Friday, October 8, 2010

The 2010 Rice Crop - A Look Back

The 2010 rice crop is near completion with over 90% of the rice harvested. Yields have been less many growers anticipated and in several cases, a failure. While yields for a few growers were actually better than ever, most struggled with yields typically ranging 20-40 bushels/acre less than normal. The number of failures that I have been involved with (less than 120 bushels per acre is really a failure in today’s economic environment) have exceeded what I have experienced in the past 20 years. The USDA has estimated Arkansas yields at 142 bu/acre, which is the lowest statewide yields we have had since 2001.

As you look back and try to prevent these disasters from happening again, here are just a few observations. The heat was certain a factor but, in and of itself, was only partially responsible for lower yields.

Water management proved to be crucial. The heat and drought strained the irrigation abilities of many growers and ultimately caused significant yield losses. Hot spots or areas where water never reached were evident in many fields across the state.

Bacterial panicle blight was widespread and responsible for major losses among certain varieties. This disease was particularly more severe in fields of rice following rice and later planted.

Planting date had a significant effect, as it normally does. However, the date at which yields began to be negatively impacted was much earlier than normal. Because we experienced the heat so early in the growing season that “late planted rice” was most everything planted after April 20.

Low fertility, particularly potassium, was observed in an alarming number of fields. These fields with inadequate fertility often expressed their effects as stem rot, cercospera (narrow brown leaf spot), and to a limited extent bacterial panicle blight.

Excessive rainfall early in the growing season resulted in severe flooding in some areas. Rice was submerged in some areas for an extended period of time and the yields were affected.
Many of these problems will solve themselves if we can avoid record high night-time temperatures and season-long drought. (Much of the state is still in a mild drought). I am certainly ready to put 2010 down as one of the most difficult in the last 25 years and move on to 2011.

PRELIMINARY RICE YIELD TRIALS

Harvest of the 2010 Arkansas Rice Performance Trials has been completed and the yields have been compiled. Preliminary yield results can be downloaded from the Arkansas Variety Testing website (http://www.arkansasvarietytesting.org). I caution that these yields are preliminary and will not be final until complete review. The final report should be completed soon and will be available as a Rice Information Sheet either online at the above web site, at the University of Arkansas Cooperative Extension Service website, or in printed form from you local County Extension Office. The hard copies should be available in January, 2011.

Thursday, September 9, 2010

MY RICE FIELD IS NOT YIELDING WELL, WHAT HAPPENED? (Rick Cartwright and Chuck Wilson)

"The field looked good all year but the rice just isn't there.  What happened?"  After the earliest rice fields were harvested during the first two to three weeks of August, we started hearing this question more and more and recently (last week of August to September 8), more and more fields have been affected.

The following is some of what we have observed in trying to figure out why particular fields are yielding lower than expected.

HEAT – This year has had the highest average temperatures of any summer on record, surpassing 1980. While the day temperatures have been hot, the night temperatures have been the reason for setting a new record. Any year where we have day and night time temperatures as hot as we experienced in June and July, yields and milling quality suffer. The earliest planted rice fields are the least affected and this is true this year and all varieties and hybrids seem susceptible. This does not explain why one field yields well and others around it yield poorly, though. Especially when the fields are planted and managed the same.

WATER MANAGEMENT – When we have day time temperatures of near 100 degrees and night temperatures in the 80’s day after day, and no rain for weeks, establishing and maintaining a flood is extremely difficult. I know guys don't want to hear that they may have water management problems, but... 
It was evident in several fields this year that “hot spots” were developing because the well could not keep up with the demand for water by the rice plant. Also, don’t forget that several fields never saw the first flood until close to midseason. With this heat, we have also observed fields where the flood was simply drained too early and the result was that grain fill was interrupted and yield was off. High spots or later maturing areas of these fields were most affected, as well as the bottom part of panicles on secondary tillers. There also seems to have been some cooling effects observed by well water compared to surface water, which has resulted in higher yields in some cases.

BACTERIAL PANICLE BLIGHT (or panicle blight)- In years where night temperatures are high, like this year, or 1993, 1995, 1998, 2001 etc – we see a lot of problems with this disease. Typically we called this “Bengal” disease because it mostly affected the medium grain variety Bengal over the years. However, it really hot years, the disease developed in long grain fields as well, and heavily damaged Cypress (for example) in 1995 and we have seen it hurt Francis, Cocodrie, Cheniere, Wells and other varieties at times. For whatever reason, it does not appear to affect hybrids and Jupiter (released as partially resistant) does not seem to be susceptible under our conditions.

This year, we have observed bacterial panicle blight in CL 151, CL 111, CL 131, Wells, Francis, Neptune, CL 142AR, CL 261 and Cheniere. Factors associated with the worst fields have been:

rice after rice rotation;
not enough potassium fertilizer;
too much nitrogen fertilizer;
heavy stinkbug pressure;
excessively high seeding rates.

Yield losses up to 50% have been estimated for some fields and this disease appears to be widespread in the state during 2010.



CL 151 field with heavy bacterial panicle blight

Close-up of affected panicles

Close-up of bacterial panicle blight at a more advanced stage on Bengal rice

NARROW BROWN LEAF SPOT AND BROWN SPOT DISEASE – For whatever reason, we are seeing more damage from these two diseases than in previous years, mainly to the panicles and flag leaves in affected fields. Both can cause lesions within the panicle, blanking out spikelets and individual kernels, and on some fields doing heavy damage to the flag leaves. Damage has been observed on several varieties including CL 151, CL 111, CL 131, CL 261, Cheniere (and probably others) as well as the hybrids. Factors associated with fields having the most disease include not enough potassium fertilizer; rice after rice rotation; and later planting dates.

Close-up of narrow brown leaf spot infecting panicle of rice
(resembles blast sometimes and brown spot can cause this also)


STRAIGHTHEAD – We have observed and had more reports of true straighthead than normal. This is an old disease of rice in the state, associated with certain fields. Dark green, normal sized leaves and stems, with blanked and distorted kernels only in the flooded paddies (not on levees) would be typical symptoms. However, some long grain rice varieties including Cocodrie, do not display a lot of parrot-beaking in the kernels but usually you can find some if you look hard enough. Medium grain varieties are more likely to show a lot of parrot-beaking, in our experience. Straighthead occurs each year in susceptible fields when rice is planted and the flood is not drained at the proper time to prevent the disease. Some fields this year that have reported straighthead symptoms have no history of the disease, so in these cases, we would be suspicious that you may be dealing with something else. We have had a lot of calls on Cheniere this year, and have observed some fields with symptoms, and we are not sure what is going on because in the past Cheniere has been pretty resistant to true straighthead in Arkansas. In the fields where we have seen what appears to be true straighthead on Cheniere, the variety does not look exactly like the Cheniere we have evaluated in the past. And these fields have had neck blast scattered across the same fields, another disease that Cheniere has not had a problem with in the past under our conditions.

Straighthead on Cocodrie, note little parrot-beaking

Severe parrot-beaking on a different rice variety, note full size leaf

STINKBUGS – It seems to have been a record stinkbug year, and many fields we have been in have the “odor” of heavy stinkbug pressure. In many cases, 2 or 3 applications of insecticides were made to try to control this insect. However, in some fields, there was still damage including blanking and pecky rice. We suspect an association with this insect, and possibly other arthropods on rice, and bacterial panicle blight but have no conclusive proof of this. It just seems the disease is worse in fields with high populations of stinkbugs. Regardless, we should not underestimate the direct and indirect effect of this insect on yield and quality in rice this year.

