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Degree Days - What A Year It Was, Richard Pope Nov 2010

Degree Days - What A Year It Was, Richard Pope

Integrated Crop Management News

Heat or maybe lack of heat is a better description to use in this recap of the growing season. The degree day departure from average graphic shows how the season progressed by crop reporting district.


Enjoy The Fall Weather –Take A Walk And Collect Some Soil Samples, Gregory L. Tylka Oct 2010

Enjoy The Fall Weather –Take A Walk And Collect Some Soil Samples, Gregory L. Tylka

Integrated Crop Management News

Once harvest is completed, a very productive way to enjoy the fall weather is to collect soil samples for soybean cyst nematode (SCN). In the 1990s and much of the past decade, fall soil sampling for SCN was strongly recommended as a way to scout fields for the presence of this pest. If fields have not yet been tested for SCN, soil samples should be collected for this purpose. But many fields infested with SCN in Iowa likely have already been discovered.


Take Note Of Diseases In A Cool Spring, Xiao-Bing Yang May 2010

Take Note Of Diseases In A Cool Spring, Xiao-Bing Yang

Integrated Crop Management News

Producers in Iowa have had a good planting season. As of Monday, ISU agronomists reported near completion of corn and 50 percent of soybean planted in Iowa. So far this has been one of the most trouble free planting seasons I remember, with some similarities to last season.


Update On Hail Damaged Grain, Charles R. Hurburgh, Alison E. Robertson Sep 2009

Update On Hail Damaged Grain, Charles R. Hurburgh, Alison E. Robertson

Integrated Crop Management News

The situation with the hail damage to crops in north central Iowa is becoming clearer. On Aug. 9, 2009 an intense storm travelled approximately 150 miles from western Sac and Ida counties to eastern Grundy County. The hail swath was about ten miles wide, between Highways I-175 and US-20, with three miles in the middle being almost completely lost. The stones were large, which created major damage to both plants and developing grain. Earlier storms in northeast Iowa also created large losses but the grain itself was less developed.


Degree Days - Watching, Waiting And Staying Warm, Richard O. Pope Sep 2009

Degree Days - Watching, Waiting And Staying Warm, Richard O. Pope

Integrated Crop Management News

A near-perfect week! Sept.13 - 20 provided seasonally normal temperatures, bright sunshine and some light rain at week's end; all of which are favorable to Iowa's maturing crop. As of Sept. 21, the mid-range forecast is calling for night temperatures that should NOT approach killing temperatures. If this bears out, it will mean no early frost in 2009.


Quality Issues Related To Hail Damaged Crops, Charles R. Hurburgh, Alison E. Robertson, Gary P. Munkvold Sep 2009

Quality Issues Related To Hail Damaged Crops, Charles R. Hurburgh, Alison E. Robertson, Gary P. Munkvold

Integrated Crop Management News

The August 23 hailstorm across north central Iowa, and to a lesser extent the earlier northeast Iowa storm, caught crops approaching maturity. The sheer size of the north central event, almost 200 miles long and 10 miles wide, assures that damaged grain will reach the market. Fortunately, weather since the storm has been very favorable for hastening maturity and minimizing mold toxin potential.


Degree Days - Crops In The Cooler Again, Richard O. Pope Aug 2009

Degree Days - Crops In The Cooler Again, Richard O. Pope

Integrated Crop Management News

After three weeks of near-normal temperatures, Iowa weather wrapped up August with a return to colder-than-normal. For the week of Aug. 24 - 31, we gained on average 50 degree days fewer than normal. So where does that put us?


Risk Of Mycotoxins Associated With Hail Damaged Corn, Alison E. Robertson, Gary P. Munkvold Aug 2009

Risk Of Mycotoxins Associated With Hail Damaged Corn, Alison E. Robertson, Gary P. Munkvold

Integrated Crop Management News

Hail storms that occurred recently across the state have caused considerable damage to corn crops that will likely result in reduced yields. Bruises on stalks and ear husks may allow pathogen entrance that could result in stalk and ear rots, and consequently stalk and grain quality issues. In particular, there may be increased risk of mycotoxin contamination on grain.


Degree Days - Cool July With Good Crop Conditions, Richard O. Pope Aug 2009

Degree Days - Cool July With Good Crop Conditions, Richard O. Pope

Integrated Crop Management News

Iowa corn is tasselling and silking this week. We think of the silk date as a marker for the final 60 to 65 days in which the corn reaches physiological maturity. That means we might expect dry down to extend into October across the state. Soybeans are setting pods, and with timely August rainfall, pods should fill nicely. Last week we lost approxiamtely 50 degree days to average across Iowa, making July 2009 as one of the ten coolest in history.


The 2009 Season In Degree Days Through Late August, Richard O. Pope, S. Elwynn Taylor Aug 2009

The 2009 Season In Degree Days Through Late August, Richard O. Pope, S. Elwynn Taylor

Integrated Crop Management News

Degree days are a critical driver of crop development, and 2009 certainly illustrates that point. Wet soils and cool early season temperatures delayed some plantings and also delayed the development of crops that were planted on time. The early vegetative stages were slowed by cooler-than-normal temperatures, then July arrived with a remarkably un-summerlike chill that lasted the whole month.


