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Early Season Insect Pressure

ARKANSAS

Bill Robertson AR

Bill Robertson e-mail

The first 40 days in the life of a cotton plant sets the foundation for yield and fiber quality potential for the season. This includes the period from planting to squaring. Cool temperatures or competition from pests can delay the onset of squaring. In our April-planted cotton, first pinhead square generally occurs 40 to 45 days after planting, compared to mid-May planted cotton, which generally takes about 35 days. This is primarily a function of the cooler temperatures we generally receive the end of April and the first part of May.
Pest management issues have generally been the greatest concerns for our current crop. However, as we move into the next few weeks, other factors including fertility and soil moisture stress become more critical. In dry years, consideration for irrigating pre-squaring cotton may arise. We generally do not irrigate cotton during this timeframe in the Mid-South. Research demonstrates the importance of avoiding stress once squaring begins.

Irrigation water management is our next big challenge. There are many programs, tools and practices available that producers can use to help improve irrigation water-use efficiency. Everyone who uses poly tubing should be using computerized hole selection. We want to go into squaring with a plant developing a new node every 2.5 to 3 days and have square retention greater than 80 percent. This will put us on track to having 9 to 10 nodes above white flower at first flower. Contact your local county Extension agent for more information.

ARIZONA

Randy Norton AZ

Randy Norton e-mail

Early season fruit set has begun with squares and some early flowers being seen across the state. Protecting this early season fruit set is critical to achieving optimum yields while enhancing a timely termination of the crop in the fall. Loss of early fruit set, including young developing squares, may result in excess vegetative growth, delayed maturity and decreased yields. Abortion of young fruiting forms, such as small squares and young flowers, may occur as a result of several factors including environmental stresses such as hot, dry winds or lack of adequate soil moisture, and early season insect pressure.

Last month I discussed proper irrigation and crop water management. This month we want to focus on protecting the early season fruit set from damaging insect pests. Early season insect pests, such as thrips and flea beetles, can have a significant impact on the young developing cotton plant. Recent years have seen record low insect populations across the state, and we have greatly benefited from the ability to manage our cotton crop with minimal insect control
measures.

However, it is critical to monitor the crop for the presence of insect pest populations to ensure that they do not rise to damaging levels. Scouting techniques and control measures have been developed for major pests affecting Arizona cotton by Dr. Peter Ellsworth and his team and can be found on the University of Arizona’s Crop Information Site. For more information on insect detection and control, as well as other cotton production topics, go to: http://cals.arizona.edu/crops.

FLORIDA

David Wright FL

David Wright e-mail

Most cotton is planted with a wait-and-see year for insect pests. Following a mild winter, we expect higher plant bug populations as well as other pests. We had little freezing weather to lower overwintering insects numbers. It’s always a challenge to determine what issues we might face, but with careful scouting, cotton can be managed successfully.

Our average number of insecticide applications is three sprays. Most of those go out during the first three to five weeks of bloom – July and August – to ensure boll set. These are the prime months for bloom and boll set. It is very important in a year with low prices that key production practices are used.

Other things to consider are nitrogen timing with small applications made at planting, followed by an application at squaring. If more applications are needed on sandy sites, all of the nitrogen should be applied before the third week of bloom. We have had no response to nitrogen after that period.

LOUISIANA

Dan Fromme LA

Dan Fromme e-mail

As of May 11, cotton planting across the state is now approximately 40 to 50 percent completed with a significant portion of the acres going in the ground during the last week of April and the first 10 days of May. Overall, temperatures have been excellent, and cotton has been emerging in five to six days. Once planting has been completed and cotton has emerged, producers will make side-dress nitrogen applications.

Thrips populations are currently being monitored in cotton that has not reached the five true-leaf stage. LSU AgCenter entomologists recommend treating when immature thrips first appear on seedling cotton. Once cotton has reached the five true-leaf stage and growing conditions are good, thrips control is no longer needed.

Fleahopper and tarnished plant bug numbers are being monitored in cotton that has started squaring. Scout for fleahoppers during the first three weeks of squaring. Detection can be difficult due to the flighty nature of these insects. Our entomologists recommend treating when 10 to 25 of these insects per 100 plants are found. These treatment levels may be adjusted to maintain between 70 and 85 percent first position square retention.

For tarnished plant bug control, pre-bloom threshold levels are 10 to 25 plant bugs per 100 sweeps. The Louisiana threshold for the bloom-to-harvest period is two to three tarnished plant bugs per 5 feet of black drop cloth, 10 plant bugs per 100 sweeps or 10 percent dirty squares.

