Brown Marmorated Stink Bug: Under the Radar for Most – (Christian Krupke and John Obermeyer)
With the string of beautiful fall days have come multiple sightings of the brown marmorated stink bug (BMSB) around Tippecanoe County homes and campus buildings. Interestingly, only reported by staff members of Purdue's Entomology Department. In comparison, one (1) BMSB was found in the Lafayette area last year.
We're certain, that BMSB are active in many areas of the state, especially on warm, sunny days crawling around on sunlit sides of homes and businesses. As one colleague noted, they seem partial to screens on sunrooms. They, like the Asian lady beetle, BMSB are attempting to gain inside access for overwintering. As these beautiful fall days dwindle, please take a look. Should you find BMSB, please let us know. They are quite distinctive from other brownish stink bugs with the 2 light colored patches on their antennae (see picture). Even more helpful is if you can take an in-focus, close-up picture to send to us. Please include location (county and nearest city) and approximate numbers of BMSB.
Key identifying characteristics for the BMSB
BMSB next to pencil point
A few weeks ago, Dr. Tracy Leskey, USDA-ARS, presented to our department a seminar about their experiences with BMSB around her Maryland research facility, as well as, neighboring urban and farming areas. For those attending the Indiana CCA Conference on December 21, she will be presenting this and updated information. Don't miss this presentation! The reason states in the Midwest continue to mention this insect is because this it is the real McCoy when it comes to an invasive insect becoming a serious threat to agricultural crops. Not to mention the tremendous nuisance it is to home/shop owners in the fall. The good news is that it will take another four or more years before it becomes "pest" status in the state, the bad news is that it likely will.
VIDEO: Considerations for Bean Leaf Beetle Feeding in Late-Maturing Soybean – (Christian Krupke and John Obermeyer)
Admittedly, the following video would have been more timely a few weeks ago. Unfortunately scheduling conflicts didn't allow that to happen. Still, we believe issues addressed in this video will resonate with many pest managers throughout the winter months and into the 2012 growing season. Especially should commodity prices remain high as they are this fall.
The growing conditions this year presented many stresses to our crops, the exact ones probably never to be repeated. The same could be said for insect pests, specifically the bean leaf beetle. This "perfect storm" of fields with very late-maturing soybean and elevated bean leaf beetle populations presented us with ample opportunities to observe their pod feeding abilities. This statewide situation, not seen for over 20 years, caught many pest managers off-guard. Obviously the high commodity prices caused existing, but older, treatment thresholds to be questioned. Overlooked were some timeless IPM precepts, that understanding the targeted pest.
The following video addresses bean leaf beetle identification, biology, and late-season damage to soybean while keeping the marketable portion of the crop foremost in mind. Shown are simple ways to sample for their presence/abundance, an often forgotten step when eyes are concentrating on damage. Too, some very important control considerations for next year are presented.
Adjuvant Used With Herbicides: Factors to Consider – (Thomas N. Jordan, Bill Johnson, and Glenn Nice)
The terminology for herbicidal additives is confusing. It is often assumed that any material that lowers the surface tension of water in the spray mixture or increases the wettability of the spray solution on plant leaf surfaces is an adequate adjuvant. Since the exact role and function of agricultural adjuvants are not fully understood, the various terms that are used to describe spray adjuvants are often erroneously assumed to be synonymous.
The following discussion is intended to describe the different types of adjuvants that are used with herbicides and explain their role in increasing herbicide efficacy.
Adjuvants are materials that facilitate the activity of herbicides or that facilitate or modify characteristics of herbicide formulations or spray solutions.
Adjuvants are used in herbicidal spray solutions as:
Spray modifier agents and utility modifier adjuvants, are usually found as part of the herbicide formulation, and thus, are added to the herbicide product by the manufacturer. Activator agents are the best known class of adjuvants because they are normally purchased separately by the user and added to the herbicidal solution in the spray tank. However, there may be a need, at times, to add an adjuvant from any of the three classes to a spray solution to achieve a desired result.
Most of the commonly used postemergence herbicides will show increased activity when an activator agent is added to the spray mixture. The manufacturer of the herbicide will specify on the product label the specific type of adjuvant to add, as well as the concentration at which the adjuvant should be added in order to maximize the efficacy of the herbicide.
When an adjuvant is required in a herbicidal spray mixture, keep in mind the purpose for adding the adjuvant, and use the type of adjuvant that meets the required need.
If spray drift onto sensitive areas is a problem, buy a product to help control drift, not one which increases penetration of the herbicide into the plant foliage. If foaming in the spray tank is a problem, a product which will lower foaming activity should be considered.
Other than adding an adjuvant to decrease spray drift risk or prevent excessive foaming of the spray solution, on-farm adjuvants should primarily be used in accordance with the product label instructions to increase wetting and penetration of foliar applied herbicides. Thus, an activator is the most common adjuvant used on-farm.
Confusion frequently occurs concerning the proper selection and use of surfactants with herbicides. It is wrong to assume that any product that lowers the surface tension of water or increases the wettability of a spray solution can be used as a surfactant.
