This edition covers current crop progress and issues, effect of time of flooding on rice at PD, how to identify Cercospora, and proper fungicide timing.
This edition covers the current weather concerns, hail damage on rice, rice survival under submerged conditions, stretched rice management, estimating lost N from draining submerged rice, and the retirement of Dr. Levy the state soybean extension specialist.
With the abnormally warm winter and spring, cotton planting in Louisiana has gotten off to an early start. In Louisiana, and across most of cotton states, thrips are considered the number one early season insect pest. The species we encounter greater than 85% of the time is tobacco thrips with western flower thrips typically comprising the other 15%.
Thrips control options are limited to seed treatments, in-furrow applications and foliar sprays. Over the past few years, control of tobacco thrips with thiamethoxam (Avicta, Cruiser, etc) has been declining and resistance has been confirmed through bioassays. As a result, we have switched almost exclusively to imidacloprid products (Aeris, Gaucho, Acceleron F1) and no longer recommend thiamethoxam (alone) as a seed treatment in cotton. Aeris treated seed contains imidacloprid + thiodicarb and performs very well in our thrips trials and in the field. The use of imidacloprid alone is another option; however, it may not perform as well as Aeris or imidacloprid + an acephate overtreatment. Overtreatment with acephate is an economical option that has demonstrated increased thrips control when applied on top of imidacloprid. Acephate alone controls thrips but the residual is significantly shorter than currently used products and increases the likelihood of foliar follow up applications.
The use of in-furrow applications of imidacloprid and AgLogic 15G are also options that work well for controlling thrips and other early season insects in cotton. AgLogic 15G is an aldicarb based replacement for Temik that is available in either gypsum or corn cob grit formulations with performance very similar to Temik when used at the appropriate rate.
Finally, foliar rescue treatments are utilized when seed treatments have played out. Foliar treatments should be made when immature thrips are present and/or when large numbers of adults are present and damage is occurring. The presence of immature thrips often signifies that the insecticide seed treatment has lost its efficacy. Avoid spraying solely based on plant injury since the damage has already occurred. Below are some considerations when deciding what foliar insecticide to use.
Positives: Relatively inexpensive, good efficacy at high rates, less likely to flare spider mites and aphids than acephate
Negatives: Ineffective towards western flower thrips, less effective than acephate or bidrin when applied at lower rates
Positives: Relatively inexpensive, effective towards western flower thrips
Negatives: May flare spider mites and aphids if present, may be weaker against tobacco thrips in certain circumstances
Positives: Effective, less likely to flare spider mites and aphids than acephate
Negatives: Less flexibility with applications early season
Positives: Effective, least likely to flare spider mites and aphids
Negatives: More expensive, requires adjuvant
Insecticide choice depends on a number of factors such as cost, impact on secondary pests and spectrum of thrips species present. If a foliar thrips treatment is justified, do not wait for a herbicide application and only spray when necessary to avoid flaring spider mites and aphids.
This is the third installment of the Louisiana Rice Notes newsletter for 2017. This edition covers planting progress and the quick start to the rice season in southwest Louisiana, accumulated DD50 heat units so far, rice seedling development, the importance of Clearfield Stewardship Guidelines, starter N fertilizer guidelines, and planning your 2017 disease management program. This edition can also be found on the LSU AgCenter’r rice website (click here to view).
This slightly longer than normal edition covers planting progress, current weather and soil temperatures, a shift in blackbird pressure this year, effect of treating only half of your seed with AV-1011, economic evaluation of using AV-1011 versus replanting, a change to the FirstShot label, a survey and solicitation for information about pyrethroid use in rice, a welcome to Dr. Blake Wilson who was hired as the AgCenter’s new extension rice and sugarcane entomologist, and how to choose the right insecticidal seed treatment in rice for your individual situation.
This edition covers the low germination issue, how to adjust seeding rates due to the low germination issue, AV-1011, Kaput feral hog bait, burndown plant back restrictions and other useful information.
The Projected 2017 Rice Farm Cash Flow Model (Click Here) and Instructions (Click Here) are now available.
The Projected Rice Farm Cash Flow Model was developed to assist producers in planning for the 2017 crop year. The model is an Excel spreadsheet which allows rice producers to enter projected acreage, yield, market price and production cost data for 2017 to estimate net returns above variable production costs and to easily evaluate the impact of changing percent of base planted on net returns.
LSU AgCenter Extension Agents in rice producing parishes conduct a survey every year to determine the rice varieties which are grown in their respective parishes. The data is then broken down further into rice classes including long grain, medium grain, special purpose, hybrid, and Clearfield rice acres. In addition, information about planting methods, reduced tillage acres, and ratoon rice production is included in the survey. Graphical parish maps and pie graphs are also provided. This information can be found on the LSU AgCenter’s website by clicking the following links: Tabular Data & Parish Maps or a complete summary by clicking the image below.