More than 535 agriculture industry professionals made the trip to Stuttgart, Ark., to hear about the University of Arkansas System Division of Agriculture’s latest discoveries and recommendations laid out at the 2018 Rice Field Day.
The field day was held Aug. 3 at the Rice Research and Extension Center. Division faculty covered weed control, insect pests, fertility, cover crops and a growing season overview.
““It was good to host the field day back at the Station this year,” said Bob Scott, center director. “This year we went for something very farmer- or consultant-oriented and I am very pleased at how it turned out.”
“It was also nice to show off our new Foundation Seed Facility at lunch,” he said. “We just completed our second season with it and it’s working great.”
Jason Norsworthy, weed scientist for the Division of Agriculture, began with one of growers’ biggest struggles in 2018: grassy weeds.
“This year has been one of the grassiest crops I’ve seen in a long time,” Norsworthy said. “A large portion of that is because April and May were extremely dry and we struggled to get our pre-emergence herbicides activated.
Although weed control is tough without rain to activate certain herbicides, Norsworthy reminded attendees of the importance of overlapping residual herbicide applications.
“We need to treat rice as we do soybeans as far as overlaying residual herbicides,” he said. “It is much easier to kill weeds before they come out of the ground.”
Norsworthy ended with a few reminders for consultants, growers and county agents who are planning to send in weeds for resistance screening.
“If you send me samples for screening and I have not contacted you within 10 days, I did not receive your sample,” Norsworthy said. “I need 10-15 seed heads to screen and samples have to be mature.”
Samples sent to Norsworthy for resistance screening must be sent by Nov. 1. Any samples sent later will not be screened before the 2019 growing season.
Nick Bateman, rice entomologist for the Division of Agriculture, kicked off his talk with a PSA on the importance of seed treatments for control of grape colaspis and rice water weevils.
“Seed treatments are extremely valuable,” Bateman said “They’re like an insurance policy. And with 10 years of trials, we’ve seen an 80 percent chance of return on investment for seed treatments in rice.”
Bateman said when choosing a seed treatment, it’s important that growers know their field and know which pest they need to control in order to choose the most effective seed treatment.
NipsIt from Valent and CruiserMaxx from Syngenta are neonicotinoids that offer control for both rice water weevil and grape colaspis, but only last 28 to 35 days. Dermacor from DuPont lasts 80 to 100 days and is great for control for rice water weevils, but gives no protection against grape colaspis.
Aaron Cato, PhD candidate in the University of Arkansas entomology department, presented his research on refining the go to “hard dough, let it go” threshold, meaning once a field hits hard dough, growers should stop treating for rice stink bugs.
“In the past we’ve followed the expression ‘hard dough, let it go,’” Cato said. “But to give consultants and growers a more clear-cut threshold, we’re grading panicles for different stages of hard dough based on the number of straw colored kernels present. Now we’re trying to see at which stage in hard dough rice stink bugs cause appreciable levels of peck.
Cato updated attendees on the thresholds for rice stink bugs in Arkansas rice.
“We have two thresholds for rice stink bug control,” Cato said. “From 75 percent emergence, flowering and into the milk stage, our threshold is five stink bugs per 10 sweeps. From soft dough up to 60 percent hard dough, our threshold is 10 stink bugs per 10 sweeps.”
Making the best of GreenSeeker
Trent Roberts, soil fertility specialist for the Division of Agriculture, explained how to get the most accurate nitrogen readings using GreenSeeker Handheld, a device that reads and recommends nitrogen levels in rice.
“Measurements must be taken where you have adequate plant stands,” Roberts said. “If the light hits the water, it never reflects back and gives you a reading of zero and will tell you to apply more nitrogen to fix that problem, which unfortunately more nitrogen won’t fix.”
Because water does not reflect the light of the GreenSeeker back, samplers should watch out for heavy dew.
“Water drops from heavy dew can absorb the light and significantly reduces the reading as well,” Roberts said. “If you’re using GreenSeeker when there is heavy dew you need to take all of your readings before the dew burns off, or your readings can change and increase as the canopy dries out. Readings must be taken either all with dew or all without dew.”
Jarrod Hardke, rice agronomist for the Division of Agriculture, said GreenSeeker is incredibly helpful when determining mid-season nitrogen applications.
“We strongly recommend using GreenSeeker technology for mid-season nitrogen timing,” Hardke said, “However, once the flag leaf is out you should stop using GreenSeeker to determine nitrogen levels.”
Cover crops in rice
Roberts also gave rice producers an update on his current research with cover crops.
“The use of cover crops in rice production is one thing we know the least about because there are very few rice producing states,” Roberts said. “But, there are many benefits with cover crops in any cropping system.”
Planning is an important first step for success with cover crops. Producers must plan which crop to plant and plan a termination method.
“You should plan for cover crops as rigorously as you do for cash crops,” Roberts said. “If we grow a cereal cash crop, we want to move away from cereal cover crops and consider winter legumes. But whatever you plant, be sure you have a termination plan.”
Overview of the 2018 growing season
The hot, dry weather this season seems to be a theme when talking about this year’s crop, and Hardke’s recap of this season was no exception.
“We had the coldest April followed by the hottest May,” Hardke said. “The hot, dry weather has been one of the greatest struggles this year.”
Despite the rough weather, Arkansas rice seems to be pulling through.
“Overall, the rice looks very good. We expect some very good yields,” Hardke said. “But, with the amount of grass in fields, timely harvest is going to be critical this year.”
Commercial product names mentioned do not imply endorsement by the University of Arkansas System Division of Agriculture.