Recently in the Climate and Weather Category

The record breaking temperatures of the past week make it feel more like the middle of May than the middle of March. Obviously, as the fields look ready, the question arises whether this early is too early. With the very late start of 2010 and the disappointing wheat and barley yields that followed still fresh in memory, everyone understands that early planting is paramount. What are the risks of planting too early? Is there such a thing as too early for seeding wheat and other cool season grasses?
Spring wheat (and spring barley and oats) will start germinating in earnest when soil temperatures reach 40⁰F. Once the imbibition phase starts there is no return to dormancy and the germination/emergence should be as quick as possible to establish a healthy, vigorous seedling. Protracted emergence will predispose the seeding to attacks of soilborne fungi like Pythium damping off or common root rot, ultimately reducing stands. Daytime highs in the sixties and night temperatures around 40 are great and will allow the crop to emerge in 8 to 10 days and make for a robust stand.
During this whole germination and seedling emergence and up to the 5-leaf stage, the growing point will be at ~1 inch depth. At this depth it is protected from the ambient temperatures. The crown can sustain temperatures down to 28⁰F and probably even handle short periods of temperatures as low as 22⁰F. Even if above ground leaves freezes, the plant will survive and continue its development as long as the crown does not suffer any freezing injury.

Thus planting this early is a risk if winter returns and temperatures plummet. The immediate forecast, however, looks very favorable for germination and emergence as National Weather Service's extended outlook favors temperatures in the region to average 16-20 ⁰F warmer than normal through the end of March. The 10-day extended outlook looks for daytime highs in the 50 and 60⁰F and nighttime lows in the low 40⁰F or high 30⁰F.

To assess the risk of winter returning in April and the first half of May, I took the weather records from the Northwest Research & Outreach Center that date back all the way to 1890. If we take the latest 30-year climate normal (1981 through 2010), winter can still return in April and when it does, the number of days the minimum temperatures go below 22⁰F between April 1 and May 15 is relatively small at 9% (Table 1). The number of days the nighttime temperatures dips below 28⁰F is much greater at 25%. If however, the warmer weather continues and we look at the 30 warmest Aprils on record, these percentages are cut in half. Taking the warmest 5 April months on record, cuts those percentages again in half. The National Weather Service's outlook for April favors temperatures to average warmer than normal.

Obviously this is somewhat of a roughshod approach as each individual day has its own probability function, meaning that it has its own mean and distribution around that mean. To do these calculations statistically correct you would have to calculate the probability that temperatures dropped below 22, 28 and 32 degrees for each individual day and then average them out over the same time period. Intuitively you would understand that the risk is greatest in early April and diminishes with each day the season progresses.

Bottom line: there is a risk that cold weather returning. Frost is likely to return to the region but the odds of really cold temperatures that could damage the crown appear to be relatively small. Of course, if any snow accompanies the cold weather, the snow will act as insulation and reduce the risk of the crowns freezing.

Learn how conservation tillage can save soil, time, fuel -- and money.

University of Minnesota Extension will host the seventh annual Conservation Tillage Conference and tradeshow Feb. 7 and 8, at the International Event Center in Rochester, MN.

The day-and-a-half-long conference will provide practical, how-to information on nearly every aspect of conservation tillage. Learn how conservation tillage can save soil, time, fuel -- and money. Besides saving valuable soil resources, conservation tillage has been proven to save $25-45/ac in tillage costs. And that's not including your time.

The day-and-a-half-long conference will provide practical, how-to information on nearly every aspect of conservation tillage.

"Whether you are an experienced steward looking to fine-tune what you are doing, a crop consultant who helps growers, or a novice looking to get your feet wet, you should put this conference on your calendar now," says Jodi DeJong-Hughes, Minnesota Extension tillage specialist and conference coordinator.

Experts from the University of Minnesota, neighboring states will present the results of extensive research comparing tillage systems, including strip tillage. In addition, experienced conservation tillage farmers will answer questions and provide management tips.

Conference topics include:

• Precision Ag solutions


• Weed species shift and control


• Nutrient management in high residue systems


• Strip intercropping management


• Soil health with reduced till systems


• Vendor Sessions: Learn about new equipment, cover crops and technology

The popular "Farmer Panel" will be back again, offering practical insights and management tips from experienced northern strip tillers and ridge tillers.

Also back is "Beer & Bull," your chance to pick the brains of other farmers, consultants and researchers in a relaxed, informal setting.

The conference will open with a provocative keynote speech from Robert Recker: "Yield, Profitability, and Sustainability: Where to go from here?" Bob is the owner of Cedar Valley Innovation and a retired John Deere engineer, researching strip intercropping. He studies corn growth on a row by row basis trying to unlock the secrets of using technology and the sun to farm smarter.

