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David Moseley, Davis, Jeff A., Kerns, Dawson, Kerns, Shelly, Deliberto, Michael, Villegas, James M., Conger, Stacia
James Villegas and Dawson Kerns, Field Crop Entomologists
Figure 1. Tobacco thrips and injury on seedling cotton
Thrips are the most consistent early-season insect pest of cotton in Louisiana. Tobacco thrips are usually the dominant species, with western flower thrips sometimes present at lower levels. Thrips feed on tender, expanding leaf tissue with piercing–sucking mouthparts, causing crinkled or cupped leaves, stunting, and delayed maturity, especially when cotton is growing slowly under cool, wet, or otherwise stressful conditions. Because thrips lay eggs inside the plant tissue and immatures often feed in protected terminal, foliar sprays can be hard to time perfectly. The goal of thrips management is not to eliminate every thrips but to protect cotton during the short vulnerable window from emergence through about the 3rd–4th true leaf stage (when growth is rapid), so the crop can maintain a strong, uniform start.
Begin scouting soon after emergence and continue at least weekly (twice weekly under high risk) until cotton is past the thrips-susceptible stage. Check the terminal and the newest leaves across multiple areas of the field. A few adult thrips may simply just be migrating into the field. Immature thrips are more important because they indicate successful reproduction and a higher risk of ongoing injury. A practical action guideline is to treat when the field averages about one or more immature thrips per plant, or when large numbers of adults are present with fresh injury to new leaves on small, slow-growing cotton. Under good growing conditions, treatment is usually not needed once cotton reaches the 4th true leaf stage.
Preventive at-plant protection provides the most consistent return because thrips attack immediately and are difficult to reach with foliar sprays once injury is visible. Insecticide seed treatments (ISTs) are the most common approach, but performance can vary with weather and thrips pressure. Be aware that low-rate ‘base’ seed treatments often provide little field protection. Standard imidacloprid rates (commonly ~0.375 mg active ingredient per seed) are typically considered the minimum for reliable insect control.
In-furrow (IF) insecticides can replace or supplement ISTs and are often more effective but require additional equipment and calibration. Options include IF imidacloprid and granular aldicarb (AgLogic 15G). Aldicarb often provides excellent thrips control and may reduce the need for supplemental foliar sprays.
When at-plant protection is overwhelmed (heavy pressure) or plant growth is slowed by stress, a supplemental foliar insecticide may be needed. Applications are most effective when made early (often by the 1st–2nd true leaf stage) before severe injury accumulates. Current Louisiana recommendations include spinetoram-containing products (e.g., Intrepid Edge) because they provide good thrips control and are less likely to flare aphids or spider mites than some organophosphates. Organophosphate performance (e.g., acephate, dicrotophos) can be inconsistent in areas where reduced susceptibility or resistance has developed, so check fields after applications. In addition, Vertento® (isocycloseram) is a new product that also provides effective control of thrips.
ThryvOn is a cotton trait with activity against thrips. It primarily reduces feeding and egg-laying, so adults may still be present, but damaging injury and immatures are typically much lower. ThryvOn cotton generally does not require additional in-furrow or foliar treatments specifically for thrips. Any visible injury is usually cosmetic and not economically important. Additional at-plant insecticides may still be chosen for other pests (e.g., certain soil insects or nematodes), not for thrips.
Tobacco thrips have documented resistance to multiple insecticide classes in the southern U.S., including reduced sensitivity to some neonicotinoids and organophosphates in certain areas. To protect product performance, rotate insecticides by mode of action when multiple applications are needed, avoid repeated use of the same chemistry, and keep good spray records.
For the most current Louisiana-labeled products, rates, and precautions, consult the annual LSU AgCenter Field Crops Insect Pest Management Guide and always follow the product label. 2026 Louisiana Field Crops Insect Management Guide
Dawson Kerns and James Villegas, Field Crop Entomologists
It is going to be important to keep an eye out for corn leafhopper (CLH) in the coming months with a substantial portion of our corn acres being replanted in Louisiana. Corn leafhopper is a small, highly mobile insect that feeds on corn with piercing–sucking mouthparts. It is native to Mexico but emerged as a pest in South Texas in 2016. In 2024, outbreaks were first reported in northern Mexico before becoming widely distributed throughout Texas, Oklahoma, New Mexico, and Kansas. In 2025, infestations were mostly limited to Texas and Oklahoma, but we did detect CLH in Louisiana (Franklin Parish). This year, CLH has been found in south Texas so far.
