if it doesn't rain and second, should a farmer consider using a rotary hoe or drag harrow to incorporate herbicides?

Volatility (evaporation), adsorption, and soil moisture effect soil-applied herbicides. Volatility is the change in herbicide physical state, from a liquid to a gas. Most soil-applied herbicides used by farmers have a medium or low vapor pressure meaning they generally will not volatilize during warm and dry conditions. However, understand that herbicides sprayed on soils will move with blowing soil and these effects may impact efficacy. Adsorption is the attachment of herbicides to soils. Herbicides must be bound to soils or they would easily leach away. Most herbicides are moderately or strongly bound to soils colloids and should not be impacted by our dry conditions.
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