GLYPHOSATE DAMAGE – We planted most of our rice early this year, but planted most glyphosate resistant soybeans later than normal. This lined up drift problems to rice in certain areas of the state again, and we have walked a number of fields thought to have straighthead that actually were damaged by late glyphosate drift when the rice was at a sensitive stage. Glyphosate causes parrot-beaking and other distortions and blanking of the kernels, and depending on the growth stage when drift occurred may cause shortening and distortion of the flag leaf, or at least distortion and a leathery feel to the base of the upper leaves. Yield loss can be heavy and affected plants can be found in flooded paddies or on levees, unlike straighthead, and usually there is an association with the source of the drift – a nearby glyphosate resistant soybean or cotton field, etc.

Severe glyphosate injury to rice
(symptom severity varies a lot in affected fields)

STEM AND SHEATH DISEASES – We have been in a number of fields damaged by stem rot this year, a disease that seems to like hot summers. It also likes low potassium and rice after rice, so fields that have not been fertilized or rotated properly have the most damage. Symptoms include lodging and stem lesions, as well as blanking of the base of panicles on affected tillers. Other stem diseases can cause some of this as well, and we have observed several fields of hybrid rice where black sheath rot (crown sheath rot) and possibly other sheath diseases have weakened the lower stems – causing lodging - and blanked out some kernels.

Lower potassium field with lodging caused by stem and sheath diseases

IN MANY PROBLEM FIELDS WHERE YIELDS ARE LOW THIS YEAR, WE HAVE OBSERVED TWO MANAGEMENT ISSUES CONSISTENTLY – NOT ENOUGH POTASSIUM FERTILIZER AND RICE PLANTED AFTER RICE. BOTH ARE DECISIONS THAT RESULT IN LOWER YIELDS AND MORE DISEASE PROBLEMS.

Wednesday, August 11, 2010

Rice Stink Bug Alert!

(Dr. Gus Lorenz)
We are observing large numbers of stink bugs moving into rice fields that are in the 3rd and 4th week of heading. We are observing numbers as high as 4x threshold. This is occurring in all rice growing regions

of the state. These are fields where the rice panicles/ seed are in the milk or soft dough stage. Stink bug feeding at this time can cause "pecky rice", which can result in significant discounts on the price received when the rice is sold.

Rice is not safe from damage until it reaches the hard dough stage. If the rice grain is still soft and pliable or can be squeezed between your fingers, it is still susceptible to damage. In many cases the oldest part of the panicle is hard dough but the base of the panicle is still soft dough. This is a field-by-field call. Just remember the discount for peck can be severe and best avoided.

The threshold for rice stink bugs is one per sweep. Take 10 sweeps in several locations in the field if you are averaging 10 stink bugs per 10 sweeps you need to make an insecticide application. Recommended products are pyrethroids such as Karate or Mustang Max or methyl parathion. Do not release the flood water within 7 days of application. Also be advised that when sampling during the hot part if the day, stink bugs move down in the plant and sampling at this time may not reflect the true number of stink bugs. Sampling is most effective early in the morning and late in the evening when the bugs are out on the panicles. Sweepnets are much more effective than "visual observations".

Thursday, August 5, 2010

RICE FIELD DAY NEXT WEEK!

The University of Arkansas Rice Research and Extension Center will host its annual Rice Field Day on Wednesday, August 11, 2010 beginning at 7:30 am. There will be one field tour with departure times of 7:30, 8:00, 8:30, and 9:00 am. Topics on the tour include hybrid rice breeding, nitrogen soil test for rice, soybean production, rice weed management, rice disease management, and new rice varieties. Come and see our new laboratory and office facility and check out new technology in rice.

Is it time to drain my rice yet?

I realize that several farmers have already started draining, and even harvesting in some cases. However, I thought this might be helpful in light of the heat and drought conditions we are currently experiencing. Farmers are always interested in when I can quite spending money on irrigation and begin to prepare for harvest. This has been especially true this year in light of the high input costs already paid out for this crop. For the majority of the rice acreage, we recommend draining 25-28 days after 50% heading. This generally corresponds to the time when the heads have all turned down and most of the panicles have changed color at least half way down the panicle. The photos below illustrate what rice typically looks like 25 days after 50% heading. The three panicles in the second photograph were taken from the plot in the first photograph.


Research varies on the effects of earlier draining but some studies have reported yield losses as much as 10% when drained too early. Remember in this heat, soils dry quickly. Don’t over estimate the amount of time is will take for the soils to dry. One option to help reduce pumping costs is to establish a good flood 14 days after 50% heading and then let the field dry down. This works for some growers but others have indicated that removing levee gates is too difficult if the fields dry out before drain time. In hot, dry years like this year, you still may need to flush through the fields if you don’t get any rainfall to help the crop to mature. If you routinely must rut the field in order to get the rice harvested on time because the fields do not dry enough, earlier draining is a feasible option. This is usually the case on most heavy clay fields.

WHAT ABOUT "SALTING" MY RICE?

Sodium chlorate is commonly used to desiccate green foliage and weeds present in rice fields to increase harvest efficiency. The general guidelines are to apply sodium chlorate at 3 to 6 pounds a.i. per acre when rice grain is near 25 percent moisture and harvest within 3 to 7 days after application. Although sodium chlorate is typically used to dessicate the vegetation, grain moisture is also reduced. Research suggests that when used properly sodium chlorate does not reduce head rice yield. However, application of sodium chlorate at 6 pounds a.i. per acre significantly reduced grain moisture by 2 to 5 percent within four days after application. Head rice yields may decline if grain moisture drops below 15 percent before the grain is harvested. Thus, sodium chlorate should be applied to rice that is between 18 and 25 percent moisture with timely harvest following application. Use of sodium chlorate on seed production fields is sometimes needed. Research has shown that sodium chlorate does not influence germination of the resulting seed.

Desiccation of rice foliage is noticeable within 36 hours after application, especially when temperatures are high. The photo above was taken less than 48 hours after application.  The treated plots are very apparent and dessication was very effective. Sodium chlorate may reduce head rice and grain yield if applied too early, before grain fill is complete. Do not apply to rice when the moisture is above 25%. Growers should exercise caution when considering sodium chlorate application to fields with uneven maturity to avoid yield and quality losses.

August 5 Rice Crop Condition and Progress

As of August 2, the USDA reports that 74% of the crop is heading and a couple of fields have been harvested. This compares to 57% heading last week, 28% this time last year, and a 5-year average of 39% for this week. Arkansas rice does not normally begin heading in June nor is it normally harvested in July. The first rice harvested in Arkansas that I am aware of was on July 30. Harvest has begun in some areas this week and will get going strong in about 2 weeks. As of August 2, 18% of the crop is reported to be in excellent condition, 44% good, 31% fair, 6% poor, and 1% very poor.


Average temperatures for the week ending August 2 ranged from 0 to 5 degrees above normal. The temperatures ranged from a low of 68 degrees at Gilbert and Calico Rock to a high of 104 degrees in Camden, with several locations exceeding 100 degrees. Rainfall for the week ending August 2 ranged from none at several locations to a high of 3.2 inches at Hot Springs. Overall, soil moisture supplies were 13% very short, 56% short, 29% adequate, and 2% surplus. The extended heat and dry weather have caused a significant strain on the irrigation capacity across the Delta. Rice fields have spots (some large, some small) that are burning because the well is unable to keep up with the dry weather. Officially, most of Eastern and Southern Arkansas is “moderate drought”, parts of Southeast Arkansas is in “Severe drought”.