Adult CLH are about 1/8 inch in length, torpedo-shaped, and have a light tan to yellow coloration. The most distinguishing characteristic of the adults are the two black spots located on the top of the head between the eyes. The nymphs look like adults but lack wings. The adults are highly mobile and will fly away when disturbed. The adults can be found in the corn whorl feeding or on the underside of leaves. Nymphs are typically found on the undersides of leaves. It is very important not to falsely identify other leafhopper species as CLH. Most leafhoppers found on corn in Louisiana are a species called black-faced leafhoppers. These leafhoppers look like CLH but are distinguished by having four small spots on the head rather than two distinct spots. (Note: Many leafhopper species have spots on the head. If you suspect CLH, collect specimens and confirm identification with LSU AgCenter Extension Agents or Specialists.)
Figure 1. Left: Corn leafhopper adult. Distinguished by two black spots on the head. Right: Black-faced leafhopper adult. Differentiation from CLH by the four smaller black spots on the head.
Corn is considered the primary host where CLH reproduces in Louisiana, but it has been shown to successfully reproduce on eastern gamagrass in greenhouse studies. However, it is not known if eastern gamagrass plays a role in CLH outbreaks in the field. Adults can feed and survive for weeks on many alternative grass species such as Johnsongrass, sorghum, and millet but they will not reproduce.
Feeding from CLH can cause some damage to corn but the primary threat of economic loss comes from the pathogens the pest transmits. It can transmit bacterial and viral pathogens that form a disease complex known as red stunt. When feeding, infected CLH can transmit all of the pathogens after they are acquired from an infected host. Additionally, an infected CLH remains infected for the duration of its life. Currently, corn is the only known reservoir for red stunt disease in Louisiana. When an uninfected CLH feeds on an infected plant, the pathogen needs to multiply in the insect for a few weeks before the newly infected insect can transmit the pathogens. Infection risk is considered most critical during VE to V8; however, transmission may be possible up to R1. Infected plant can display a wide variety of symptoms including yellowing/reddening of leaves, lower canopy desiccation, severe stunting, thin/barren plants, poor pollination/extensive blank ear tips, and incomplete kernel fill.
Visual scouting is not effective for detecting CLH early. The best sampling method is vacuum-sampling plants with a battery-powered leaf vacuum with a black stocking secured over the funnel. Alternatively, a sweep net can be used but it is less effective. Scouting should be focused on the vegetative stages, but noting the presence and extent of symptomatic plants in a field is a good indicator of the level of infestation experienced in the field. Corn leafhoppers will typically be found in whorls or undersides of leaves. Honeydew and sooty mold can also be indicators of CLH infestations. Typically, CLH will congregate on the margins of fields. Symptomatic plants are often observed dispersed along field margins. The corn most likely to experience damage is late planted corn, particularly if it is planted next to earlier planted corn.
We have only experienced light infestations of CLH in Louisiana and no reported economic loss. Currently, our most reliable management strategies are:
If we see CLH start to develop into a major pest then higher rates of seed treatments will provide some control and we have some options for foliar insecticides that have activity. Again, it is important to be mindful that you have a true CLH infestation and not a similar leafhopper species.
Figure 2. Corn plants displaying signs of red stunt infection surrounded by non-symptomatic plants. These plants were found in Franklin Parish in late June. Symptomatic plants were found along field margins.
Figure 3. Left: Ears collected from non-symptomatic corn plants. Right: Ears collected from corn showing signs of red stunt infection.
Shelly Pate Kerns, LSU AgCenter Corn, Cotton, and Grain Sorghum Specialist
As temperatures dipped into freezing early in the week of March 15th -21st, growers were urged to wait and assess any damage until a minimum of 5-7 days after the freezing temperatures that specifically occurred on March 17th. The following week, I started to get many phone calls and went on several on-farm visits to assess the damage myself. The following is a collection of what I have seen and information that I have anecdotally gathered from industry representatives, corn growers, and crop consultants.