For example, such products as household soaps and detergents can combine with hard water to form precipitate or scum causing the herbicide to want to fall out of solution, whereas agricultural surfactants keep the herbicide in solution.
There are four basic groups of agricultural surfactants:
Waterhemp has been a significant weed issue in both corn and soybean production in the central and western cornbelt for the last 10-20 years. Waterhemp has been present in Indiana field surveys for at least the last 10 years; however, recent control issues with glyphosate is moving this weed up on the radar of concern for Indiana growers.
This publication first will provide an overview of the biological characteristics that make waterhemp difficult to manage in agronomic crops. Second, it will provide management strategies to help growers better manage this weed and slow the selection of glyphosate-resistant biotypes.
Waterhemp is a member of the pigweed (or Amaranth) family, which includes other pigweed species commonly found in Indiana including redroot pigweed, smooth pigweed, and occasionally Palmer amaranth. Distinguishing the different pigweed species from one another is challenging, especially in the seedling stages.
• First true leaves are generally longer than other pigweeds (Figure 1).
• Seedlings are hairless with waxy- or glossy-looking leaves.
• Waterhemp and Palmer amaranth stems are hairless, whereas other pigweeds have hairy stems.
Smooth pigweed seedling
As waterhemp matures, it becomes easier to distinguish from the other pigweeds. Waterhemp can range from 4 inches to 12 feet tall, but generally grows to about 4 or 5 feet in most agronomic settings. Mature plant leaves are elongated and often appear waxy or glossy. Stem and leaf color tend to be shades of green, but within a population, some plants often have distinctly red stems or petioles.
Waterhemp is dioecious, meaning that the male and female flowers are on separate pants. The simplest way to distinguish between male and female plants is to rub the mature flowers between your fingers an look for the shiny, black seeds found only on female plants. Redroot and smooth pigweeds are monoecious (that is, the same plant has both male and female flowers). Redroot and smooth pigweeds have denser, more compact seedheads than waterhemp (Figure 2).
Because waterhemp is dioecious, two plants always mix genes when the plant reproduces. This increases a given population's genetic diversity and increases the potential for spreading herbicide resistance and other traits that favor survival in agronomic systems. Pollen movement can transfer herbicide resistance traits across long distances, allowing resistance to quickly jump fences and beyond. Currently, waterhemp populations resistant to ALS-inhibitors, triazines, diphenylethers (PPO-inhibitors), and glyphosate (roundup) have been identified.
ALS-inhibiting herbicides (Pursuit®, Accent®, and many others) were introduced in the mid-1980s and widely used in corn and soybean. After only a few years of use, ALS-resistant waterhemp biotypes were reported throughout the Midwest. This problem grew to such an extent that these herbicides are considered obsolete for waterhemp control.
Prior to the introduction of Roundup Ready® soybean, the primary alternative to ALS-inhibiting herbicides for postemergence waterhemp control in soybean were PPO-inhibiting herbicides (Reflex®, Ultra Blazer®, Cobra®, and others). At present, PPO-resistant waterhemp populations are limited but have been found in several states. Glyphosate-resistant waterhemp populations have been identified in Indiana, Illinois, and several other states.
Control in Corn
Most preplant/preemergence corn herbicides provide effective control or suppression of waterhemp, especially when mixed with atrazine. A follow-up postemergence treatment may be necessary in dense populations or if rainfall promotes emergence later in the season. Postemergence treatments containing atrazine, 2,4-D, dicamba, Status, Callisto, Laudis, Corvus, Impact, and glyphosate (glyphosate-resistant corn) if the waterhemp population is not resistant to glyphosate are effective. Ignite plus atrazine (Liberty Link corn) will control small waterhemp.
Control in Soybean
For best results, start with a preplant or preemergence herbicide that contains sulfentrazone (Authority), flumioxazin (Valor), metoloachlor (Dual). Preemergence herbicides will greatly reduce the waterhemp population, and provide more flexibility in the postemergence application window. A postemergence treatment will usually be required to control late-emerging plants. Effective postemergence treatments include Ultra Blazer, Cobra, Reflex, Flexstar, and Ignite (Liberty Link soybeans), which should be applied when waterhemp plants are less than 4 inches tall. Glyphosate with Warrant or Outlook (Roundup Ready soybean) can be effective where the waterhemp population is not resistant to glyphosate and provide residual control.
The Post Harvest Update and Recertification Workshop will be held December 5, 2011 at the Beck Agricultural Center, Purdue Agronomy Center for Research and Education, 4540 U.S. 52 W., West Lafayette, IN 47906.
Pre-register and save money $95.00 by Dec. 1 and on-site is $110.00. Registration is limited. The schedule of the day:
8:30 AM Registration, Coffee & Donuts
9 AM - 12 PM Sessions Begin
12 - 12:30 PM Catered Lunch Provided
1 - 4 PM Sessions Contiue
4 PM Complete Certification Forms
CCH's have been applied for. Watch for more detail on our Post Harvest and Grain Quality Website: <http://extension.entm.purdue.edu/grainlab/>.