Monday, July 26, 2010

IDENTIFYING BACTERIAL PANICLE BLIGHT AND NECK BLAST OF RICE

(by Whitney Ginn and Rick Cartwright)
We are currently observing widespread neck blast of rice in Arkansas for the third year in a row, largely on the rice varieties CL 151, CL 261, Francis, Jupiter and at lower levels on Wells and CL 142. The blast problem was likely increased by frequent May rains that resulted in a lot of leaf blast in the state, followed by erratic drought patterns that made keeping a deep, consistent flood on rice fields difficult.

Recently, we also began noticing symptoms of bacterial panicle blight developing in fields of CL 261 and CL 181, and at low levels in CL 151, CL 142, CL 111 and Francis. Weather patterns in recent weeks have included very warm nights with high humidity, conditions that favor this disease. We are hopeful that bacterial panicle blight will stay at low levels, but early observations concern us that this may be a panicle blight year like we saw in 1995, 1998, and 2001 on Bengal and a few other varieties.

Distinguishing between bacterial panicle blight and early neck blast symptoms is not difficult, with some practice. The following photos illustrate the diagnostic differences.

Bacterial Panicle Blight: Note the cluster pattern of early infected heads (A), with a mixture of tan, green, brownish or gray kernels – but a green rachis (panicle branches)(B). At least some kernels will have a distinctly brown base (C) and inside the small kernel will be aborted and rotted at the base.

Neck blast of rice: Note the “white heads” in affected field (D) and the dark lesion on the node below the infected panicle (E); dark lesions may also appear in the rachis, resulting in blighted spikelets or kernels; earlier lesions of blast can be found on leaves, collars and lower stem nodes (G); spores can be easily observed at 100X if a microscope is available (F).

Tuesday, July 20, 2010

July 20 Rice Crop Condition and Progress

As of July 19, the USDA reports that 37% of the crop is heading. This compares to 16% last week, 9% this time last year, and a 5-year average of 9% for this week. Arkansas rice does not normally begin heading in June but we saw that happen in 2010. The crop was seeded earlier and we had 8 straight weeks with temperatures above normal. Thus, the crop has developed much sooner than normal. As of July 19, 21% of the crop is reported to be in excellent condition, 44% good, 30% fair, and 5% poor.

Average temperatures for the week ending July 19 were near to slightly above normal. The temperatures ranged from 1 degrees below normal at Newport to 4 degrees above normal at several locations. The temperatures ranged from a low of 68 degrees at several locations to a high of 100 degrees in Little Rock and El Dorado. Rainfall for the week ending July 12 ranged from none at Hope and El Dorado to a high of 7.0 inches at Fayetteville. Overall, soil moisture supplies were 5% very short, 29% short, 59% adequate, and 7% surplus. The extended heat and dry weather have caused a significant strain on the irrigation capacity across the Delta. Rice fields have spots (some large, some small) that are burning because the well is unable to keep up with the dry weather. Officially, most of Eastern and Southern Arkansas is “abnormally dry”, which is effectively a mild drought. These data are collected as of Friday and do not reflect the rainfall that has occurred in much of Eastern Arkansas.

Tuesday, July 13, 2010

TIMING FOR BLAST FUNGICIDES

To minimize neck blast with current fungicides, the products MUST be applied preventatively – before the panicles have emerged fully from the boot. The photos below illustrate growth stages for application of the fungicides registered for neck blast prevention, based on the most severe disease pressure situation =[ highly susceptible variety (example = CL 151, Francis, CL 261) + erratic flood depth or shallow flood depth + field with a history of blast disease, etc.].

The photo first photo below is equivalent to late (fully swollen) boot to boot split (5% heading) and is appropriate for the first application. The second photo is equivalent to 50-90% heading and is appropriate for the secondapplication. Note that the bases of all panicles are still in the boot. We believe that when the base comes out, the neck of the panicle often gets infected at that point, and once the fungus is inside, fungicides cannot do much to prevent subsequent damage.


For one-shot applications to a field, the best timing is between these two growth stages, when about 1/3 of the panicle is emerging from the boot (30-50% heading), as seen in the first photo, far right tiller. It is always better to err on the early side of these stages, than later. In most cases, a late boot to boot split application can be followed by the second application in 5 days and things should work out.

While 19 oz of Stratego at full boot to boot split, followed by 12 oz of Quadris at the second timing is a good program to minimize neck blast in fields with severe disease pressure in Arkansas, 12 oz of Quadris followed by 12 oz Quadris and 21 oz Quilt Xcel followed by 12 oz Quadris are also effective choices. Please keep in mind that Stratego and Quilt Xcel have 35 day PHI restrictions while Quadris has a 28 day PHI, and fully read these labels for other guidelines and restrictions.

July 12 Rice Crop Condition and Progress

As of July 12, the USDA reports that 16% of the crop is heading. This compares to 8% last week, 5% this time last year, and a 5-year average of 3% for this week. Arkansas rice does not normally begin heading in June but we saw that happen in 2010. The crop was seeded earlier and we had 8 straight weeks with temperatures above normal. Thus, the crop has developed much sooner than normal. As of July 12, 21% of the crop is reported to be in excellent condition, 43% good, 30% fair, and 5% poor and 1% very poor.


Average temperatures for the week ending July 12 were near normal for the first time in several weeks. The temperatures ranged from 2 degrees below normal at Hot Springs to 3 degrees above normal at Keiser. The temperatures ranged from a low of 58 degrees at Batesville to a high of 97 degrees at Camden. Rainfall for the week ending July 12 ranged from a trace at Stuttgart and DeQueen to a high of 6.1 inches at Mountain Home. Overall, soil moisture supplies were 14% very short, 36% short, 50% adequate, and 2% surplus. These data are collected as of Friday and do not reflect the rainfall that has occurred in much of Eastern Arkansas. The extended heat and dry weather have caused a significant strain on the irrigation capacity across the Delta. Rice fields have spots (some large, some small) that are burning because the well is unable to keep up with the dry weather. Officially, most of Eastern and Southern Arkansas is “abnormally dry”, which is effectively a mild drought. These data are collected as of Friday and do not reflect the rainfall that has occurred in much of Eastern Arkansas.

The USDA acreage report indicates that we have planted record rice acreage in Arkansas in 2010. The planted acreage is estimated at 1.681 million acres, up 13% from last year’s planted acreage of 1.486 million. The 1.681 million acres is also 38,000 over the previous record acres of 1.643 million planted in 2005. If the forecasts for good yields are realized, record production is likely. However, the heat and drought coupled with the amount of rice planted on marginal soils are not likely to allow us to harvest a record yield. Very early estimates suggest that CL 151 is the most widely planted variety so far (about 23% of the acreage). The next most widely planted varieties are Rice Tec CL XL 745 (18%), Wells (17%), and Jupiter (12%). These numbers are preliminary and may change as we get more information available.

Thursday, June 24, 2010

Sulfur and Potassium Deficiency in Rice

During the past few days, we have received a few calls about suspected sulfur and potassium deficiency in rice. The deficiency symptoms can be confusing and hopefully we can provide some assistance in distinguishing these problems from other stem and leaf diseases.


