Meanwhile, deep tillage left just 18% of them on the soil surface. In 2020, Dr. Lynn Sosnoskie of Cornell University will be launching herbicide resistance screening for agricultural weeds including waterhemp and Palmer amaranth in 2020; find the details in her What’s Cropping up article from March 2020. All https://www.barchart.com/solutions/ is provided by Barchart Solutions. With the increasing prevalence of Acetolactate synthase (ALS)-inhibitor and Glyphosate-resistant Palmer amaranth and kochia in Nebraska dry bean acres, dry bean growers have few herbicide options for controlling weeds within dry bean crops. “Cleaning up and blowing out combines after harvesting infested fields can prevent the spread of Palmer amaranth.”. A native of the American southwest, Palmer amaranth is more competitive than common waterhemp (Amaranthus tuberculatus), a pigweed native to Iowa. TAGS: Herbicide Resistance Management residuals Palmer amaranth This year’s online Milan No-Till Field Day gave speakers an opportunity to showcase different herbicides and combinations of herbicide treatments at growth stages that normally would not be available at a single tour stop. Indestructible? amaranth isn’t part of the mix. Palmer amaranth is dioecious, meaning its male and female flowers grow on separate plants. It (listing it) would have saved a lot of trouble in Iowa.”. Once buried, seeds die after four to five years, says Kevin Bradley, University of Missouri Extension weed specialist. Glyphosate-resistant Palmer amaranth is wide-spread across the Coastal … One thing you can say about Palmer amaranth: It’s not a member of the old boys’ club. You should be. Palmer amaranth closely resembles other pigweed species like waterhemp, particularly in the seed, seedling, and even vegetative stages. “Combines are great spreaders,” says Johnson. Palmer Amaranth: Bedeviling Farmers Like No Other Weed. It also germinates nearly the entire growing season, from early May into mid-August, says Weber. “Cash rental rates decreased, making CRP more appealing,” says Meaghan Anderson, ISU Extension field agronomist. Additional research will focus on the implications of concentrating weed seeds rather than spreading them across the width of the field. Its life-cycle is adapted to desert conditions; it will germinate and grow to quickly produce abundant seed when water is available. Still, be wary, especially if you have problem fields with waves of waterhemp. 1. iv If a Palmer amaranth plant is herbicide-resistant, it becomes even more important to make sure it is controlled before producing seeds. Palmer amaranth (A. palmeri) is an even more recent addition to New York farmers’ problems; it has been found in Seneca, Wayne and Steuben counties. “One landowner had Palmer amaranth that looked like cedar trees every 50 feet or so,” says Hartzler. Management of herbicide-resistant waterhemp and Palmer amaranth can be difficult in conventional systems, often requiring both pre- and post-emergence herbicide applications. Pigweed seeds are very small, and only very thorough cleaning of equipment used in fields with pigweed seeds present will prevent its spread to new fields. Deep tillage that buries seeds 4 to 6 inches deep ensures they won’t germinate. However, the DNA test will only be available on a limited basis for 2017. “Minnesota is likely to reap large dividends by minimizing the future establishment, spread, and economic impact of the weed. Rapid growth makes timely post-emergence herbicide applications crucial. Some Palmer amaranth will survive, but it hopefully will reduce seed production in the field.”. There are both chemical and cultural strategies farmers may use to keep it in check. Palmer amaranth is dioecious, meaning the male and female plants are separate. “Mowing is not always effective,” says ISU’s Bob Hartzler. In CRP and pollinator mixes, mowing and hand-roguing are options. The test did find weed seeds, one of which – quackgrass – is a noxious weed in Iowa. For non-conventional farmers, there is information on cover crops for weed management provided by Practical Farmers of Iowa: https://practicalfarmers.org/2019/02/taming-the-waterhemp-beast/ . In fields suspected or confirmed to have glyphosate-resistant Palmer amaranth, here’s what University of Illinois’ Aaron Hager advises: “Too many soybeans are managed under the H.O.S system – herbicide-only system,” says Bayer CropScience’s Mike Weber. For more identification and management information, try