Degree Days - Entering The Stretch, Aiming For The Finish Line, Richard O. Pope Aug 2009

Degree Days - Entering The Stretch, Aiming For The Finish Line, Richard O. Pope

Integrated Crop Management News

Another week of cool but not too cold weather has positioned the Iowa grain crop well for the final run to harvest. During the week of August 17 we lost a net 50 to 60 degree days to average, but favorable night temperatures allowed for crop condition to improve slightly. The August 24 USDA crop condition report assesses Iowa corn and soybean both at 79 percent good to excellent. Another two or three weeks of good weather and we will begin the final dry-down push to harvest.


Degree Days – Steady As She Goes, Richard O. Pope Aug 2009

Degree Days – Steady As She Goes, Richard O. Pope

Integrated Crop Management News

Another August week down and it was again a favorable week with nearly normal temperatures. What we need most now is to avoid extremes in temperatures throughout the next month, with periodic rainfall. Last week was actually the first in nearly two months that was, albeit slightly, above normal in heat accumulation.


Degree Days - Average Is A Good Thing, Richard O. Pope Aug 2009

Degree Days - Average Is A Good Thing, Richard O. Pope

Integrated Crop Management News

A nearly average week of heat and some rain to boot! August could not have started better for Iowans, except for the band of hail and wind damage along the U.S. 20 / Iowa 175 corridor. For the week, we only lost around 10 to 15 base-50F degree days to average across Iowa. Like they say, just what the doctor ordered (except for the hail!). Statewide, corn development ranges from brown silk (R2) to dough stage (R3), and soybeans are busily filling pods (R4--R5).


Making Fungicide Decisions On Hail Damaged Crops, Daren S. Mueller Aug 2009

Making Fungicide Decisions On Hail Damaged Crops, Daren S. Mueller

Integrated Crop Management News

During the past weekend hail storms once again wreaked havoc on corn and soybean fields across Iowa. Much like hail damage last month and last week, growers have an option to spray fungicides to protect remaining leaf tissue. We wrote an article last month walking through a fungicide decision on hail-damaged crops at that point in the growing season. Much of the information in that article remains relevant.


Degree Days - We Don't Need Stress!, Richard O. Pope Aug 2009

Degree Days - We Don't Need Stress!, Richard O. Pope

Integrated Crop Management News

It is beyond time to get hot summer weather started! Both corn and soybean are (finally) in reproductive stages, and parts of Iowa are over 200 degree days behind normal. But we don't want to make up that deficit with significantly above-normal temperatures, as high August temperatures mean stress that can cut yield potential dramatically. In 1992, we were nearly as far behind as now, and the cool August weather then produced an above-normal yielding crop, however the grain was wet and fall grain handling and dry down were significant issues.


Crops Put In A 4-Day Work Week, Richard O. Pope Jul 2009

Crops Put In A 4-Day Work Week, Richard O. Pope

Integrated Crop Management News

For organisms, heat drives development. If you can regulate your own heat like we humans do every day is a balmy 98.6 or so, so development every day is the same and can be measured by the calendar. But for our field crops and most of the pests they face, development is based on the heat they get from the environment. And, less heat means slower growth. For the week of July 12--19 alone, Iowa normally accumulates 200 base-50 degree days as a statewide average. Last week that accumulation was 133, or about four and a half "normal" days ...


Degree Days - A Bit Wet And A Bit Wild, Richard O. Pope Jul 2009

Degree Days - A Bit Wet And A Bit Wild, Richard O. Pope

Integrated Crop Management News

Iowa weather continued to track cool and wet as degree days fell just a bit further behind long-term averages. With the cooler weather and precipitation since June 1 registering 168 percent of normal, many fields have remained damp.


Should Hail Damaged Crops Be Sprayed With A Fungicide?, Alison E. Robertson, Daren S. Mueller Jul 2009

Should Hail Damaged Crops Be Sprayed With A Fungicide?, Alison E. Robertson, Daren S. Mueller

Integrated Crop Management News

Last week severe storms hit several counties in Iowa with hail ranging from softball to pea size causing significant crop damage. Hail damage to corn may negatively affect yield potential (see Elmore and Abendroth, 2009) but may have little effect on soybean yield potential (see Pedersen, 2008).


Degree Days - Temperature Roller Coaster, Richard O. Pope Jul 2009

Degree Days - Temperature Roller Coaster, Richard O. Pope

Integrated Crop Management News

Iowa crops continue in good condition as we finish one of the coolest July 4 holidays on record. Each of the last three weeks have alternated between above and below normal temperatures. As of July 5, we have accumulated 87 fewer degree days statewide since May 1 compared with the 30-year average. That is roughly equivalent to 3.5 average July 4 days, so we aren't in terrible shape. The cool-warm-cool pattern appears now to continue as the forecast is for above normal temperatures through the middle of July.