Sulfur deficiency of rice: The following images show leaf symptoms of sulfur deficiency. We rarely see this in Arkansas and it is usually in patches or areas of fields, often associated with sandy regions but may be reported on “cut” spots as well. In the latter, it may be associated with other deficiencies from what we have observed.

Sulfur deficiency shows up in the upper leaves, from a distance appearing dull or bright yellow, at least at first.

Closer examination may show shortened leaves with tip discoloration (yellowing) following by the formation of rows of brown spots between the veins proceeding from the tips downward.

Another view of the tip discoloration and the spotting between veins.

Potassium Deficiency: Many silt loam rice soils in Arkansas are low in available potassium. Rice grown on these soils is subject to potassium deficiency, which often gets noticed during the early to mid booting stages, and to more severe stem rot and brown spot.



As shown above, potassium deficiency may show up as a later season tip discoloration. From a distance, patches in the field may turn reddish or brown and seem to spread across the field over time as the plants become deficient over larger areas. Wells rice shows this symptom as reddish tip discoloration, and the affected length of leaves may be several inches from tip downwards.

If you examine rice plants in suspected potassium deficiency areas, you may find increased disease symptoms of stem rot as above, in severe cases killing the stems resulting in partially blanked discolored panicles.

You may also notice severe brown spot as above. This often occurs on deficient Bengal and other rice varieties.

Sometimes, rice developing deficiency earlier in the season will be stunted, with more yellowing of the tips of the lower leaves and tip discoloration.

An unexplained tip discoloration symptom that shows up during booting is the so-called “high yield disease”. Sometimes lush, rapidly growing rice fields will exhibit widespread tip discoloration of the field usually on the 3rd leaf down. This is the leaf that is sticking up the tallest for a while at early boot, until the flag and flag minus one leaves are fully developed. The discoloration is usually yellowish to a light brown and the leaf tips may have some spots, etc on them, however tip discoloration is very mild and remains so compared to true deficiencies which continue to move down the leaf tips pretty quickly. The above phenomenon has been associated with lush, high yield potential fields in the past, thus the nickname.

If caught in time, nutrient deficiencies may be stopped by the application of “rescue” fertilizer applications but these attempts are too late to prevent yield losses. They may stop progression of the symptoms or help slow diseases a bit. Greater success for salvaging these situations is achieved with early detection.

One of the biggest challenges with potassium deficiency is what is known as “hidden hunger”. This occurs when the plants are slightly deficient in potassium but no visable deficiency symptoms are displayed by the plant. Because of this situation, we strongly recommend adequate soil sampling and application of preplant potassium as recommended. We have observed significant yield increases from potassium from plots exhibiting only mild or no deficiency symptoms until it is too late.

Wednesday, June 23, 2010

June 23 Rice Crop Condition and Progress

As of June 20, all of the rice in Arkansas has emerged. Early rice should be heading within the next 2 weeks. This means that the optimum timing for sheath blight and kernel smut fungicides is approaching. As of June 20, 20% of the crop is reported to be in excellent condition, 50% good, 26% fair, and 4% poor.

Average temperatures were above normal ranging from 4 degrees above normal at Texarkana to 8 degrees above normal at several locations for the week ending June 20. The temperatures ranged from a low of 64 degrees at Calico Rock to a high of 101 degrees at El Dorado and Eudora. This completes 4 straight weeks and 5 of the last 6 weeks with temperatures significantly above normal. Rainfall for the week ending June 20 ranged from none at several locations to a high of 1.53 inches at Harrison. Overall, soil moisture supplies were 13% very short, 47% short, 38% adequate, and 2% surplus. The extended heat and dry weather have caused a significant strain on the irrigation capacity across the Delta. Rice fields have spots (some large, some small) that are burning because the well is unable to keep up with the dry weather. The impact of this heat will be significant if the weather pattern continues after the rice begins heading.

The National Weather Service publishes a national drought monitor weekly on the web. To view this site, go to: http://drought.unl.edu/dm/monitor.html.  This site provides a map that illustrates the level of drought in the various regions of the US.

Very early estimates suggest that CL 151 is the most widely planted variety so far (about 23% of the acreage). The next most widely planted varieties are Rice Tec CL XL 745 (18%), Wells (16%), and Jupiter (12%). These numbers are preliminary and may change as we get more information available.

Tuesday, June 15, 2010

June 15 Rice Crop Condition and Progress

The weather this spring has allowed rice to be planted across most of the state at record pace. As of June 13, all of the rice has emerged. This compares to 99% last week and 95% this time last year. Our planting progress has proceeded about 2-3 weeks ahead of the 5-year average and a month ahead of last year. As of June 13, 19% of the crop is reported to be in excellent condition, 51% good, 26% fair, and 4% poor.

Average temperatures were above normal ranging from 3 degrees above normal at Conway and Hot Springs to 7 degrees above normal at several locations for the week ending June 13. The temperatures ranged from a low of 56 degrees at Calico Rock to a high of 99 degrees at Stuttgart and Keiser. This completes three straight weeks and 4 of the last five weeks with temperatures significantly above normal. In addition to early planting, the warm temperatures have allowed the crop to progress much quicker. Rainfall for the week ending June 13 ranged from none at several locations to a high of 3.23 inches at Dardanelle. Overall, soil moisture supplies were 2% very short, 28% short, 60% adequate, and 10% surplus.

While some rice is just emerging, the early rice is at early boot stage. Keep a close watch for rice blast and do the best you can to keep susceptible varieties flooded. Leaf blast has been reported in rice counties from North to South.

Very early estimates suggest that CL 151 is the most widely planted variety so far (about 23% of the acreage). The next most widely planted varieties are Rice Tec CL XL 745 (18%), Wells (16%), and Jupiter (12%). These numbers are preliminary and may change as we get more information available.

Don't Forget to Enroll Late Fields in DD50 Program

Early fields should be scouted carefully as midseason approaches. The warmer temperatures have caused the crop to progress quicker than predicted by the Rice DD50 Program in some cases. As the later rice emerges, be sure to enroll those fields in the Arkansas Rice DD50 Program. Five new varieties have been added to the program for 2010. The program can be accessed through the county Extension office or online at: http://dd50.uaex.edu/dd50Logon.asp. In order to enroll, you need the variety name, the emergence date, and the number of acres. The program will predict the timing of approximately 27 different production practices. This allows growers and consultants to be more efficient in scouting the crop and more timely with treatments. On-time decisions can often be the difference between success and failure. It is also important to the industry to enroll these fields. The data helps the mills prepare for harvest while it also serves to estimate the important varieties across the state.

Herbicide Injury Appears Again

I have looked at a couple of fields that have experienced Permit injury similar to what we have seen in the past.  The common symptoms include bright, distinctive yellowing about 7 days after flooding similar to what would be expected with sulfur deficiency, some stunted growth but not always severe, typically occurs on silt loam soils with high soil pH, and normally recovers within about 2 weeks. The yellowing is similar to what is observed with clorimuron (Classic, Canopy XL) carry-over into rice. The yellow color also resembles Newpath injury. All of the compounds are similar and have similar modes of action. Plant tissue analysis normally suggests that the plant nutrient status is normal (i.e. nothing is deficient). A few years ago, we were able to observe the injury in sprayed and unsprayed areas of a field. This allowed us to verify our suspicions.