some of these resources: If you have a disability and are having trouble accessing information on this website or need materials in an alternate format, contact web-accessibility@cornell.edu for assistance. Neither is easy. Palmer amaranth is considered a threat most specifically to the production of cotton and soybean crops in the southern United States. This can look different for various crops, so let’s talk about what it takes to combat these resistance issues, specifically in corn. When the plant first emerges, the cotyledons are longer and narrower than those of waterhemp. These species have grown in New York for a long time, and have similar emergence timing and management. No Palmer amaranth is … 1. Weather conditions in 2019 likely led to a faster breakdown of residual activity from applied PRE herbicides compared to 2020, resulting in Palmer amaranth emerging after the V1 growth stage. Swiping souls? In a blog last week, I suggested to start increasing rates of residual herbicides that control Palmer amaranth, particularly in soybean. Palmer Amaranth Control in Soybeans . Take Action again has a solid identification and soybean management page for Palmer as well as waterhemp: http://iwilltakeaction.com/weed/palmer-amaranth. A week later, an Iowa crop consultant found it in a bird habitat seeding for waterways. Palmer amaranth is an annual plant native to the arid southwestern United States and northwestern Mexico. Futures: at least 10 minute delayed. If Palmer amaranth escapes, though, it’s a way to push the reset button and start from scratch with a Palmer amaranth management program. When the plant first emerges, the cotyledons are more egg-shaped than other pigweeds. Information is provided 'as is' and solely for informational purposes, not for trading purposes or advice. – Bob Hartzler. Palmer amaranth may grow up to 10 feet tall. “We will have some permanent infestations because of that.”. This herbicide-resistant, problematic pigweed emerges throughout the summer, making treatment difficult and development of herbicide resistance more likely. Water hemp and Palmer amaranth, however, are very different; both are relatively new to New York, emerge all summer long, and have significant herbicide resistance. Farmers can also bury bad memories of a Palmer amaranth infestation by burying it via tillage. In a University of Missouri study, no-till left 95% of pigweed seeds like Palmer amaranth and waterhemp on the surface. Granted, tillage can erase all the benefits that reduced tillage or no-till bring. “Palmer seems to have a better will to survive than any other weed,” says ISU’s Bob Hartzler. Conservation seedings contaminated with Palmer amaranth seeds joined fields contaminated by traditional farming practices to the point where 49 of Iowa’s 99 counties now have confirmed Palmer amaranth infestations. Alan York, Professor Emeritus . Palmer amaranth doesn’t always sport this watermark. “At first, we thought maybe it was a fluke and that weather conditions were promoting Palmer. Be wary of feed and bedding from infested states, such as Arkansas and Tennessee. Just when you think this wicked weed has finished its season-long germination and emergence pattern, it can still poke up through a hole in a September soybean canopy. W e learned a lot in 2018 from a Kansas State University study on the evolution of glyphosate resistance in Palmer amaranth (pigweed). Herbicides applied PRE including Trivence, Optil PRO, Valor XLT, Fierce, and Authority MTZ provided 95% to 100% control of Palmer amaranth … Unfortunately, it’s not easy, particularly in early-growth stages. It will take a mix of control measures, though. This can make it easier to create biotypes that resist herbicides and enhance survival. Harvest is an opportune time for Palmer amaranth to move, too. Not so in 2016. Can grow to 6-8 feet tall 3. Palmer amaranth is a competitive and aggressive pigweed species that poses a major threat to North Dakota crop production. “That makes for lots of genetic variability,” says Bayer’s Mike Weber. Besides the DNA test, seed producers may also use a grow-out method. It was a weed – or weeds – that they hadn’t seen before: waterhemp or Palmer amaranth, also known as Palmer pigweed or simply pigweed. It has spread to a point to where there are now 49 out of 99 Iowa counties where it has been found. Often, though, it reaches just 6- to 7-foot heights, says ISU’s Bob Hartzler. “In Crawford County, one landowner had eight