Degree Days - Cool Weather Continues, Richard O. Pope Jun 2009

Degree Days - Cool Weather Continues, Richard O. Pope

Integrated Crop Management News

A third straight week of cooler than average weather has slowed crop progress across Iowa. Sporadic rainfall has limited field work, and for many fields weeds are a growing concern (pun intended). There has been slow weed response to herbicides, especially with glyphosate. The answer to this lies in getting some warmer weather to stimulate growth. So patience is a virtue.


Degree Days - Cool Is Cool, Richard O. Pope Jun 2009

Degree Days - Cool Is Cool, Richard O. Pope

Integrated Crop Management News

The month of June opened with a cool week, with about 80 percent of the normal heat accumulated between May 31 and June 7. Although a bit warmer weather would accelerate crop development, Iowa crops are progressing nicely in most areas. Statewide, we have received about 90 percent of the heat for corn and soybean growth as in an average year. We are now 44 base-50 degree days behind average.


Degree Days - Crops In Good Condition Despite Cool Temperatures, Richard O. Pope Jun 2009

Degree Days - Crops In Good Condition Despite Cool Temperatures, Richard O. Pope

Integrated Crop Management News

The 2009 growing season finished off May a bit cool, with degree day accumulations for only one of the nine crop reporting districts, west central, besting its long-term average. May was marginally cooler in the east, although that is not a problem, and crops are off to a great start statewide.


Degree Days - From A Brisk Week To A Balmy One, Richard O. Pope May 2009

Degree Days - From A Brisk Week To A Balmy One, Richard O. Pope

Integrated Crop Management News

Although the week of May 10 was seasonally cold; we made up most of that week's lost heat during the week of May 17. Corn planting is nearing completion across Iowa, and soybean planting is wrapping up in some regions as well. Corn fields should be monitored for black cutworm now, based on pheromone trap capture data.


Degree Days - Brisk, But Basically Ok, Richard O. Pope May 2009

Degree Days - Brisk, But Basically Ok, Richard O. Pope

Integrated Crop Management News

The week of May 10 was seasonally cold; all areas of Iowa fell behind long term average degree-day accumulations. Departures from normal were equivalent to 2.5 days of May growth in northwest Iowa to 3.5 days in southeast Iowa.


Degree Days - Slow But Steady Progress In Planting, Richard O. Pope May 2009

Degree Days - Slow But Steady Progress In Planting, Richard O. Pope

Integrated Crop Management News

Iowa recorded temperatures close to season normals the week of May 4. Seasonal accumulated degree days are hovering near average in all crop reporting districts. Scattered rainfall limited field work in some areas, but statewide another one-fifth of corn acres were planted, raising the planted acreage in Iowa to around 80 percent. Between one-fourth and one-third of the corn can now be rowed. Soybean planting has picked up, and about 20 percent is now planted.


Degree Days - Off On A Muddy Track, Richard O. Pope May 2009

Degree Days - Off On A Muddy Track, Richard O. Pope

Integrated Crop Management News

Today's article is the first weekly post that monitors accumulation of degree days through the 2009 growing season. The map below shows the base 50 degree F days that have accumulated in each of Iowa's nine crop reporting districts, and the departure in accumulations from long-term averages.


A Weather Summary For The 2008 Growing Season, Richard O. Pope Oct 2008

A Weather Summary For The 2008 Growing Season, Richard O. Pope

Integrated Crop Management News

And in a general sense that is a good description, as the Iowa statewide accumulation of crop growth degree days was about 130 behind the 30 year average, and rainfall was more than 7 inches above normal. But when we examine each by crop reporting district through the season, the story gets a bit more complex, depending on where you are looking.


Knee High By When?, Richard O. Pope Jul 2008

Knee High By When?, Richard O. Pope

Integrated Crop Management News

Independence Day has come and gone, and scant acres of corn in most of Iowa have reached that old, outdated saw of knee high by the fourth of July. On my weekend trip to western Iowa, I saw corn ranging from V2 to VT! Admittedly, very little acreage was at either extreme, but it illustrates the continuing range of crop conditions that we will deal with through and after harvest this year.


Degree Days Continue To Lag, Richard O. Pope Jul 2008

Degree Days Continue To Lag, Richard O. Pope

Integrated Crop Management News

Another week of slightly cool days with scattered storms has Iowa farmers facing uneven stands in many fields. Cumulative heat during the week of June 23 lagged behind long term averages by 10 to 25 degree days in Iowa. The cool temperatures and still wet soils provide stresses to struggling crops, and those stresses are showing up in poor growth. As we get more heat the corn and soybean should recover, but this early summer has predisposed the crops to future stresses.


A Cool And Thankfully Dry Week, Richard O. Pope Jun 2008

A Cool And Thankfully Dry Week, Richard O. Pope

Integrated Crop Management News

Some good news this week, with much-needed access to fields gained across Iowa. Also on the positive side, hay harvest progressed rapidly and hay yields were reportedly good. Although the week was a bit cooler than average, the dry weather was a welcome relief.