The green rice in the above photo is an area that was not sprayed and obviously resulted in no rice injury but also no nutsedge control. While the rice seems to be severely affected, little or no yield loss has been observed in the fields where this has occurred.


While this may explain the yellowing in some fields, there are other problems that may be occurring. I am aware of a couple of fields in the past that have similar symptoms and Permit was not applied to the fields.

Draining the fields has been a common practice to get the field to recover. Various fertilizers have also been used with ammonium sulfate being most common. While the fertilizer is only going to correct nutrient deficiencies that may result from the rice being stressed, the nitrogen may help encourage the crop to recover more quickly.

Wednesday, June 9, 2010

Managing Rice Blast and Straighthead

The following questions have arisen repeatedly the last few days:


Question:

We have found blast lesions on CL 151 and CL 142 recently. How concerned should we be about each one and how should we manage to minimize neck blast later on each?

Answer:

You should be more concerned about CL 151 than CL 142. CL 151 is very susceptible to neck blast and under favorable conditions, can be difficult to manage with respect to this disease. If leaf blast is found, or the field has a history of blast or has blast potential (erratic flood history, tree lines, river bottoms, sandy or other water percolating soil type) then you should pump up the field to a minimum 4 inch flood depth in the shallowest part of the field and try to maintain the rest of the season. If you find areas that are burning down from leaf blast, you should consider treating these regions (usually along edges or tree lines) with an application of Quadris, Quilt Xcel, Quilt, Gem or Stratego to minimize blast spore production for the field. If you are spraying the field for sheath blight anyway, the sheath blight application should suffice, depending on timing. If the field does not have hotspots, but only scattered leaf blast, this is not a step I would consider. CL 151 fields with any evidence of leaf blast should be sprayed twice to minimize neck blast, once at boot split and the second about a week later when the earliest heads are about 3/4 out of the boot. You should not cut rates either on this variety. Fields should be scouted extensively in June to mid July to determine leaf blast as lesions tend to disappear during boot to early heading for most observers.

CL 142 is less susceptible to blast in our limited experience than CL 151. It reacts more like Wells, so far. Again, pump up the field if leaf blast is found or in fields with a strong history or potential for blast. Fields like this should probably be sprayed at boot split for blast. Since this variety seems to behave like Wells, the second application and rates are subject to field judgment. If conditions are hot and dry, you can probably get by with less fungicide and perhaps one application. If this is the decision, make sure the fungicide application made is the boot split one, as it is more important. For both CL 151 and CL 142, this application is also appropriate for sheath blight control, if this disease has not been that aggressive earlier.

Question:
Is Taggart resistant to straighthead and how should it be treated to prevent this disease?

Answer:

Based on two straighthead nurseries observed in 2009, we rated Taggart as resistant when compared to susceptible checks like Cocodrie and CL 131 (very susceptible). On typical fields, Taggart will likely not need to be drained or drained "dry to cracking", based on this experience. On fields with a very strong history of straighthead, it may be beneficial to drain most varieties, but resistant ones will not require as much drying as susceptible varieties, and the benefit will not be as great, obviously. On these fields, if it is raining to the degree that draining cannot be done, a variety like Taggart will still perform, whereas Cocodrie and the like will be devastated.

Tuesday, June 8, 2010

LATE PLANTED RICE VARIETIES

There are still a few folks trying to plant some rice. The most common question is what variety is the best to plant in June. In general, the best varieties are the best varieties planted late. Later maturing varieties do better than earlier maturing varieties. The hybrids are good selections because of the yield potential and disease resistance. My experience with the Clearfield varieties is that tend to lose more yield potential when planted in June that many of the conventional varieties. Be cautious about the increased risk for rice blast. Francis does well planted late, as long as you can manage the flood effectively to control rice blast.

Ultimately, all varieties are going to yield less than they would have if they had been planted in April. Decisions should be made with the assumption that my yield is going to be no more than about 120 bushels/acre. I know that higher yields can be obtained with June planted rice. It is better, however, to expect less than what you get than to get less than enough to make ends meet.

RICE DISEASE UPDATE

It seems the worst disease affect rice of late is self-inflicted. Newpath drift has been widespread. When the wind gets high, the farmers start getting nervous about getting their fields sprayed, we don’t always use good judgment. I know that the longer we wait, the bigger the grass gets. But if we can’t keep it in the field, the big grass is going to seem like a rather small problem. The general misconception is that Newpath does not drift. However, we have tracked cases for more than a mile. The earliest fields are reaching midseason and the impact of Newpath drift onto conventional rice is now even greater. Significant yield losses will be observed if the drift occurs after the rice reaches midseason. We need to be especially cautious around conventional rice.

In regard to true disease problems, rice blast month (June) has officially started with the first reports of leaf blast. Leaf blast has been found on fields of CL 151 and CL 142 in central Arkansas and in southeast Arkansas. Finding leaf blast in June is normal and it allows you to prepare for managing the disease early. A deep flood is the most effective control measure to prevent or reduced neck blast or panicle blast later in the season. Fields should be flooded as deep as possible (4-6 inches on the shallow side) until maturity. Scouting now is critical to be able to manage for the disease later.

WHAT ABOUT FOLIAR FERTILIZERS FOR RICE?

It seems the salesmen are active convincing growers to invest in foliar fertilizers for rice. They seem like a good deal, but are they? It greens the crop so it must be “doing some good”, right? Well, maybe for some micronutrients, but probably not for most nutrients.

For rice, zinc is the only fertilizer that the University of Arkansas recommends a foliar application. Even then, applying liquid zinc is not the preferred method. I have received questions about applications of boron, managanese, and other micronutrients to rice. We have no data to support these recommendations. Even in fields where soybeans do respond to boron, application of boron to rice has not been beneficial.


The major nutrients, such as nitrogen, potassium, phosphorus, and sulfur are needed by the plant in large quantities. The amounts taken up by the plant range from as little as 25 lbs/acre for sulfur to as much as 200 lbs/acre for nitrogen. Liquid fertilizer (almost all kinds) typically weighs about 10 lbs for each gallon. The amount of nitrogen in the fertilizer is about 3.2 lbs for each gallon (32%). To get 100 lbs of nitrogen, you need to apply over 30 gallons per acre. A pound is a pound is a pound. Regardless of the form, if the plant requires 90 lbs of potassium, the plant requires 90 lbs regardless of whether it is applied as a granule or in a liquid. When adequate amounts of liquid fertilizer are applied to rice, foliar burn is often a problem. Because of these problems, granular fertilizer is for the major nutrients are much more effective.

The only micronutrient that is recommended by foliar application for rice is zinc. The preferred method of applying zinc is to apply zinc sulfate (36% zinc) prior to planting. Zinc seed treatments are effective if the soil test levels are only moderately low. However, if the rice has emerged, foliar application of zinc is effective when applied prior to flooding. At least 1 lb/acre of zinc should be applied when using liquid zinc products. For most products, this will require a minimum application rate of 1 gallon of liquid zinc per acre. This is true for any product that is 10% zinc or less. While some products have been marketed at 1 quart or 1 pint per acre rates, these rates are not sufficient to prevent zinc deficiency on soils with low soil test zinc levels.