Seed availability has been a huge setback. Prior to planting, seed availability was already in issue for most companies. I have not spoken to one person who is replanting that was able to get more of the hybrids they originally planted. This has many growers nervous that on top of replant costs, they are now working with hybrids they didn’t originally pick, and they are nervous about if those hybrids will meet their yield expectations.
As for the acreage that already has/is going into replant. I have seen several factors that led to replant decisions. Theoretically, if the corn was at any growth stage before the V5 growth stage, the growing point should have been underground and protected. Historically, if we get down to at least 27-degree F, the growing point will still get dinged, and the closer it is to the soil surface, the more susceptible it is to damage. The low dewpoint that was also happening during that time did not help things. Corn that was past the V3 growth stage seemed to fair ok in most areas of the state. However, in those fields, patchy stand where freeze damage occurred did lead to replant decisions in some cases. These plants were also more prone to wind damage that came with the freezing temperatures, and winds ripped leaves of plants with more green material above ground.
To me, the corn fields that more difficult to determine replant in (and the ones that got hit the hardest) were those with “buggy-whipped” (BW) plants. This is where the top of the whorl gets wrapped up and fails to unfurl because the newest leaf essentially turns into a restrictive band. It is common response of young corn plants to freezing temperatures. In some fields, these BW plants were able to get enough energy to finally unfurl (especially some of those plants around the V2-early V3 growth stage that had more root/seed energy reserved to bounce back ok. However, by 8-10 days after the freeze,hard calls needed to be made as we were losing soil moisture, and many farmers were just unsure of the potential of these plants to bounce back. Again, by 8-10 days after planting, there was still green material, but the plants were still unable to unfurl in most cases. When taking stand, the stand would be fine because the plants were green. However, at this point it became crucial to also start unwinding furls by hand to check for rotting, and to dig up plants to look at the growing points. In a lot of cases, 8-10 days after the freeze, the growing points on these plants were starting to turn mushy, and once the cells start to die, there is no coming back from that. Also in these prolonged BW situations, even if the plant could have managed to bounce back, there were often plants in the field that had not taken as much damage and continued to grow. So, even if the BW plants were able to eventually bounce back, they would have been so far behind those other plants that pollination timing and competition between plants of different growth stages would have caused a number of issues. The main point here is that unfortunately, in a lot of replant situations this year, there were a lot of other important factors to consider than just stand itself.
After the freeze, I have heard that a fair estimate would be that 60-70% of what was planted will be going into replant acres (either back into corn or into another crop (estimated 10-15%)). This was a devastating start for many corn growers, with input costs (especially fertilizer) being elevated this year. It will be interesting to see how those acres that will be replanted into another crop will sway previous planting intentions for said crops. Hopefully, the rest of the 2026 corn season will be kinder to us.
Stacia L. Davis Conger, Ph.D. and Michael A. Deliberto, Ph.D., LSU AgCenter Scientists
As planting transitions into in-season management practices, irrigation may be needed if dry conditions continue into summer. Considering rising energy prices, the economic benefit of applying irrigation can only be realized if used strategically. On a per acre basis, irrigation applications using diesel are now over $14 per event, which is almost 20% more than 2016 estimates. Thus, the following options should be considered to improve efficiency.
If purchasing polytubing from Delta Plastics, this is an easy-to-use free tool that can create hole punch guidelines. While useful for any field, it applies the engineering needed to maintain proper pressure along the pipe, irrigate point rows efficiently, set up unique layouts/sets, and estimate the time to water out. The most important parameters include average flow rate from the water source and significant elevation changes along the pipe’s path. You can find this app at www.pipeplanner.com.
Surging water down furrows saves water by 10%-30% depending on soil type. Surge valves automate surging for a single set, but fields can be surged manually by alternating applications across two or more fields. The manual process includes breaking each full irrigation time into 3-4 equal pulses (e.g., a 24-hour irrigation event can be broken into three 8-hour or four 6-hour pulses) or more. After the first pulse on one set, switch to irrigating the first pulse on another set and alternate until completely watering out both fields. Valves automate this process for incorporation into normal irrigation routines.
Surge Irrigation | Mississippi State University Extension Service
https://extensionpubs.unl.edu/publication/g1868/surge-irrigation-management
Sensors provide information about the soil water status in the root zone. Whether using a single Watermark sensor or a tube-style sensor suite, the information obtained from the device can assist in determining when to apply irrigation, including seasonal initiation and termination dates. There needs to be sufficient moisture in the root zone throughout the crop’s reproductive growth stages.
