Arkansas Rice Update 8-11-23

by Jarrod Hardke, Rice Extension Agronomist - August 11, 2023

Arkansas Rice Update 2023-21

August 11, 2023

Jarrod Hardke, Tommy Butts, & Tom Barber

“So get ready, so get ready.”

Combines Moving

A creeping start to harvest has begun in the state (first report was last Friday, 8/4).  Very few field reports so far, but the limited numbers sound good.  The mixed bag of weather has played a role is slowing down everything.  The predictions for rainfall were true this week, and then some.

Scattered throughout the week, different areas of the state received anywhere from a few inches all the way up to 7 inches of rainfall.  Some lodging has been reported in the southeast corner of the state following heavy rain and wind early in the week.  Mid-week, heavy rains have rice getting a “melty” look after large rains, but so far they’re holding up.

Upcoming weather is expected to be up and down for temperatures, but with little to no rain.  This could be a really good week for more getting harvest underway as well as finishing up rice that is being drained or trying to mature out.  We were fortunate this week to see a nice breakup of overnight temperatures, and the coming week shows signs of those concerns fading away.

Stink bug numbers continue to come in low to moderate overall.  However, as more fields mature, those that are further behind will become greater sinks so watch out for increasing numbers in those greener fields.

The first FSA Acreage report was released today as well.  More details are below, but Arkansas has clocked in at over 1.4 million total acres planted (1.21 million long grain and ~200,000 medium grain).

Let us know if we can help.

Fig. 1.  NOAA 7-day precipitation forecast.

New on Arkansas Row Crops Radio this week:

Entomology Update 8-11-23: Stink Bugs, Insecticide Termination Timings and Salt Marsh Caterpillars

FSA Crop Acreage:

On Friday (8/11), USDA’s Farm Service Agency released its August Crop Acreage file.  As always, there is a lot to digest in this information.  Focusing on Arkansas, growers have reported 1,212,110 planted acres of long-grain (compared to 993,340 in 2022).  Planted acres do not include failed acres or prevented planting.  Medium and short grain acres reported to FSA were 199,657 acres (compared to 89,786 in 2022).  Total rice acres currently stand at 1,411,768.

Table 1.  2023 Arkansas Rice Acres.

The following table includes total rice acreage by county.  As of August 11, rice acreage had been certified in 40 counties.  The top 20 counties grow 91% of the total acres.

Table 2.  Arkansas Rice Acres* Reported to FSA, August 11, 2023.

Table 3.  2023 U.S. Rice Acres.

The August report is the first of five (5) updates to FSA’s acreage information.  Scheduled releases of FSA’s acreage reports are as follows:

• Sep 12
• Oct 12
• Nov 9
• Dec 8
• Jan 2023 TBD

Data for all crops, states, and counties are reported in the following categories: planted; prevented planting; and failed. The August dataset is available at this link 2023 acreage data as of August 11, 2023 .

Keep Late Season Herbicides Off Rice

Jarrod Hardke and Tommy Butts

With some late-planted soybeans out there, combined with other crops approaching harvest, there have been and will be some late herbicide applications.  We have seen some late drift of glufosinate (Liberty) and glyphosate (Roundup) onto rice.  It’s the glyphosate we’re most worried about in this scenario, but if heads are out glufosinate can potentially cause more trouble.  Clethodim (Select) may also be going out and one we need to keep off rice.

There is no safe time to allow glyphosate to get onto rice.  If rice is still developing in any way, it has the potential to be stopped right in its tracks when glyphosate hits it.  Certainly, this is rate and timing and growth stage dependent, but it is a real risk and often difficult to diagnose later.  Keep the glyphosate away.

Harvest Aid Tips

Jarrod Hardke

Using a harvest (sodium chlorate; salt) can be a useful tool at harvest.  Much like a hammer, it’s good when used correctly, and hurts when you don’t.

DO complete rice harvest in 5 days or less after application of sodium chlorate.  Waiting longer can allow heavy dews and/or rain events to cause milling issues.  If the panicle itself becomes too dry we can see an increase in shattered grain.

DO NOT use sodium chlorate on fields with uneven maturity.