Occasionally, clouded plant bugs can be found in Louisiana cotton. Pre-bloom and bloom threshold levels are the same as those for tarnished plant bugs; however, each clouded plant bug should be counted as an equivalent to 1.5 tarnished plant bugs when determining a treatment decision.

MISSISSIPPI

Darrin Dodds MS

Darrin Dodds e-mail

Many folks in Mississippi will likely be glad to see June arrive, given the difficulty of this planting season. Rain showers and cool temperatures persisted into early May, which slowed fieldwork across the state. A planting window finally arrived as we headed into the first weekend in May, and many pushed as hard as possible to get this crop in the ground. For those who managed to get cotton seed in the ground during late April, some re-plants have been necessary due to seedling disease and herbicide injury.

Given prices of all commodities, it will be vital to spend money where needed and save money when you can. Do not let low commodity prices restrict insect and weed management, as each of these practices can have a direct impact on yields. As one farmer has told me repeatedly, “Don’t let a nickel stop a dollar.” However, proceed with caution when considering products that are not proven to provide yield or other necessary benefits. When commodity prices are good, we can afford to experiment to some degree with various products to determine potential yield benefits. However, when prices are low as they currently are, investing wisely will go a long way towards improving your bottom line.

MISSOURI

Mike Milam MO

Mike Milam e-mail

There is an old adage that says, “Be careful what you wish for because you just might get it.” That is certainly true this year related to our planting season. According to the May 9 Missouri Crop Progress and Condition Report, cotton is at 90 percent planted. Last week, we were at 51 percent, which was the amount of cotton planted at this time last year. The five-year average is 29 percent. This gives us some flexibility. If re-planting needs to be done, it can be earlier than the typical re-plant. So we have a lot to be thankful for.

Earlier planted cotton could also mean better conditions at harvest since the crop should mature sooner. I have been concerned about being able to get the cotton out in a timely fashion the past few years since a large amount of cotton was planted well past the optimum planting date.
Although the cotton was harvested later than desired, many factors contributed to not hurting the yield. In fact, in 2014, Missouri producers set a yield record of 1,117 pounds per acre. Last year, we had 1,111 pounds per acre produced. If we have good growing conditions this summer, we could even exceed that.

Now that we have eliminated the boll weevil as a key pest and insect resistance traits take care of worms, tarnished plant bugs are by far our most important pest. Scouting and applying pesticides in a timely fashion, plus rotating chemistries, will help reduce resistance in this pest.

OKLAHOMA

Randy Boman OK

Randy Boman e-mail

As of this writing on May 11, a quick glance at the Oklahoma Mesonet previous 30-day rainfall accumulation graphic shows that some cotton-producing counties have been coming up fairly short compared to others. Basically everything west of a line from Hollis to Elk City has received less than 2 to 3 inches, while areas east of that line have been blessed with about 6 inches or greater. For this time of year, that is really good news.

We are now entering our historical, prime cotton-planting window for irrigated acreage. Soil temperatures have been good over the past week or so, and some producers have begun planting. Areas where rainfall was not as enticing are still waiting for a better moisture situation in the upper profile. We hope we will get off to a great start.

With the good to excellent spring rainfall that we have encountered in many counties, plenty of alternate hosts are growing across the landscape that can harbor cotton insect pests. Producers need to keep an eye on thrips populations and be ready to make topical applications when necessary. Cotton fleahoppers may also be more problematic this year.

As we move forward with planting the 2016 crop, there is a bit of unfinished business for the 2015 crop. I finally had an opportunity to inspect National Agricultural Statistics Service yields and the Abilene U.S. Department of Agriculture-Agricultural Marketing Service final fiber quality summary for the state. It appears that the 2015 crop was one of record yield, 866 pounds per acre for all practices (dryland and irrigated combined). This breaks the previous record of 817 pounds set in 2007.

Several fiber property averages for the crop also set records for the state. HVI length tied a previous record of 36-32nds inch; uniformity set a record at 81.3 percent; and strength was the highest ever at 31.3 g/tex. All of this indicates that producers are paying attention to new genetics – and when we have good rainfall support from Mother Nature, we can produce excellent yields of high-quality fiber.