JUNE 8 RICE CROP CONDITION AND PROGRESS

The weather this spring has allowed rice to be planted across most of the state at record pace. As of June 6, rice planting is finally complete. This compares to 99% last week and 97% this time last year. Rice planting is typically complete during the second week of June, although a few acres may actually still be planted later. The USDA estimates that 99% of the rice acreage has emerged. This compares to 89% last year at this time and 96% for the 5-year average. Our planting progress has proceeded about 2-3 weeks ahead of the 5-year average and a month ahead of last year. As of June 6, 18% of the crop is reported to be in excellent condition, 53% good, 25% fair, and 4% poor.

Average temperatures were above normal ranging from 4 degrees above normal at several locations to 8 degrees above normal at Keiser and Brinkley for the week ending June 6. The temperatures ranged from a low of 61 degrees at several locations to a high of 98 degrees at El Dorado. Rainfall for the week ending May 30 ranged from none at several locations to a high of 1.9 inches at Mena. Overall, soil moisture supplies were 2% very short, 29% short, 64% adequate, and 5% surplus.

Much of the rice is reaching the stage for flood establishment and several thousand acres have already been flooded. Remember to wait until the soil dries to apply preflood nitrogen fertilizer and then apply a shallow flood as quickly as possible. Some rice has reached midseason. Remember that a there is a window for applying midseason N between green ring and ½” internode elongation.

Very early estimates suggest that CL 151 is the most widely planted variety so far (about 23% of the acreage). The next most widely planted varieties are Wells (16%), Rice Tec CL XL 745 (16%) and Jupiter (12%). These numbers are preliminary and may change as we get more information available.

Tuesday, May 25, 2010

May 25 CROP CONDITION AND STATUS

The weather this spring has allowed rice to be planted across most of the state at record pace. As of May 23, farmers had planted an estimated 98% of the rice acreage. This compares to 97% last week and only 79% this time last year. It is also ahead of the 5-year average of 92% for this week. The USDA estimates that 95% of the rice acreage has emerged. This compares to 65% last year at this time and 81% for the 5-year average. Our planting progress is 2-3 weeks ahead of the 5-year average and a month ahead of last year. As of May 23, 16% of the crop is reported to be in excellent condition, 52% good, 27% fair, and 5% poor.


Average temperatures were near normal ranging from 1 degrees below normal at Conway to 3 degrees above normal at Monticello and Little Rock for the week ending May 23. Low temperatures ranged from 48 degrees at Calico Rock to a high of 94 degrees at Brinkley and Little Rock. Rainfall for the week ending May 23 ranged from a low of a trace at West Memphis to a high of 3.4 inches at Morrilton. Overall, soil moisture supplies were 6% short, 67% adequate, and 27% surplus.

Much of the rice is reaching the stage for flood establishment and several thousand acres have already been flooded. Remember to wait until the soil dries to apply preflood nitrogen fertilizer and then apply a shallow flood as quickly as possible.

PREFLOOD UREA CRITICAL TO HIGH YIELDS

Most growers know the importance of nitrogen fertilizer on their rice crop. However, it is important to remember that the preflood nitrogen sets the yield potential for the crop. Midseason nitrogen may help the crop when the nitrogen has “run out”. However, midseason nitrogen usually cannot make up for mis-managed preflood nitrogen. Because of this, it is always a good idea to refresh our memory of how management decisions can impact the rice crop’s ability to get the most of the fertilizer.

Urea needs to be applied to dry soil to prevent loss. Even when it seems that it is not possible to get the soils dry, patience is king. The loss from fields where urea has been applied to early tillering rice in muddy or flooded soils can approach 50-60%. Even with Agrotain, the loss on muddy soil can approach 25%. Application of Agrotain-treated urea to dry soil results in less than less than 5-10% loss. Since less nitrogen is lost, rice uptake is more efficient.

Agrotain is worth the investment for most producers. If you can flood in 2 days or less, you probably don’t need Agrotain. Otherwise, Agrotain is recommended. There are other products being promoted as “Agrotain alternatives”, “generic Agrotain”, or “Agrotain replacements”. We have tested N-Zone, X-tend, Nutrisphrere, and Upgrade and found that Agrotain is the only product that reduces ammonia volatilization losses.

How dry is dry? That is often the question when I recommend that urea should be applied to dry soils. In general terms, if the soil is wet enough to leave tracks when you walk, it is too wet to apply fertilizer. Also remember to think about your levee ditches. If you have several levees and can’t afford to lose that rice, the levee ditches need to be dry also.

Monday, May 24, 2010

PREFLOOD CONTROL OF LARGE BARNYARDGRASS

Many calls are coming in right now on preflood grass control. This is a time when many turn to RiceStar HT to take out larger grass or grass that is resistant to propanil, Facet or both. The federal label for RiceStar HT goes up to 17 oz/A, however, in Arkansas we have a State 24C label for rates as high as 24 oz per acre. When do you need the higher rate? Pretty simple, the larger the grass the higher the rate. On small grass, 2-3 lf, 17-18 oz of RiceStar will do the trick. As barnyardgrass and other grass gets bigger, I up the rate. At 2-3 tiller grass I pull the trigger on the 24 oz rate. I may also suggest some Facet to help out.

What about Clincher. I think that Clincher can perform about as good as RiceStar HT on most grass weeds if they are small. I like Clincher early in the season tank-mixed with a residual product on 1-3 lf grass. I like the higher rates of RiceStar HT on larger grass preflood, especially if conditions get dryer. Once we get to post-flood, I think Clincher has performed a little better than RiceStar HT. One exception to this is fall Panicum, I usually recommend 15 oz/A of Clincher, regardless of timing.

If it is a true pre-flood timing, that is your going to flood now, I say apply the RiceStar HT and flood. However, often we may be another week to 10 days from flood. If this is case, add a residual grass material to extend the weed control until you get a flood on. Command (8oz), Prowl H2O (2 pints), or Facet (0.33 to 0.5 lb/A) will usually do the trick.

On Clearfield rice preflood applications, it often takes a leap of faith to apply Newpath and flood. Often there is grass present that is sick, but not dead. Also, for whatever reason, the grass may not be sick at all. If it is below the 3 leaf stage Newpath should do the trick. If it has reached the 4 leaf to 1 tiller stage I add Facet or RiceStar HT to help clean it up. Usually barnyardgrass that is sick will not survive a second shot of Newpath and the flood. Newpath is weak postemergence on sprangletop and fall panicum. I have not seen an advantage from increasing the Newpath rate from 4 to 6 oz/A.

It is often necessary to add some Permit or another broadleaf product to RiceStar HT when applied pre-flood. I am OK with most tank-mixtures, however, the liquid Aim formulation has caused some problems it terms of antagonizing grass control with RiceStar HT. The new product Broadhead (quinclorc + Aim premix) contains a DG formulation of Aim. We are looking at this one this year to test for antagonism. We have reason to believe it will not be as antagonistic as the liquid form.

Another preflood option that I turn to a lot on bigger grass is Regiment. Since we discovered what a little UAN can do in an adjuvant like Dyne-A-PAK, Regiment has become a much more consistent option for Barnyardgrass. It also controls a host of broadleaves. It weakness at this timing is a lack of control of all other grass weeds.

I left out a bunch of stuff, for many propanil or propanil combinations with other products work great. I usually don’t get calls about these fields. There are many other options for broadleaves and stradegies for grass, can’t cover them all here.

