Arkansas Rice Update 4-21-23

by Jarrod Hardke, Rice Extension Agronomist - April 21, 2023

Arkansas Rice Update 2023-05

April 21, 2023

Jarrod Hardke and Trent Roberts

“Come in she said I’ll give ya shelter from the storm.”

Full Stop Rain

I don’t think anybody asked for THAT much rain.  Immediate reports from the Thursday night into Friday morning rain were 1.5+ inches in the northeast, 2-3 inches in central and southern, and some local amounts of over 4 inches.  As the saying goes, at some point it can’t get wetter, only deeper.

The tremendous progress so far in April looks to see a return to the mean for the upcoming week.  This event looks be followed by days of rain in the upcoming week.  Meaning it’s possible we’ve seen the last rice planted in April for the year.  Still very good yield potential for rice into early May, but the window tightens quickly.  From around May 15 on can be a wildcard in terms of remaining yield potential.

It seems like the early 1.3-million-acre estimate will be reached, and 1.4 million is on the table.  The home stretch will determine the final landing spot of course.  But considering how many have gotten to plant all the rice acres they intended (and maybe added a little more), this could be the highest “odd-numbered” year acreage since 2009.  Continued commodity price fluctuation will be another player in final acreage decisions.

Let us know if we can help.

Fig. 1.  NOAA 7-day precipitation forecast.

Last week I suspected we would be between 30-40% planted when Monday’s report was released.  By Monday prior to the report, I was convinced it was at least 40%.  By the middle of this week, it seems more like 50%+ and it just might be 60% or more.  Given the past few years, its amazing to see how many have finished planting rice or are finishing up.  Some areas are well beyond 60% planted.

So, while Monday’s report came in at 33%, to stay close to what actual progress seems to be, the report will need to reflect another substantial jump of 20%+.

Table 1. U.S. Rice Planting Progress as of April 16, 2023 (USDA-NASS).

Fig. 2.  2012-2023 Arkansas rice planting progress by week (USDA-NASS).

Fig. 3.  Flooding rains on 4/20-4/21.

Starter Fertilizers in Rice

Jarrod Hardke and Trent Roberts

Rapid planting progress and overall solid temperatures have rice on the move.  With more rice emerging, the topic of “starter” nitrogen (N) fertilizers always gets rolling.  Most often these conversations revolve around ammonium sulfate (AMS) or diammonium phosphate (DAP) or a blend of the two.  Regardless of the fertilizer type, here are some thoughts on attempting to use them in rice.

1. Do not apply starter N fertilizers at planting. Rice continues to live off the seed until around the 2-leaf stage.  Preplant, at-planting or early post-emergent applications of N can be tied up or lost before the rice has an opportunity to take it up.  If poultry litter is the source, given the amount of N and the form, there will still be N readily available to the rice.  However, surface-applied unincorporated poultry litter is more prone to loss via surface runoff during heavy rain events.

2. If applying a starter N source, the earliest it should be considered is the 2-3 leaf stage. The rice needs to have a developing root system and be ready to take it up as soon as it is incorporated when we flush or it gets rained in.

3. When applying starter N at the 2-3 leaf stage, there shouldn’t be an expectation of a yield response. Any yield response likely won’t cover the cost of the fertilizer and application ($35 or 5.2 bu at $6.75 rice).

4. On clay soils we generally expect to see a significant growth increase – usually a gain of 1-2 inches in plant height compared to no starter applied. A yield increase is still not expected, but greater plant size may assist in taking fields to flood earlier and the ability to save on a herbicide application and allow earlier harvest (a huge plus on clayey soil).  If conditions are good and rice is growing rapidly, you are much less likely to see a positive growth response and we should save the money and skip the application.

5. On silt loam soils we do not typically see much crop growth response or faster development.

6. There are conditions that can arise where we want to consider a starter N application, particularly when rice is slow growing or injured, but this decision should be made on a field-specific basis.