The Conservation Tillage Conference runs from 9:00 a.m. to 4:30 p.m. on Tues., Feb. 7th, and from 8:00 a.m. to 12:15 p.m. on Wed., Feb. 8th. The tradeshow will be open both days.

The registration fee is $150 per person, which includes nine continuing education units (CEUs). An early bird fee of $120 per person is offered for those registering by Jan. 25, 2012.

More information, including schedules, maps, contacts and exhibitor registration is available at www.TillageConference.com. Or contact Jodi DeJong-Hughes at 320-815-4112 or dejon003@umn.edu.

By Gary A. Hachfeld, University of Minnesota Extension Educator, Ag Business Management

The early season frost in September caught many of us off guard. Damage to crops varied statewide but the fundamental question is, as a farmer, what should I do regarding a potential loss regarding my federal crop insurance? There are some basic procedures that one needs to follow in the event of a crop loss regardless of cause. This article outlines some of those procedures.

Following an early frost, it is very common for a farmer to utilize a given crop, such as corn, for an alternative use. That is, the corn was insured as grain and intended to be used as grain but due to the early frost, the farmer decides to chop the corn for silage. This could be the case for a number of crops. If this occurs, the farmer must contact their crop insurance agent before they begin to chop the crop for silage, a use other than what was intended. A crop insurance adjuster must evaluate the crop before harvest begins. If the adjuster cannot view the crop in a timely fashion, the farmer can go ahead and chop the field but they must leave a number of check strips for the adjuster to view at a later time. If a farmer decides to use a crop for something other than its intended use, always contact the insurance agent prior to harvest.

Soybean Yield Loss Estimates from Early Frost
Seth Naeve - Extension Soybean Agronomist

Few resources are available to producers and agricultural professionals relative to yield losses from late- season frost injury to soybean plants. A study investigating the risks and benefits of long-season soybean varieties was established in 2008. This work was carried out by the Naeve Soybean Production Project, and was funded by the Minnesota Soybean Research & Promotion Council. While we don't have all of the answers that folks search for after a late-season frost, a small piece of this research effort is described below.

In 2009, 2010, and 2011 soybean plots were established to investigate the yield effects of early frost on a range of soybean maturities. Three varieties with maturities of RM 0.8, 2.0, and 2.8 were examined in 2009. These were planted at a normal seeding date (around May 1) and at a late planting date (around May 21). Frost was simulated with applications of Liberty herbicide at a rate of 32oz per acre in 10 gallons of water on September 7 (early) or September 21 (late). In 2010 and 2011, five varieties ranging from MG 0.8 to 2.8 were planted at a singleplanting date (early May) and treated to simulate frost on three dates (approximately September 7, 14, and 21).

Photo of a soybean plot 'frosted' with Liberty approximately 10 days prior. In the left of the photo is a soybean plot 'frosted' 3 days prior.

By Seth Naeve and Dave Nicolai University of Minnesota Extension

A hard frost occurred early Thursday morning (Sept 15^th) across much of central and southern Minnesota.  The complete effects of this frost or freeze event may not be known for some time.  However, most soybean and corn fields have not reached physiological maturity.  Yield and quality in these fields were likely affected. 

 

By Gary Hachfeld, University of Minnesota Extension
Originally published in Ag News Wire

Farmers who are prevented from planting their crops due to wet spring weather can manage this risk if they have purchased federal crop insurance.

Yield protection, Revenue Protection and Revenue Protection with Harvest Price Exclusion policies all include prevented-planting coverage. There is no prevented-planting coverage with Group Risk Plan or Group Risk Income Protection insurance.

By federal definition, prevented planting is failure to plant the insured crop with the proper equipment by the final planting date designated in the insurance policy. Final planting dates vary by crop and by area. For example, the final planting dates are generally May 31 for corn, June 10 for soybeans, and May 15 to June 5 for wheat, depending on location. Farmers should check with their insurance agent if they have questions on the final planting date.

Farmers who have had an insurance policy in the past are eligible for prevented-planting coverage. New policyholders are also eligible if their loss occurred after the sales closing date and all other prevented-planting requirements are met.

If a farmer is prevented from planting a crop by the final planting date, there are several choices. Those choices include:

1. Plant the crop during the late planting period, which is generally 25 days after the final planting date. There is a reduction per day in coverage using this choice.
2. Plant the crop after the late planting period with no reduction in the insurance coverage.
3. Leave the acreage unplanted and receive a full prevented-planting payment.
4. Plant a cover crop and receive a full prevented-planting payment and graze or hay the crop after November 1.
5. Plant another crop (not the insured crop) after the late planting period or after the final planting date if no late planting period applies. Hay or graze a cover crop, but not before November 1, and receive 35 percent of the prevented-planting guarantee.

There are many provisions included in the prevented-planting provision of federal crop insurance. Keep good records and documentation. When in doubt, read your crop insurance policy or contact your crop insurance agent. Any small infraction of any of the provisions can result in no indemnity payment and loss of the crop insurance protection you purchased.