Tuesday, May 18, 2010

May 17 Rice Condition and Progress

The weather this spring has allowed rice to be planted across most of the state at record pace. As of May 16, farmers had planted an estimated 97% of the rice acreage. This compares to 95% last week and only 68% this time last year. It is also well ahead of the 5-year average of 84% for this week. The USDA estimates that 90% of the rice acreage has emerged. This compares to 55% last year at this time and 69% for the 5-year average. Our planting progress is 2-3 weeks ahead of the 5-year average and a month ahead of last year. As of May 16, 14% of the crop is reported to be in excellent condition, 53% good, 29% fair, and 4% poor.

Average temperatures were near normal ranging from 1 degrees below normal at Newport to 7 degrees above normal at Monticello for the week ending May 16. Low temperatures ranged from 43 degrees at Marianna to a high of 92 degrees at Stuttgart. Rainfall for the week ending May 16 ranged from a low of 0.08 inches at Warren to a high of 4.2 inches at Fayetteville. Overall, soil moisture supplies were 13% short, 56% adequate, and 31% surplus.

Much of the rice is reaching the stage for flood establishment and several thousand acres have already been flooded. Remember to wait until the soil dries to apply preflood nitrogen fertilizer and then apply a shallow flood as quickly as possible.

Very early estimates suggest that CL 151 is the most widely planted variety so far (about 23% of the acreage). The next most widely planted varieties are Wells (16%), Rice Tec CL XL 745 (16%) and Jupiter (12%). These numbers are preliminary and may change as we get more information available.

Tuesday, May 11, 2010

MANAGING FOR STRAIGHTHEAD STARTS EARLY

It seems the flood has just been established and now it is time to drain and dry the field for straighthead control.

Straighthead is one of the oldest reported rice diseases in Arkansas, observed since the early 1900s when rice was first grown, and was especially a problem on newly cleared rice ground and lighter soil types. It has historically been associated with old cotton fields, where arsenical pesticides were once used, and arsenic has been shown to produce straighthead symptoms, however arsenic is apparently not the only cause of the problem.


Fields that favor straighthead are permanent, that is, each time rice is planted, straighthead will develop at some level if the flood is not drained and the soil aerated at the appropriate time. Historically, it is unlikely to observe straighthead on clay soils.

Straighthead symptoms include darker green plants in the paddies, followed by blanked or blanked and distorted panicles (See photo above). Medium and short grain varieties tend to have the most kernel distortion symptoms while many modern long grain varieties mostly blank out, without much noticeable distortion. Glyphosate drift during midseason can result in heavily distorted or partially blanked panicles that can be confused with straighthead. However, glyphosate injury usually affects the upper developing leaves, especially the flag leaf size, shape and texture, and can be observed in paddy rice and on levee rice. Straighthead does not noticeably affect anything except the panicle on rice and only occurs in flooded paddies. Note the photo below illustrates the deformed kernels but also a stunted flag leaf, indicative of herbicide injury.

Straighthead is a serious disease with yield losses approaching 100% if a highly susceptible variety is planted on a severe straighthead soil and not drained and dried prior to panicle initiation. Each year, we list the straighthead reactions of most varieties grown in Arkansas in the annual Rice ARPT report, available through the local County Extension office or on the Internet at http://arkansasvarietytesting.org.

If a susceptible variety is mistakenly planted on a straighthead field, the disease can be prevented by “draining and drying”. Typically, this has to be done after the field has been permanently flooded but completed before internode elongation starts. The best way to time draining and drying is by using the University of Arkansas DD50 Program, available through the County Extension Office or on the Internet at http://dd50.uaex.edu/dd50Logon.asp . This program will predict the best straighthead drain period for each field entered. If draining and drying is done improperly, you may not get the best straighthead control, or you may hurt rice yields by drying too long. 

Some growers worry that draining and drying will increase the chance of neck blast developing later. While this may be true in some circumstances, it is not a certainty, and straighthead damage is much more certain on fields with straighthead history. In order to avoid this conundrum, plant varieties that are less susceptible in known straighthead fields. If you mess up and plant a blast susceptible type, you must still drain and dry, then flood as deep as possible afterwards to minimize blast.

Monday, May 10, 2010

May 10 Rice Crop Condition

The weather this spring has allowed rice to be planted across most of the state at record pace. As of May 9, farmers had planted an estimated 95% of the rice acreage. This compares to 90% last week and only 66% this time last year. It is also well ahead of the 5-year average of 79% for this week. The USDA estimates that 82% of the rice acreage has emerged. This compares to 46% last year at this time and 57% for the 5-year average. Our planting progress is 2-3 weeks ahead of the 5-year average and a month ahead of last year. As of May 9, 16% of the crop is reported to be in excellent condition, 45% good, 35% fair, and 4% poor.

Average temperatures were near normal ranging from 2 degrees below normal at Gibert to 6 degrees above normal at Eudora for the week ending May 9. Low temperatures ranged from 39 degrees at Fayetteville to a high of 92 degrees at Stuttgart, Rohwer, and Eudora. Rainfall for the week ending May 9 ranged from a low of 0.02 inches at Eudora to a high of 2.1 inches at Morrilton. Overall, soil moisture supplies were 18% short, 67% adequate, and 15% surplus.

The water is still receding from the flooding that occurred last week. It is still unknown at this time how much of that rice will need to be replanted. Much of the rice is reaching the statge for flood establishment. Remember to wait until the soil dries to apply preflood nitrogen fertilizer and then apply a shallow flood as quickly as possible.

Very early estimates suggest that CL 151 is the most widely planted variety so far (about 24% of the acreage). The next most widely planted varieties are Wells (15%), Rice Tec CL XL 745 (14%) and Jupiter (13%). These numbers are preliminary and may change as we get more information available.

Tuesday, May 4, 2010

PREFLOOD NITROGEN TIME - ALREADY?

It’s only the first week of May and the earliest fields are now approaching time for preflood fertilizer. The rain can create some problems for growers as it becomes time for preflood fertilizer but we have experienced good drying conditions between rains so far this spring. Urea should be applied to rice onto dry soil prior to establishing the permanent flood. Agrotain should be used with the urea to reduce volatilization losses unless the field can be flooded in less than 2 days.


If the fields are wet when the preflood urea needs to be applied, the best option is to wait until the soil dries. A delay of up to 10 days after the last DD50 recommended date is better than applying the urea into muddy soil or directly into the floodwater. If it becomes necessary to apply the urea to muddy soil, apply Agrotain-treated urea to the soil and flood up as soon as possible. The least effective method of applying preflood nitrogen is directly into the flood, even if Agrotain is used. While several growers have made excellent rice by spoon-feeding into the flood, this is the least efficient method and generally requires more urea to maximize yields. The recommended fertilizer rates and timings for the most commonly available rice varieties in Arkansas are listed below.

These recommended rates are for rice following soybeans in rotation. For other rotations, consider the following:
1. Increase early N rate by 30 lbs/A if rice is grown on clay soils.
2. Increase early N rate by 20 lbs/A if:  i) rice follows RICE in rotation or ii) the stand density if < 10 plants per sq. ft.
3. Increase early N rate by 10 lbs/A if rice follows GRAIN SORGHUM, WHEAT, CORN, or COTTON in rotation
4. Decrease early N rate by 10 lbs/A if rice follows SETASIDE or FALLOW that is not continuously tilled in rotation
5. Omit early N rate if rice follows FISH, LONG-TERM PATURE, or FIRST YEAR AFTER CLEARING in rotation.

Management of preflood nitrogen is most important for determining overall yield potential.  If this application is not managed as well as possible, it is very difficult to make up for the mistake at midseason.