DO NOT salt varieties until grain moisture is below 25% (e.g. Diamond, CLL16).

DO NOT salt hybrids until grain moisture is below 23% (e.g. XP753, RT 7521 FP).

DO NOT salt rice after grain moisture falls below 18%.  For long grains, there is not always a clear penalty below 18% but for medium grains it can be very harmful.  If attempting to salt a long grain at or below 18%, harvest should begin the following day.

DO consider using a lower rate of sodium chlorate if salting rice at lower moistures.  We have not observed a major difference between 3-5 lb rates of sodium chlorate, but the risk associated with using higher rates worsens as grain moisture gets low.

DO NOT salt rice solely on the basis of rapidly lowering grain moisture and expect a major moisture drop.  In research trials, salted plots have typically been only 2% lower grain moisture than the untreated check when harvested the same day.  This was true whether harvested 3 or 7 days after application.

Fig. 2.  Research plots receiving sodium chlorate (right) versus untreated check.

Harvest Aids in Downed Rice – NOPE

Jarrod Hardke

Storms moving through the state this week have resulted in some lodging of rice that was ready for harvest.  There can be a desire to use sodium chlorate on this rice to make it easier to get the combine through.  Just say no to that.

When sodium chlorate (salt) is applied, it only dries out what it contacts.  This means that in downed rice, only the upper layer of rice gets salted, and everything underneath doesn’t (Fig. XX).  Now we end up with very dry plants with drier grain more capable of shattering on top, and wetter greener plants with higher moisture grain beneath it.  This is a bad recipe.

Fig. 3.  Lodged rice (left); top layer of rice versus underneath layer after salting (right).

Fall Applied Residuals

Tommy Butts and Tom Barber

We’ve made a strong push over the past couple of years to apply residuals in the fall to combat some of our problematic winter annual weeds, particularly Italian ryegrass (Fig. 4).  We’ve seen some great results with this approach to help reduce the densities we’re battling in the spring and alleviates some pressure we’ve placed on postemergence options like clethodim and paraquat.  Unfortunately, two things we need to pay close attention to with these applications are label approvals and plant-back intervals.

Fall applications on herbicide labels are relatively few and far between.  Things like Dual Magnum, Boundary, Zidua, Anthem Flex, Command (I’m sure I’m missing a couple more) are all approved and labeled options for fall residual control of weeds.  However, outside of those, most other herbicides do not hold a fall-applied label or do not contain any language directly pertaining to fall applications.  In these instances, it becomes a gray area on legality.  Although applying a herbicide that does not contain language on the label for a fall application may not be “illegal”, it likely would fall outside of an approved use and would result in a “use at your own risk” scenario.  Therefore, we highly recommend only using products that contain specific fall application language on the label.  Additionally, we must pay close attention to the approved rates and how those rates are factored into our seasonal use or 12-month use limits.  Most fall applications count against our seasonal use limits, and therefore, we have a reduced total amount that could be used in-crop.

Plant-back intervals are the next critical piece to make note of when making a fall application decision.  These plant-back intervals are established to minimize the potential for injury on our crop the following year.  When specifically focusing on rice, the only herbicide that has a fall application label, is effective for ryegrass, and can have rice planted the following spring is Command.  Research has shown that when other herbicides are used in the fall, significant injury and stand loss can occur the following spring.  On the plus side, Command has been shown to be an extremely effective tool at managing winter weeds, particularly Italian ryegrass (Fig. 5).

Overall, fall herbicide applications are an extremely effective tool for weed management, but we need to lookout for label requirements and plant-back intervals to be the most successful.  If you have any questions on this, please don’t hesitate to reach out to us. Good luck out there!

For more information on fall weed control, particularly ryegrass management, please see our following resources:

1. Weeds AR Wild podcast from 2022 found here: https://bit.ly/2022WeedsARWildRyegrass

2. FSA 2191 Management of Italian Ryegrass in Agronomic Crops found here: https://bit.ly/RyegrassFactSheet

Fig. 4.  Ryegrass in a rice field.

Fig. 5.  Residual control of ryegrass following fall applications of Prowl and Command.

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.