people work for 11 hours to pull it and then put it in a barrel afterward and burn it,” says Hartzler. That’s what farmers whose fields were contaminated by livestock feed or manure containing Palmer amaranth have experienced. At press time, a bill had been introduced in the Iowa Legislature to declare Palmer amaranth a noxious weed in Iowa. A two-day rainy spell when the weed is 4 inches high could render Liberty ineffective when a sprayer is next able to enter a field. Even with crop competition, this weed can still produce 250,000 to 500,000 seeds per plant, says Mike Weber, senior technical service representative for Bayer CropScience. A silent lurker of debauchery? Palmer is dioecious, with male and female plants; outcrossing results in rapid spread of herbicide resistance. Sure. “Postemergence herbicides that demonstrate control or suppression of Palmer amaranth include synthetic auxin herbicides (dicamba, 2,4-D), diphenylethers (acifluorfen, lactofen, fomesafen), glufosinate, glyphosate, and HPPD inhibitors (mesotrione, tembotrione, topramezone),” says Hager. Palmer amaranth arrives in multiple ways. Equally disconcerting is the migration of Palmer amaranth from conservation seedings to cropland. In a normal year, state seed producers were able to fill demand locally for seed production. Crop Science Department, North Carolina State University . “We will not spray our way out of this,” says Mike Owen, ISU Extension weed specialist. Waterhemp (A. tuberculatus) is a growing problem in New York, with two new counties added to the waterhemp map in 2019. “Everyone in agriculture will have to pay attention to what’s in the fields.”. It’s also invaded states as far north as Minnesota, Iowa, and Michigan. It’s especially scary when Palmer biotypes exist that resist multiple herbicide sites of action (SOA) like: So far, no biotypes have been found that resist the synthetic auxin/Group 4 SOA. Cultivation in combination with herbicide application can increase the overall level of control. For related content and insights from industry experts, sign up for Successful Farming newsletters. In Illinois, the Illinois Crop Improvement Association uses a grow-out method to evaluate whether Amaranthus weed seeds are indeed Palmer amarant. This allows the weed to have greater genetic diversity and to more easily develop herbicide resistance. This allows postemergence herbicides to be applied later in the season when the crop canopy will be able to reduce weed … If you can identify Palmer amaranth, you’re one step closer to controlling it in your fields. ‘We have advised farmers not to take manure from an animal operation that has used cottonseed as feed,” says Bill Johnson, Purdue University Extension weed specialist. “Identified fields are the  tip of the iceberg,” ISU’s Meaghan Anderson says. Recently, we’ve given some light to why farmers see resistance issues with waterhemp and Palmer amaranth and what that means for herbicide management plans. “To get all the grasses/forbs in it, they had to outsource and go to other states,” says Anderson. Certainly. Female Palmer amaranth has sharp bracts on its seed head that can extend up to 2 feet long or more. Liberty’s label, for example, says a 29-ounce-per-acre rate of the chemical needs to be applied by the time Palmer amaranth reaches a 4-inch height. “Some out-of-state seed appears to have come from fields infested with Palmer amaranth.”, One landowner had Palmer amaranth that looked like cedar trees every 50 feet or so. A DNA seed test is on tap for 2017. As with other SOAs, though, repeated use will stifle effectiveness, says ISU’s Bob Hartzler. In fields suspected or confirmed to have glyphosate-resistant Palmer amaranth, here’s what University of Illinois’ Aaron Hager advises: Plant a Liberty Link soybean into a weed-free seedbed either through tillage or through a preplant herbicide. https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/7/3461/files/2018/12/waterhemp-USB-fact-1zqg7dw.pdf, https://practicalfarmers.org/2019/02/taming-the-waterhemp-beast/, http://iwilltakeaction.com/weed/palmer-amaranth, Pennsylvania State university has a good pigweed identification guide, Kansas State University has another very good identification guide, University of Minnesota has a good pigweed ID guide. Palmer amaranth has dioecious reproduction, so individual plants are either male or female, which forces outcrossing and genetic diversity. Thanks to the plant’s ability to proliferate traits