See more on the late planting page.

By Dave Nicolai and Seth Naeve
Originally published in Ag News Wire

With only 28 percent of corn acres planted prior to May 9 in Minnesota, growers face the difficult decision of when to begin planting soybeans in order to maintain adequate yields.

Soil conditions are of primary importance when considering delayed planting.

Soil conditions and soil temperature

Soil conditions at and after planting usually make a difference in how successfully the crop is established. Soil compaction and smearing is a concern when pulling implements and the planter through, or driving on, wet soil.

To limit soil compaction, keep axle loads under 10 tons and properly maintain air pressure in the tires. Not only does this help the soil, but it will help your tractor run more efficiently and with less slippage. On wet soils, use the lightest tractor that can get the job done.

Soybean has delicate seed, so it benefits when planted about 1 1/2 inches deep, modestly firmed into the seed furrow, covered by relatively loose soil, and into soils with temperatures of 60 to 70 degrees. As of May 9 , soil temperatures at the 2-inch depth averaged 61 and 56 degrees, respectively, at University of Minnesota Research and Outreach centers in Lamberton and Waseca.

The lack of oxygen in saturated soils and the formation of a soil crust of even modest strength can almost eliminate soybean emergence. Therefore, it is important to pay attention to the five-day forecast prior to planting. Planting in cool and wet conditions may lead to poor germination and seedling diseases such as pythium. These problems are magnified by extended cold and rainy periods after planting.

University of Minnesota Extension research indicates that, under ideal conditions, soybeans in southern Minnesota should be planted at about 140,000 live seeds per acre (see Table 1). Soybeans grown in central and northwestern Minnesota require harvest stands of approximately 125,000 to 150,000 plants per acre to maximize yields. This is likely due to shorter-statured soybeans with fewer total nodes that are often produced in these regions. Increased seeding rates are required in central and northwestern Minnesota.

Table 1
Maturity group II soybeans	140,000 live seeds per acre
Maturity group I soybeans	150,000 live seeds per acre
Maturity group 0 soybeans	160,000 live seeds per acre
Maturity group 00 soybeans	170,000 live seeds per acre

Planting date and soybean yield

Since early-May plantings usually result in maximum yields, lower yields should be expected for later plantings (see Table 2). Planting soybeans in Minnesota on May 10 results in only a 2-percent yield loss; on May 15 in a 3-percent yield loss, and on May 20 in a 6-percent yield loss (or 94 percent of normal yield).

Table 2
Planting date	Yield loss (%)	Yield potential (%)
May 1	0	100
May 5	1	99
May 10	2	98
May 15	3	97
May 20	6	94
May 25	9	91
May 30	13	87
June 4	18	82
June 9	24	76
June 14	30	70

For more educational information and tools, visit www.soybeans.umn.edu, a cooperative effort among the University of Minnesota, University of Minnesota Extension, and the Minnesota Soybean Research and Promotion Council. More information about delayed crop planting can be found at www.extension.umn.edu/agriculture/crops/late-planting.

By Daniel Kaiser
Extension Soil Fertility Specialist

With the recent flooding or late season hail there may be questions on whether a credit can be taken from soybeans not harvested for the next year's crop. Soybeans are a high protein crop which means they can contain a large amount of nitrogen. Average vaules of nitrogen removed in soybean grain are reported at around 3.8 lbs of N per bushel (Source IPNI) for a total of 190 lbs of N in a 50 bu/ac soybean crop. In comparison corn grain would remove about 0.90 lbs of N per bushel and a total of 180 lbs of N in a 200 bu/ac crop.  Can all of this nitrogen be counted on if the soybeans cannot be harvested and are plowed under if they cannot be harvested?  

by Mark Seeley, Extension Climatologist

Frost / freeze analyzed maps available

Last weekend (May 8-9) brought widespread overnight frosts and freezes to many parts of Minnesota. Reports indicate that some fruits and crops were damaged, especially in low-lying areas, but many may recover. Further, it appears this may be the last frost occurrence for the season over most of the state, as a significant warming trend is expected to start this weekend.

As is often the case many growers and crop advisors are concerned about assessing any damage due to these low temperatures (primarily 27-32 degrees F), but patience is required. It always takes a few days to sort out which areas might be permanently killed, as many plants, depending on stage of development are resilient and begin regrowth within a week.

The Minnesota Climatology Working Group offers daily analyzed maps to examine the spatial extent of frosts and freezes.

For those interested in storm spotter training

For Minnesota citizens who are interested in becoming storm spotters for the National Weather Service, SKYWARN spotter training classes will be offered free of charge during the month of May on eight different occasions. National Weather Service also encourages citizens to become involved in the eSpotter System which supplements information about storm location, intensity, and aftermath damage assessment. If you are interested in these programs or the free training sessions you can visit the web site.