Manage Bloom Period Carefully

ARKANSAS

Even with the difficult start we have experienced with this crop, we should be on track to find flowers by July 4. The status of our cotton plants at first flower reveals much about the past and gives us an indication of what we must do down the road to end up where we want to be.

Ideally, we will find nine to 10 first position fruit above the uppermost first position white flower at first flower. This verifies that we have the foundation to set and mature high yield and fiber quality potentials. Our goal is to maintain 80 percent retention going into first flower. Problems that can directly impact yield and profit are extremely high fruit retention rates as well as low retention rates. Going into flowering with extremely high retention can set you up for failure if any problems are encountered as the margin for error is small. Compensation for lost fruit late in the season is often very costly.

Maintaining a balance between vegetative and reproductive growth will help to optimize earliness and preserve yield and fiber quality potential. Irrigation initiation and timing play dominant roles in this balance. Utilizing sensors and scheduling tools along with programs such as Pipe Planner will help improve irrigation water-use efficiency and profitability. An effective fruiting window of three weeks between first flower and cutout (NAWF=5) will provide the yield and earliness cotton producers in Arkansas desire.

FLORIDA

Cotton and peanut are mainstays of agronomic crops grown in Florida due to their drought tolerance on sandy soils compared to corn and soybeans. Both cotton and peanut bloom over an eight-week period or longer with high demand for water during the bloom period.

Even though Florida has a total of about 2 million irrigated crop acres, most of the irrigation is for high-value horticultural crops. About 20 percent of the cotton acreage is irrigated. However, non-irrigated cotton often does as well as the irrigated due to frequent rainfall in July and August when the crop has peak demand.
Many of our producers who irrigate are using moisture sensors to maintain adequate moisture in the soil profile without leaching nitrogen and potassium below the root zone. Florida producers who grow cotton after peanut and grow winter grazing prior to cotton planting have found that nutrients are recycled through livestock.

Also, cotton rooting is deeper with enhanced rooting (almost twice the root mass) resulting in as much as 50 percent less irrigation and nitrogen fertilizer use with yields of 2- to 4-bale cotton. More of our growers are working to integrate livestock into the cropping system to reduce water and nutrient use while making higher cotton yields.

LOUISIANA

The Louisiana cotton crop looks very promising. DD60s accumulated for the past 60 days are above average compared to the historical average for this time period. Thrips pressure was extremely heavy this year. Soil moisture is very good in most parts of the state.

As of June 10, most of the cotton fields were squaring. Plant growth regulator applications will be going out to manage plant height and excess vegetative growth. Earlier planted fields in central Louisiana will be approaching first bloom in about 10 to 14 days. Since squaring began, insect pressure from aphids, fleahoppers and plant bugs has been low throughout most parts of the state. Square set is looking very good with fields having 80 to 85 percent or higher square retention.

As cotton fields in Louisiana reach early bloom, an effective method for farmers to determine vigor, or the amount of horsepower the cotton plant has, is to count the number of nodes above white flower (NAWF). NAWF is measured by counting the number of nodes above the lowest first position white flower on the cotton plant. The last node to be counted at the top of the plant will be the uppermost node that has an unfurled main stem leaf larger than a quarter (greater than 1 inch diameter).

Factors that influence NAWF at early bloom are maturity differences in varieties, soil moisture conditions, insect pressure and disease. At early bloom, NAWF can be at 5 or 6 under drought-stressed conditions to 10 or more under optimum growing conditions. Fewer NAWF at early bloom indicates an early cutout is eminent and there is potential for low lint yields. Higher NAWF counts of 9 or 10 indicate that the plant has ample horsepower and the potential for an excellent crop.

MISSISSIPPI

I am always amazed at how we tend to go from one extreme to another in terms of water. Most of Mississippi was wet and cold for the majority of the spring; however, once cotton planters began to roll, rainfall was non-existent for up to five weeks in some areas. I have always heard that at any given time we are only seven days away from a drought. This is true, particularly during July and August.

As long as irrigation has been a part of cotton production in Mississippi, we have watered cotton based on personal experience and whatever data could be found. Although cotton is generally considered one of the more drought-tolerant row crops, rainfall and/or irrigation can help stabilize and increase yields.
More scientific methods for irrigation are available every year, which include computerized hole-selection programs for poly tubing, soil moisture sensors, and surge valves, among others.

In order to make the most of our limited water resources, I encourage you to take a look at any or all of the tools available to help increase irrigation efficiency. Given the continual increase in human population and the fact that no more land is being made, we will be forced to produce more food and fiber on the land we have. Making the most out of limited water resources will be of paramount importance to crop production in the coming years.

MISSOURI

The Missouri cotton crop was planted in a timely fashion this season. However, some fields had to be replanted due to rainfall. I have seen many fields that did not drain well after several storms. Other fields had excellent drainage, and the water got off the field very rapidly.

Although we had timely planting, rainfall has put a stop to most field operations. We have had rainfall on nine of the past 14 days. We have had excellent temperatures this past month. The cooler night temperatures have given way to the higher range that we normally expect at this time of the year.

In looking at the May 31 Crop Progress and Condition Report, the condition of the cotton crop is 3 percent very poor, 8 percent poor, 40 percent fair, 46 percent good, and 3 percent excellent. In looking at the crop’s condition from the previous week, there was an 11 percent drop in the good category to the fair category.