for herbicide resistance, those moves no longer work. Earlier in the season, though, it grows at a more manageable ½ inch per day, says ISU’s Bob Hartzler. Herbicide-Resistant Palmer amaranth in Nebraska: Palmer amaranth infestation is increasing in soybean and corn fields (Figure 1) in eastern Nebraska and several other crops such as dry bean and sugarbeet in the Nebraska Panhandle. In at least two cases, Palmer amaranth arrived on agricultural machinery purchased from the Midwest, and is now found in the first field where that machinery was used. “If you do mow, you need to mow it regularly at a 6- to 8-inch height. Palmer amaranth is listed as a "noxious weed" in Minnesota. If you’re thinking about seeding CRP, pollinator, or other conservation acres, ISU’s Bob Hartzler gives these guidelines about how to ensure palmer Palmer amaranth-infested hay also came in from Kansas and Oklahoma, he adds. Hand-roguing is more difficult. Lower corn and soybean prices compounded by excellent CRP bids spurred high demand for Iowa CRP plantings in 2016. With no surrounding crop, just one plant can produce 1 to 1.8 million seeds. “So even if it was found, it wasn’t illegal to sell it,” says Hartzler. The weed world seems eons away from the demonic one. Having explored resistance issues with waterhemp and Palmer amaranth, let's turn our attention to discuss some control options for soybean in fields where resistance has been observed. Even if a standard purity seed test found an Amaranthus species, it’s impossible to visually distinguish Palmer amaranth from the approximately 48 other such species. Herbicides with Atrazine can take control over Palmer Amaranth when it is applied to corn, at a max rate of 2.5 lb ai/A/yr if it is applied at two timings for pre-emergent control. Chaff lining concentrated 87% of the Palmer amaranth seeds leaving the back of the combine in a 12-inch band. Still, Palmer amaranth often towers over waterhemp. Data collected by Purdue University researchers show this weed can ravage yields by 78% in soybeans and 91% in corn. “It’s a weed to be concerned about, but it’s not the end of the world,” says Hartzler. Palmer amaranth was accidentally introduced to the southeastern US. Figure 1. It’s just that some likely slipped past the goalie. Spreader of evil? Though all populations of this weed are not resistant to commonly used herbicides, some populations are. Apply an effective soil-residual herbicide within 14 days of planting. Still, it has a similar dark prince (and princess, too) preying on your crops. Herbicide Group 3 (dinitroanilines), 5 (triazines), 15 (amides) and 27 (HPPD inhibitors) herbicides provide the crop a head start on Palmer amaranth. This herbicide-resistant, problematic pigweed emerges throughout the summer, making treatment difficult and development of herbicide resistance more likely. But here’s the deal. Plant a Liberty Link soybean into a weed-free seedbed either through tillage or through a preplant herbicide. Seed Heads. Chin up, though. Talk to federal agencies regarding management of Palmer amaranth in infested conservation seedings. The result is greater genetic diversity for plants to develop adaptive traits, such as herbicide resistance. Watermark. “It should be easier to manage now than it will be in 15 to 20 years.”. “Sometimes, waterhemp will look like Palmer, but it won’t have sharp bracts on its seed head.”. Small grains offer a competetive advantage compared to row crops due to early row closure that helps prevent late-season germination. The resistance profile for the Palmer amaranth populations in New York have not been studied; Dr. Sosnoskie plans to conduct that research and is looking for participating farmers. Learning to differentiate between the “regular” pigweeds, water hemp, and Palmer amaranth is critical for effective weed management. But last year was the worst.”. “Palmer can easily be overlooked because of waterhemp’s prevalence,” says Hartzler. “It’s the only weed I’ve seen that can drive a farmer out of business,” says Bill Johnson, Purdue University Extension weed specialist. It does steal yields, though. Has reduced yield up to 91 percent in corn and 79 percent in soybean 4. “CRP bids looked really good to what rented ground was going for, especially pollinator habitat that had a signing incentive payment,” she says. This scoundrel, having worked its evil through the Mid-South, is now heading full steam into the Midwest. Most of the world’s religions teach that, ultimately, good triumphs over evil. In many places, the plant has developed resistance since at least 2006 to glyphosate, a widely used broad-spectrum herbicide. 