NORTH CAROLINA

Guy Collins e-mail

Guy Collins
e-mail

The beginning of the 2016 planting window in North Carolina was marked by short periods of suitable planting weather along with intermittent wet or cool spells. Rains during the last week of April and first week of May slowed planting progress in many areas. Very little cotton was planted during late April and the first week of May. Fields that were planted during that time were slow to emerge due to cool temperatures and intense rains.
As I write this on May 5, afternoon temperatures in the middle of the state are in the mid-50s, and nearly all cotton-growing regions in the state have received significant rains. However, the weather forecast for the second week of May looks decent, so we hope fields will dry out enough to allow planting to proceed without major delay.

For most cotton, June will be the time for several critical management decisions. Early season plant growth regulator management may be necessary in some fields but only after careful scouting to determine such need. Additionally, first square will mark the beginning of timely irrigation needs if dry, hot conditions prevail. Lastly, growers and scouts should monitor closely for plant bugs during June. Frequent scouting, quick action and timely sprays (if thresholds are reached), and rotation of chemistries are critical to combating this insect pest.

TENNESSEE

Tyson Raper TN

Tyson Raper e-mail

As I write this on the May 11, Tennessee has already had two decent windows in which to plant cotton (one of which may close tomorrow with another half-inch of forecasted rain). Rain chances for the next week are relatively high, but with a little luck, Tennessee will have all of its cotton in the ground within the next two weeks. From what I can gather, between half to three-quarters of our cotton acreage has already been planted, with only a few areas needing to be replanted. That puts us ahead of 2015 by roughly a week.

Still, managing for earliness extends far beyond planting. Several stresses must be prevented or addressed in order to capitalize on our timely planting. Research by Dr. Scott Stewart in Tennessee has indicated positive impacts from foliar applications of insecticides targeting thrips at the one true-leaf stage. Preventing thrips from damaging the young seedling will allow it to quickly progress out of the susceptible growth stages. This is particularly important for seedlings struggling through injury from a pre-emergence herbicide, as the two stresses commonly interact to severely delay maturity.
For additional information on these and other management activities that emphasize earliness, visit our website at UTcrops.com or blog at news.utcrops.com.

TEXAS

Galon Morgan TX

Gaylon Morgan e-mail

Cotton growth stages varied widely from the Rio Grande Valley (6-18 nodes) to the Blacklands of Texas within each region. Replanting was common from the Coastal Bend northward due to some heavy rainfall events, while the Northern Blacklands still has significant acres to be planted. With the rainfall, weed pressure has been high and a challenge for producers to get sprayed in a timely manner, but overall weed control has been good.

Glyphosate-resistant pigweeds continue to pop up in new places, but producers are generally staying on top of the situation. Cotton aphids have been a problem in the RGV, where many producers have already made multiple insecticide applications. Fewer reports of high thrips numbers have occurred thus far; however, reports of early applications for fleahoppers have come from the mid-coast region.

The Northern Rolling Plains began planting irrigated fields during the second week of May. In the Southern Rolling Plains, planting will likely begin mid-May. Dryland cotton planting will immediately follow the irrigated cotton plantings, assuming sufficient surface moisture is available.
There has been a lot of discussion on reducing seeding rates to cut down on input costs, but I think most people will stay within a reasonable seeding rate. Soil profile moisture is generally good, but many locations in the Rolling Plains are still in need of planting moisture to establish a good stand.

TEXAS

Seth Byrd TX

Seth Byrd e-mail

As of May 10, cotton planting was underway full force in the Texas High Plains, particularly on irrigated ground while a rain in mid-May would likely spur planting on dryland acres. As of early June, scouting for insect pests will become a primary concern. Although issues due to insects are hit and miss and vary year to year across this area, several pest species can reach damaging levels, including spider mites, cotton fleahopper and western tarnished plant bug, among others.

Different insect pests can affect cotton at various points during the season. Scouting accordingly can help make timely decisions regarding control methods and prevent a severe problem. Also, understanding how control methods targeting one species may influence or affect other insect pests and beneficials is key to avoid creating additional issues. Information on insect identification, scouting procedures, threshold levels and control options can be found at cottonbugs.tamu.edu.
Weeds are another key pest to be on the lookout for during the early part of the season. Controlling weeds that may have escaped pre-emergence herbicides or even the first post application is crucial to avoid competition with the crop for water and nutrients. Selecting proper herbicides for the weed species present and rotating modes of action from those previously applied can aid in achieving clean fields, managing resistance and avoiding the dreaded hand weeding later in the year.

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