The Drought Monitor shows that we have excellent moisture. The 3-month forecasts show above-normal temperatures with equal chances of below-, average and above-average rainfall. One of my concerns is that with the available moisture near the surface, the roots have no incentive to move deeper into the soil profile. Therefore, producers who don’t have supplemental irrigation are at risk later in the summer.

TENNESSEE

Given the water and irrigation theme for this issue of Cotton Farming, I thought it might be appropriate to briefly cover some best management practices for irrigated acres in Tennessee. We definitely want to start the flowering period with adequate soil moisture and remain at that state through boll fill.

Although some research has indicated pre-flower irrigations can increase yields under periods of severe stress, irrigations are rarely justified pre-square and uncommon during pre-flower. Proper termination timing varies by production system. However, by the time bolls crack, Tennessee cotton farmers should consider shutting off the pump in most irrigated fields.

As anyone who has attempted to irrigate a crop knows, the hardest part is figuring out how much you need and how much you have. The good news is advancements in technology are moving us closer to having a complete picture of available water and plant demand. In the meantime, I encourage you to check out an atmometer. This instrument measures the rate at which water evaporates and gives insight to atmospheric demand across a large area. When coupled with a solid number for typical crop water use by growth stage, it can give you a good feel for how much water should be applied and when.

TEXAS

Across the state, excessive rain has been a blessing and a curse for the cotton crop. The Rio Grande Valley has had timely rainfall, and both dryland and irrigated cotton are progressing nicely and look good. The combination of prolonged saturated soils and high plant nutrient demand for early bloom cotton has led to immobile, nutrient-deficient (yellow) cotton. Sunshine and dry weather will cure the deficiency symptoms as root uptake of nutrients increases. Foliar fertilizers will not likely be economical in this scenario.
The Upper Gulf Coast and Southern Blacklands cotton has been saturated for months but continues to hang on and look decent, except for flooded-out areas. The Northern Blacklands never reached its acreage potential due to the inability to plant in wet conditions.

When dry, sunny weather returns across South and East Texas, producers need to be prepared for plant growth regulator applications. The timing and large plant sizes will require higher rates than usual, especially for the more vigorous varieties.
Planting in the Northern and Southern Rolling Plains has progressed slowly due to wet conditions in late May. However, with dry weather predicted for the first half of June, the odds are good for completing cotton planting before the June 20 final planting date.

Weed management has been a challenge for timely herbicide applications due to poor access to wet fields, additional weed flushes and fast-growing weeds. Although the pre-emergence herbicides broke down more quickly than usual, they still provided good early season weed control. Cotton fields that did not receive a pre-emergence herbicide, are fairly obvious and will present a challenge for the remainder of the season.

Rainfall in 2015 and 2016 has helped flush some of the salts from our irrigated land and helped replenish a few of the shallow aquifers. Although we have been fortunate not to need irrigation yet, it is Texas, and we will be short of moisture before we know it.

TEXAS

The middle of May saw a lot of cotton go in the ground in the Northern High Plains. Most southern areas waited until moisture conditions improved and began planting heavily at the end of May and into early June. As of June 8, cotton planting was complete on approximately 75 to 80 percent of the acres in the region. Although it would be ideal to plant earlier, the vast majority of the High Plains planted into good soil moisture, and temperatures have generally been suitable for rapid growth and crop development. So we were set up with a good start to the season although it was a week or two later than planned.

With adequate to plentiful moisture available throughout most of the region, the crop may make it to bloom with few, if any, irrigation applications needed. Cotton typically requires little water to make it through the vegetative growth stages; however, avoiding stress is still critical. Supplemental irrigation may be necessary if long-term drought conditions persist. Cool temperatures delayed the development of early planted cotton, likely resulting in a fairly similar first bloom date across most of the region despite two to three weeks difference in planting date.

Entering bloom in mid- to late July will leave plenty of time to produce a high-yielding crop if the weather cooperates later in the summer and an early frost is avoided. Since the crop is getting off to an overall late start, square and boll retention will be key to success. Balancing water requirements through irrigation and growth regulation through timely plant growth regulator applications will aid in achieving a high-yielding and manageable crop in what could be a shortened season.

VIRGINIA

As we move into July, cotton in Virginia is two to three weeks behind where it is normally. Unseasonably cool temperatures and excess rainfall from May 1 to May 20 resulted in only 79 percent of the expected crop planted by June 5. With that in mind, Virginia cotton acres could be down as much as 21 percent from 2015. From here on out, cotton producers in Virginia are going to need nearly perfect conditions to average 1,000-plus pounds of lint per acre.

Since Virginia has less than 5 percent irrigated acres, Mother Nature is considered the sole provider of water in the state. Given late planting dates, producers need to be mindful of plant growth regulator applications and timely insect control to ensure no delay in crop maturity this fall. Nitrogen management also will be an important component in managing crop maturity. High nitrogen rates could delay maturity, especially if dry conditions prevail in July and August followed by rain in September. This may be a good year to split side-dress nitrogen applications and evaluate nitrogen status by tissue and petiole testing during the first week of bloom. Our data indicated over the past three years that petiole nitrate levels 4,600 ppm NO3-N (nitrate as nitrogen) or higher during the first week of bloom were enough to achieve optimum yields. In-season monitoring of N will be the best way to ensure nitrogen is not over-applied in a shortened growing season, which would delay crop maturity.

We can still achieve yields greater than 1,000 pounds, but we have to stay on top of plant growth regulators, insects and soil fertility management to ensure a timely harvest in 2016.