1 “We started seeing some herbicide-resistant Palmer around here about three years ago, and the number has been increasing,” says Justin Knopf, who farms with family near Gypsum, Kansas. Palmer amaranth is a fast growing weed native to the southwestern United States and northwestern Mexico, and has spread east and north. Prepared by Bob Hartzler, professor in agronomy and weed specialist with Iowa State University Extension and Outreach. The efficacy of herbicide classes depends on the resistance profile of the weeds in your field. Height. Palmer amaranth found in the the northern states is expected to be resistant to multiple herbicides, including glyphosate (Site of Action or SOA group 9) and ALS inhibitors (SOA group 2). It’s the same way with Palmer amaranth. These are the herbicide components for new dicamba-tolerant (soybeans) and 2,4-D-tolerant (corn and soybeans) systems. Palmer amaranth is a very recent arrival to New York, found in three counties as of January 2020. Palmer amaranth and waterhemp have an amazing ability to develop resistance to herbicides. Palmer amaranth and waterhemp are very competitive against most summer annual crops, but the availability of effective herbicides for corn and soybeans provide more options for chemical weed control. A single female Palmer amaranth plant will produce an average of 600,000 seeds. Tumble pigweed has a shrubby growth habit, and prostrate pigweed extends its stems parallel to the ground (this is often a sidewalk-crack rather than an agricultural weed). In the future, ask where the seed is tested and check if it is a reputable testing lab, advises ISU Extension field agronomist Meaghan Anderson. Both species are known for fast development of herbicide resistance, prolific seed production (>500,000 seeds … The ISU purity test, which cost $125, showed this was, indeed, the case. Emerges throughout the growing season 6. Waterhemp is the more common of the two herbicide-resistant, problematic pigweeds in New York, found in twelve counties as of December 2019. “Last year, an early soil warm-up started emergence (in central Iowa) in mid-April,” he says. Palmer amaranth continues to increase in severity across the crop production regions of the Southeast. It can reroot itself if pulled and tossed in a field. “Its common name,” says Aaron Hager, University of Illinois Extension weed specialist, “is Satan.”. Palmer amaranth is dioecious, meaning there are male and female plants. It can even exceed these parameters. Helena to debut Antares Complete soybean herbicide in 2021, Bayer launches Roundup PowerMAX 3 herbicide, Kyber herbicide for soybeans set for 2021 from Corteva Agriscience, Look for these soybean diseases and maladies in 2021, USDA announces changes to hemp crop insurance, ALS inhibitors/Group 2 (Pursuit, Scepter), HPPD inhibitors/Group 27 (Balance Pro, Callisto). Very prone to herbicide resistance (multiple modes of action) “It’s the only weed I’ve seen tha… Now I slide my most... read more. Wesley Everman, Weed Science Extension Specialist . The Minnesota Department of Agriculture Plant Protection Division Seed Program also supported it. Subsequent reports surfaced in CRP plantings. Palmer also does not yet resist glufosinate/Class 10 (Liberty). Palmer amaranth is a new introduction to Iowa, the herbicides described in this publication have not been evaluated for Palmer amaranth control under Iowa conditions. Palmer amaranth can grow up to 3 inches per day. It has caused substantial losses in crop yield and farm income, and a permanent increase in the cost of herbicide … Residual herbicides for grasses and small broadleaves will provide some control, but often not enough for full-season control. The DNA sequencing method differentiates Palmer amaranth from other Amaranthus weed species. The plants can also grow very quickly, up to 2.5 inches in one day. Herbicide options in dry beans are limited compared to other common row crops in Nebraska, such as corn or soybean. For this story, we submitted a weed check test for a wetlands mix (CP 23 Floodprone Mix) from a central Iowa landowner to the ISU seed testing laboratory that was labeled Palmer amaranth-free. Scout the treated field seven days after application. Meanwhile, Hartzler has seen waterhemp sport a watermark on rare occasions. Of course. This