May 6 Rice Crop Conditions

CROP CONDITION AND STATUS – The weather this spring has allowed rice to be planted across most of the state at record pace. As of May 2, farmers had planted an estimated 90% of the rice acreage. This compares to 81% last week and only 60% this time last year. It is also well ahead of the 5-year average of 70% for this week. The USDA estimates that 61% of the rice acreage has emerged. This compares to 27% last year at this time and 39% for the 5-year average. Our planting progress is 2-3 weeks ahead of the 5-year average and a month ahead of last year. As of May 2, 16% of the crop is reported to be in excellent condition, 45% good, 35% fair, and 4% poor.

Severe storms and rainfall pounded the rice-growing region of Arkansas over the weekend. Rainfall over the weekend ranged from as little as 0.25 inches in Southeast Arkansas to as much as 11 inches in parts of Northeast Arkansas. Levees are washed out and floods are as much as 8-10 feet deep in some fields in river bottom lowlands. Time will tell the impact this has on the crop and the need for re-planting.

Average temperatures were near normal ranging from 5 degrees below normal at Booneville to 2 degrees above normal at several locations for the week ending May 2. Low temperatures ranged from 35 degrees at Fayetteville to a high of 89 degrees at Camden and El Dorado. Rainfall for the week ending May 2 ranged from a low of 0.1 inches at Fort Smith to a high of 8.4 inches at West Memphis. Overall, soil moisture supplies were 7% short, 69% adequate, and 24% surplus.

The USDA planting intentions report that was released at the end of March shows that rice acreage is expected to increase by 10% from 2009. The anticipated acreage of 1.631 million acres is the largest acreage since 2005 when we planted an estimated record 1.635 million acres. Medium grain rice for Arkansas is estimated at 200,000 acres, a decrease of 60,000 acres from 2009.

Tuesday, April 27, 2010

Rice DD50 Program Online and Ready!

The 2010 version of the Arkansas Rice DD50 Program is up and running. Five new varieties have been added to the program. for 2010. The program can be accessed through the county Extension office or online at: http://dd50.uaex.edu/dd50Logon.asp. In order to enroll, you need the variety name, the emergence date, and the number of acres. The program will predict the timing of approximately 27 different production practices. This allows growers and consultants to be more efficient in scouting the crop and more timely with treatments. On-time decisions can often be the difference between success and failure.

April 26 Rice Crop Condition

The weather this spring has allowed rice to be planted across most of the state at record pace. As of April 25, farmers had planted an estimated 81% of the rice acreage. This compares to only 53% last week and only 42% this time last year. It is also well ahead of the 5-year average of 53% for this week. The USDA estimates that 43% of the rice acreage has emerged. This compares to 10% last year at this time and and 19% for the 5-year average. We have more rice emerged this week than we had planted in 2009. We have 80% of the rice planted prior to April 25 and with another good week, we are likely to be 95% complete before the first of May. Our planting progress is 2 weeks ahead of the 5-year average and a month ahead of last year.

Getting the crop planted early is certainly good for production. However, with nearly a million acres planted in a 2-week window, harvest is certainly going to be interesting. We are set up for an excellent crop, assuming the summer and fall weather are not too unkind.
Average temperatures were near normal ranging from 3 degrees below normal at Booneville to 9 degrees above normal at West Memphis for the week ending April 25. Low temperatures ranged from 36 degrees at Calico Rock to a high of 88 degrees at West Memphis. Rainfall for the week ending April 25 ranged from a low of 0.3 inches at Brinkley to a high of 4.4 inches at Batesville. Overall, soil moisture supplies were 1% very short, 17% short, 67% adequate, and 15% surplus.

The USDA planting intentions report that was released at the end of March shows that rice acreage is expected to increase by 10% from 2009. The anticipated acreage of 1.631 million acres is the largest acreage since 2005 when we planted an estimated record 1.635 million acres. Medium grain rice for Arkansas is estimated at 200,000 acres, a decrease of 60,000 acres from 2009.

Thursday, April 22, 2010

Roy J - New Rice Variety Released in 2010

The University of Arkansas released a new variety this winter that should provide growers a new alternative to Wells that have improved yield potential and improved straw strength. Based on various trials, the yield potential of Roy J appears to be substantially better than Wells and Francis. The overall disease reaction is similar to Wells. It is susceptible to rice blast but appears to be slightly better than Wells. It is about 43 inches tall but has the strongest straw strength of any variety that tall I have every seen. In three years of testing, I can count on one hand how many plots have lodged. Roy J was distributed as Foundation seed this spring. Registered seed should be available for purchase in 2011.

Wednesday, April 21, 2010

Calculating Rice Seeding Rates

After variety selection and preplant fertilizer, the next decision that should be made is seeding rate. The recommended seeding rate for drill-seeding most varieties is 30 seeds per square foot to achieve a stand of 15 to 20 plants per square foot. Since the seed size differs among varieties, the actual seeding rate in pounds per acre varies by variety. An Extension publication, “RICESEED” (Rice Information Sheet No. 163), is available to help calculate seeding rates for specific varieties and is also available in a computer program available on the Cooperative Extension Service website.

In addition to calculating seeding rates for specific varieties, these resources also assist in making adjustments for soil types, planting dates, planting systems, seedbed condition, etc. The computer version can be found at: http://riceseed.uaex.edu.

The program can also assist in calibrating drills by giving the number of seed required per row foot, depending on row spacing, to achieve a given seeding rate. For example, seeding rates of 30 seeds per square foot translates to 73 lbs/acre for Wells and a drill on 7.5 inch spacing should plant 19 seeds per row foot.

Optimum Rice Planting Window Still Open

Our recommended seeding dates for Arkansas begin as early as March 25 for South Arkansas and April 1 for Central and North Arkansas. The optimum planting date window is April 1 to May 20 for South Arkansas and April 10 to May 10 for North Arkansas. We have been fortunate to get a lot of rice planted early, in contrast to the last two years. With over half of the crop planted before April 20, farmers have positioned themselves for a good crop.

The remaining rice to be planted is likely to be spread over the next 6 weeks for various reasons. The optimum window is still open for most varities and will remain until about May 10 to May 20. After the calendar moves past that date, the yield potential declines dramatically. By the time rice planting is completed in June, the yield potential may have been reduced by as much as 30-40%.

April 20 Arkansas Rice Situation

The weather this spring has allowed rice to be planted across most of the state. As of April 19, farmers had planted an estimated 53% of the rice acreage. This compares to only 19% last week and only 23% this time last year. It is also well ahead of the 5-year average of 30% for this week. The USDA estimates that 16% of the rice acreage has emerged. This compares to 3% last year at this time and and 7% for the 5-year average. Rice farmers in Arkansas demonstrated just how much rice they can plant in week when the weather cooperates. A third of the rice acres (~500,000 acres) was planted last week.

Average temperatures were 1 to 11 degrees above normal for the week ending April 19. Rainfall for the week ending April 19 ranged from a low of none at several locations to a high of 0.5 inches at Mena. Overall, soil moisture supplies were 1% very short, 26% short, 67% adequate, and 6% surplus.

The USDA planting intentions report that was released at the end of March shows that rice acreage is expected to increase by 10% from 2009. The anticipated acreage of 1.631 million acres is the largest acreage since 2005 when we planted an estimated record 1.635 million acres. Medium grain rice for Arkansas is estimated at 200,000 acres, a decrease of 60,000 acres from 2009.