Dr. Jarrod Hardke
March 22, 2018 No. 2018-04 www.uaex.edu/rice
Planting Time or Time to Question
A recent conversation went like this:
Grower: “Is it too early to plant 10% of my rice?”
Me: “Fire away.”
Grower: “That’s like saying sick’em to a bulldog…”
He wasn’t wrong. But I also knew where he was going to plant that rice – far southeast Arkansas (see Table 1). And as another grower asked, “do you have your crystal ball on you?” To which I replied, “right here in my shirt pocket like always.”
So I can look at the forecast as well as you can, and I’m not crazy about it. However, that’s one of the reasons to put a little rice in the ground depending on where you are in the state – the forecast could be better but it could be worse. I don’t want much in the ground but this isn’t the worst place to start. As long as you acknowledge that emergence could be slow, somewhat uneven, risk some seed treatment loss, and an extra herbicide application, but you may have really good yields, then fire away. The risk can be worth the reward if you don’t risk too much.
I reminded in the last newsletter to plant varieties first because it’s a safer approach due to hybrids holding their optimum yields later into the planting window, but there’s another bonus. If you’re going to plant really early, the initial seed cost is cheaper allowing you plant what you need, and if forced to replant that cost will be lower too.
Seeding Rate Data
Seeding rate recommendations are always fun to make. Much like the rest of farming, it all depends. Use the RICESEED Update (https://uaex.edu/farm-ranch/crops-commercial-horticulture/rice/Riceseed%20Update%202018.pdf) to help make your decisions with 30 seed/ft2 your starting baseline for loamy soils and 36 seed/ft2 for varieties; and for hybrids use 10 seed/ft2 for loamy soils and 12 seed/ft2 for clay soils. Rate adjustments based on soil conditions, planting date, and location in the state are included in the RICESEED program and in the update.
These recommendations are intended to give you the best chance for success. Can you achieve optimum yields with lower seeding rates at times? Yes. Can you achieve optimum yields with higher seeding rates at times? Yes. Can you have issues even at recommended seeding rates? Of course.
At the end of the day – I want 15 plants/ft2 with a variety and 7 plants/ft2 with a hybrid. Plant what seed you need to make that happen.
So that everything is on the table, I have attached a rundown of all the seeding rate tests we’ve done over the past few years (https://uaex.edu/farm-ranch/crops-commercial-horticulture/rice/2015-2017%20Rice%20Seeding%20Rate%20Studies.pdf). It’s a lot to look at, but it’s there for you to look over. You’ll see times where 40-50 seed/ft2 has higher yields on loamy soils, but look at the stand counts and the stand was probably weak at the 30 seed/ft2 rate. Also pay attention to what the soil type is for each study. See the above statement about ending stand – that’s most important.
All seeding rate studies receive insecticide and fungicide seed treatments. We don’t recommend going without these treatments. Use them. But if you go without them you will need to consider upping that seeding rate, especially the higher your grape colaspis and rice water weevil pressure is.
When you’re looking at the data figures – note the letters on the bars – this refers to the statistical analysis. Any two bars with the same letter on them means they aren’t significantly different – for instance if two bars have an ‘a’ on them they’re the same, or if one has an ‘a’ and one has an ‘ab’ they’re the same.
I can hear you now, “but this one treatment is 5-10 bu/acre better, I don’t care if they’re significantly different!” The reason you should care is that if they aren’t significantly different then the yield response was too variable to separate them even though the average yields may be different. This is why it’s important to look at several locations and soil types across years to get a better idea of plant stands and yields achieved at given seeding rates.
Call or email me with questions – 501-772-1714 or firstname.lastname@example.org.
Fig. 1. This seed is on his own now.
Bird Repellent an Option to Consider
For those planting rice early and in isolated situations where bird depredation of seed can be issue, AV-1011 seed treatment is something to consider. This gives the birds “digestive distress” when they try to eat the seed. They will still eat a few but it doesn’t take them long to want to leave the field. The rate to use is 18.3 oz per hundredweight (cwt) of seed. There are some rebates available for this treatment this year, but average cost per acre will be in the neighborhood of $16-18 per acre for varieties or $6-7 per acre for hybrids, depending on seeding rates. So it may not always be the way to go but for those with major concerns it’s cheaper than a replant.
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 email@example.com.
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.edu/rice.
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.