gives Palmer amaranth the ability to adapt and quickly spread herbicide resistance genes when selection pressure is applied (as when producers repeatedly apply single mode of action herbicides). New York’s common “regular” pigweeds are smooth pigweed (Amaranthus hybridus), redroot pigweed (A. retroflexus), tumble pigweed (A. albus), and prostrate pigweed (A. blitoides). “There was some flawed testing,” says ISU’s Bob Hartzler. Apply 32 ounces per acre of Liberty when Palmer amaranth is 4 inches or smaller. Prolific seed producer: Up to 1 million seeds per plant 5. They include: Besides narrowing soybean rows, Nebraska farmer Jayme Dick-Burkey and his family have used multiple mixes of cover crops. “If you grab a sharp spiky seed head, it is Palmer amaranth,” says Hartzler. One way Palmer invaded Indiana was from dairies buying cottonseed originating from mid-South states. Cultural practices play a large role, too. It is a traditional food of Native Americans including the Navajo, Pima, Yuma and Mohave. It also often has a single hair in the notched tip of the leaf, and has a geometric, poinsetta-like growth habit. “All hell broke loose last year (in Iowa),” says Bob Hartzler, Iowa State University (ISU) Extension weed specialist. In fact, we have a Palmer amaranth population in Michigan that is resistant to three herbicide sites of action, including glyphosate (Group 9), ALS-inhibiting herbicides (Group 2) (i.e, Classic, Raptor), and atrazine (Group 5). “One way it came into Indiana was through pollinator habitat seedings,” says Purdue University’s Bill Johnson. Palmer amaranth plant stems are not hairy at all, which helps differentiate it from redroot (quite hairy stem) and smooth (lightly hairy stem) pigweeds. Whatever you call the Devil, several religions describe the Evil One as nearly indestructible as he silently swipes human hearts while spawning global mayhem. Many populations of these species across the US are resistant to multiple herbicide modes of action. Weed control options in soybeans. “We have found that cover crops have been effective at holding back weeds,” he says. Waterhemp plant stems are not hairy at all, which helps differentiate it from redroot (quite hairy stem) and smooth (lightly hairy stem) pigweeds. Smooth and redroot pigweed have an upright habit like Palmer amaranth and waterhemp, but both have at least slightly hairy stems. The leaves are more diamond-shaped than other pigweeds, and their petioles (the stem attaching the leaf to the main plant stem) are longer than the leaf; these traits differentiate it from waterhemp. Palmer amaranth is an Amaranthus (pigweed) species that has become a devastating glyphosate-resistant weed problem in the South and parts of the Midwest over the past decade. Palmer’s status as a noxious weed in Minnesota gave state agencies authority and resources to immediately respond when it surfaced in conservation seed mixes in 2016, says Bob Hartzler, ISU Extension. Growers across the country are taking notice that weeds once dominant in their fields haven’t disappeared, but the likes of waterhemp and Palmer amaranth seem to be taking over. It’s difficult to clean Palmer amaranth out of the myriad native forb sizes and shapes found in these mixes. One reason is that it is a prolific seed producer. 1915 - First reported in Virginia b… Palmer amaranth is dioecious, having separate male and female plants. Yet, that’s the case in most states except Delaware, Minnesota, and Ohio. Contract violation could occur if an implemented control program alters the vegetation type specified in the contract, Hartzler says. The … Palmer amaranth is well established in mid-South states like Arkansas and Tennessee. “We will be working hard to control it.”. 1. © 2020 Meredith Corporation. The efficacy of herbicide classes depends on the resistance profile of the weeds in your field. It has been developed by the California Department of Food and Agriculture and Eurofins BioDiagnostics. Palmer Amaranth is a highly competitive pigweed species with herbicide resistant populations that are problematic in many states. All Rights Reserved. The good news is, Palmer is not yet adapted to conditions in more northern states like Iowa, says ISU’s Bob Hartzler. This isn’t always a given, though. Well, this weed may grow 10 feet tall with a circumference as thick as a baseball bat. To see all exchange delays and terms of use, please see https://www.barchart.com/solutions/terms. Palmer amaranth is a prolific