Scheduling Irrigation for Agronomic Crops Using Estimation Methods
Considerations for Scheduling Irrigation in Agronomic Crops
Irrigation Scheduling Using Tension Sensors - Alabama Cooperative Extension System
Manual control of each well has become impractical as farmers take on more acreage. This product will add remote access to existing pumps using cellular service. In addition to on/off features, these products can send alerts, create irrigation history records, and build accountability for operators. Surge irrigation without a butterfly valve may be streamlined; as the technology matures, pump control will link with automatic valves, including surge valves, to streamline irrigation management.
If you have questions or want additional information about any of these technologies or practices, please contact Dr. Stacia Conger at (318) 408-0973 or sdavis@agcenter.lsu.edu.
Craig Gautreaux and Jeff Davis, LSU AgCenter
In this LSU
AgCenter video, LSU AgCenter entomologist Jeff Davis notes that cover crops can offer benefits like nitrogen fixation, erosion control, weed suppression, and habitat for beneficial insects, but they can also harbor pests such as stink bugs, aphids, thrips, spider mites, and whiteflies. If not terminated at least four weeks before planting, these pests may invade new crops. However, beneficial predators like spiders and lady beetles also migrate from cover crops to fields. Effective cover crop management (e.g. timely burndown) is essential to maximize their value and minimize pest risks.
Craig Gautreaux and David Moseley, LSU AgCenter
This LSU AgCenter video covers Louisiana's current soybean planting progress and conditions. It mentions slightly better prices from 2024, persistent high input costs, and more soybean acres expected after a mid-March freeze damaged corn fields.
David Moseley, LSU AgCenter Soybean Specialists
The initial planting for a soybean date of planting by population trial at the Dean Lee Research and Extension Center occurred on March 3, 2026. On March 17, 2026, a freeze event resulted in damage to the unifoliate leaves and apical meristem (the primary growing point) of the main stem. However, by March 23, 2026, most plants exhibited axillary branch development originating from the cotyledon node. Provided these axillary branches continue to develop, it is likely that the affected plants will not experience yield loss as a result of the freeze. It was observed that the plants in the first two rows of the field appeared to not survive the freeze. The first planting progress report from USDA-NASS was for the week ending on March 22, 2026, and only 1% of the Louisiana soybean crop had been planted.
Figure 1. (Top left) Healthy soybean plants on March 16, 2026. (Top right) Damaged unifoliate leaves on March 17, 2026. (Bottom left) Damaged unifoliate leaves and apical meristems on March 19, 2026. (Bottom right) Axillary branches beginning to form on March 23, 2026.
Figure 2. The plants in the first two rows of the field did not show signs of recovery on March 23, 2026.
Figure 3. (Left) The apical dominance was not damage and the main stem continued to grow. (Right) The apical dominance was damaged and two axillary branches grew at the cotyledon node.
Figure 4. Overall, the stand looks good and the plants appear healthy.
| Specialty | Crop Responsibilities | Name | Phone |
| Soybeans | Agronomic | David Moseley | 318-473-6520 |
| Wheat | Agronomic | Boyd Padgett | 318-614-4354 |
| Pathology | Cotton, grain sorghum, soybeans | Boyd Padgett | 318-614-4354 |
| Pathology | Corn, cotton, grain sorghum, soybeans, wheat | Trey Price | 318-235-9805 |
| Entomology | Corn, cotton, grain sorghum, soybeans, wheat | James Villegas |
225-266-3805 |
| Weed science | Corn, cotton, grain sorghum, soybeans | Stephen Ippolito | 318-473-6520 |
| Nematodes | Agronomic | Tristan Watson | 225-578-1464 |
| Irrigation | Corn, cotton, grain sorghum, soybeans | Stacia Davis Conger | 904-891-1103 |
| Ag economics | Cotton, feed grains, soybeans | Kurt Guidry | 225-578-3282 |
| Soil fertility | Corn, cotton, grain sorghum, soybeans | Leandro Vieira | 225-578-2110 |
| Corn, Cotton, and Grain Sorghum | Agronomic |
Shelly Pate Kerns | 318-435-2908 |
| Entomology | Field Crops | Dawson Kerns | 806-474-7220 |
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