7. While we often refer to AMS as “sulfate”, it is not the sulfur (S) that is doing any work in this situation. Most of our rice fields on loamy or clayey textured soils will not respond to S fertilization.  Coarse (sandy) soils can respond to S, but most soils do not.

8. If you decide to apply starter N at 2-3 leaf rice, do not count any of the N toward your preflood N rate. While perhaps 5-10 lbs N could be counted, the number is going to be highly variable depending on field management from fertilizer application to flooding.  So, to maximize yield potential, act like you don’t have any extra N there.

As with many other practices, environmental conditions and many other factors will impact the potential yield response and profitability of starter N applications to rice at the 2-3 leaf stage.  Take the time to make assessments on a field-by-field basis and determine if the rice could benefit from the early season boost in growth and vigor.  Starter N applications in rice are a practice where yield increases will most likely not cover the cost of fertilization.  However, the anecdotal benefits of early season vigor and reduced time to flood are often more beneficial than we give them credit for and should be taken into consideration.

Table 1.  Rice grain yield as affected by starter nitrogen (N) application at selected growth stages for Diamond at Stuttgart, AR in 2020 on a silt loam soil.

*Starter N flushed in ~5 days after starter application, leading to rice growing beyond original stage at application for all growth stages.

**Means within the same column followed by a different letter are significantly different at α = 0.10.

Table 2.  Rice plant height 3 weeks after application as affected by starter nitrogen (N) application at selected growth stages for Diamond at Stuttgart, AR in 2020 on a silt loam soil.

*Starter N flushed in ~5 days after starter application, leading to rice growing beyond original stage at application for all growth stages.

**Means within the same column followed by a different letter are significantly different at α = 0.10.

Table 3.  Rice grain yield for clay and silt loam soil textures as affected by starter N rate at 2-leaf for Wells and Cheniere in 2005-2006 in Mississippi, Louisiana, and Missouri.

*Means within the same column followed by a different letter are significantly different at α = 0.05.

Table 3 Reference:  Walker, T.W., Bond, J.A., Ottis, B.V., and Harrell, D.L.  2008.  The effects of starter nitrogen to rice seeded at various densities.  Online.  Crop Management doi: 10.1094/CM-2008-0911-01-RS. 

Table 4.  Rice grain yield and plant height as affected by starter N source at 2-leaf for Cocodrie in 2005-2006 in Mississippi, Arkansas, and Missouri on clayey soils.

*Means within the same column followed by a different letter are significantly different at α = 0.05.

Table 4 Reference:  Walker, T., Norman, R., Ottis, B., and Bond, J.  2008.  Starter fertilizer for delayed-flood rice – agronomic effects.  Online.  Better Crops Vol. 92 No. 2.

DD50 Rice Management Program is Live

The DD50 Rice Management Program is live and ready for fields to be enrolled for the 2023 season.  All log-in and producer information has been retained from the 2022 season, so if you used the program last year you can log in just as you did last year.  Log in and enroll fields here:  https://dd50.uada.edu.

Use the Arkansas Rice Advisor Internet App!

The Arkansas Rice Advisor site https://riceadvisor.uada.edu functions like an app on your mobile device.  There you can readily access the DD50 program, rice seeding rate calculator, drill calibration, fertilizer and N rate calculators, publications, and more.

Additional Information

Arkansas Rice Updates are published periodically to provide timely information and recommendations for rice production in Arkansas.  If you would like to be added to this email list, please send your request to rice@uada.edu.

This information will also be posted to the Arkansas Row Crops blog (http://www.arkansas-crops.com/) where additional information from Extension specialists can be found.

More information on rice production, including access to all publications and reports, can be found at http://www.uaex.uada.edu/rice.

Acknowledgements

We sincerely appreciate the support for this publication provided by the rice farmers of Arkansas and administered by the Arkansas Rice Research and Promotion Board.

The authors greatly appreciate the feedback and contributions of all growers, county agents, consultants, and rice industry stakeholders.