seed producer. “It typically takes weeds 20 years to adapt to a new environment,” he says. This should consist of a PRE applied herbicide that is effective on Palmer amaranth overlaid with another effective herbicide POST about 14 to 20 days later. That means all parts of the plant -- both above and below ground -- must be destroyed. If you are looking for early post-emergent control in your corn field, Atrazine plus prowl or Glyphosate plus Atrazine and finally liberate 280 plus Atrazine works well. Even a weed demon can’t do everything. Consequently, weed control programs targeting Palmer amaranth need to provide season-long weed control, or weed control from planting through canopy closure. The following three factors help separate it from waterhemp. Worried? “He saw pigweed that didn’t look quite right,” says Hartzler. If control is not complete or another flush has emerged, re-treat. Last July, ISU’s Bob Hartzler fielded a call from a chemical company representative who noticed a Madison County (Iowa) field that had been planted to pollinator habitat. It’s listed as Elymus repens on the following report. Herbicide options for Palmer Amaranth is most vegetable crops are limited. Agricultural pigweeds of New York come in two categories: regular pigweeds, which are one of several closely related and largely similar species, and the two herbicide resistant problem pigweeds, waterhemp and Palmer amaranth. The leaves are glossy, longer and narrower than the other pigweeds, and their petioles (the stem attaching the leaf to the main plant stem) are shorter than the leaf. It has developed resistance to multiple classes of herbicides and their different modes of action, making it very difficult and expensive to control. The game that Palmer amaranth is changing is the old one where farmers spot weeds growing in a field, then spray a common herbicide to kill them. Meanwhile, Palmer amaranth wasn’t even considered a noxious weed with enforcement protection in Iowa, he adds. Palmer amaranth is a very recent arrival to New York, found in three counties as of January 2020. Findings like these accelerated previous discoveries in Iowa to the point where Palmer amaranth now infests 49 of Iowa’s 99 counties. Purchase locally produced native seed and communicate with those producers. “In Iowa, we now have enough Palmer amaranth that no field is safe from invasion,” says ISU Extension weeds specialist Bob Hartzler. This mimicked what happened in Ohio and Indiana in previous years. “One weed we saw last year was glyphosate-resistant Palmer amaranth,” says Jayme Dick-Burkey, who farms with his wife’s family near Dorchester, Nebraska. Waterhemp seedlings emerge throughout the summer, making them more difficult to manage with a single management practice. “There is a lack of oversight in the industry,” she says. Just don’t let it sneak up on you. A closer examination revealed Palmer amaranth. ManyPalmer amaranth populations in the US are resistant to glyphosate, and it is common for plants to be resistant to ALS-inhibitor herbicides as well. Look for a white chevron- or V-shape watermark on Palmer leaves. In 2020, Dr. Lynn Sosnoskie of Cornell University will be launching herbicide resistance screening for agricultural weeds including waterhemp and Palmer amaranth in 2020; find the details in her “What’s Cropping Up” article from March 2020. Other nonnoxious weeds found include: Not having Palmer amaranth listed as a noxious weed is akin to a priest not talking about sin in his homilies. At harvest, you may discover that weeds have escaped your control efforts and are setting seeds. Bryan Brown of NY IPM spoke to the Soybean & Small Grains Congress in winter 2020, and provided specific suggestions for the waterhemp resistance profiles he has seen so far in New York. The herbicide resistance website Take Action has management suggestions for soybean as well: https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/7/3461/files/2018/12/waterhemp-USB-fact-1zqg7dw.pdf. Reducing Palmer amaranth seed in manure; and; Field application of contaminated manure. “Look at alternative strategies of weed management.”, By welding receivers to a large section of steel pipe and adding wheels, I have saved many trips to the workbench. The formula used to calculate CRP rates uses average cash rental rates from previous years, when grain prices were higher than in 2016. Grows aggressively: Can grow 2 to 3 inches per day in optimum conditions 2. Here's why.