AUBURN, Ala.—Recent rains have improved soil moisture conditions, but more than 30 percent of the state’s topsoil is rated short or very short on moisture. That is about double the 5 year average. Producers have struggled with when to plant because of the persistent droughty conditions that have lingered since late 2016.
Most cotton producers aim to have cotton in the ground between April 20 and May 10. While there is still time, producers are hopeful for a good, soaking rain that will enable them to begin planting full steam ahead.
Alabama Cooperative Extension System professionals developed guidelines for spring planting in warm, dry conditions. Additional information can be found in the free, downloadable resource—the Climate and Crops iBook.
There will likely be a high risk for delayed planting due to warm, dry spring conditions.
- Prepare seedbed early to be ready for planting when sufficient moisture may become available. Adequate moisture at the 1/2 – to 1-inch soil depth where cottonseed is planted is critical for germination.
- Under these warmer and drier conditions, consider having access to an extra set of planters ready to capitalize on any rainfall event.
- With onboard GPS-guided tractors and implements, growers can plant night and day to capture the benefits of a timely rainfall event.
Warmer and drier winters increase the risk for overwintering grasshoppers, leading to higher numbers of these insects in the spring. In recent years, this has become a special challenge in reduced tillage systems.
Likewise, warmer and drier winters promote the overwintering of bollworm and tobacco budworm pupae.
Warmer and drier spring conditions likely will result in earlier moving of thrips off host plants onto early planted cotton. Nuisance pests, such as false chinch bugs and white munching burrowing bugs, are likely found in these weather conditions.
Warmer and drier spring conditions also have a major effect on the plant bugs moving from wild plants onto cotton. The bugs move quickly onto cotton during the early fruiting season as the wild plants are drying down. This behavior is sharply opposed to wetter springs when the wild plants remain greener longer and the plant bugs slowly migrate into cotton over longer periods.
The potential for stinkbug damage is correlated with moisture throughout the bloom period with dry conditions resulting in lower damage. Dry weather also negatively influences early season host plants, resulting in fewer stinkbugs and lower damage.
The increased incidence of miscellaneous pests, such as chinch bugs, is also likely under drier and warmer weather.
Insect Management Strategies
- Growers who anticipate warmer and drier conditions at planting should consider using an insecticide during cover crop burndown to suppress grasshopper populations.
- Because movement of plant bugs from wild plant hosts to cotton typically occurs under warmer and drier spring conditions, growers should anticipate making more insecticide applications to control this pest.
- To manage thrips, growers typically should use a seed treatment or in-furrow application of a systemic insecticide. Dry soil can also limit insecticide uptake by seedlings, thereby increasing the risk of significant thrips damage to the cotyledons and first true leaves. Supplemental foliar insecticide applications may be needed if environmental conditions are not conducive to uptake of at-planting systemic insecticides or if heavy thrips infestations occur. Planting cotton in late May and early June instead of April and mid-May may greatly reduce thrips pressure.
- Following integrated pest management (IPM) strategies, growers should scout for other insect species and react accordingly throughout the crop season.
Pre-emergence herbicides are applied to the soil before weed emergence. Warm conditions can affect the herbicide’s half-life and shorten the weed control period. Dry conditions may prevent movement of the herbicide into the seed germination zone (called activation). This may also result in heavy weed pressure.
Warm, wet early season conditions encourage rapid crop growth. These conditions may also result in early season weed growth.
Weed Management Strategies
- To prevent losses due to weed pressure and to avoid herbicide-resistance development, weed management strategies should include residual and post-emergence options before planting, in early season, and during the lay-by period.
Climate and Crops iBook
Climate and Crops is intended to be a comprehensive resource not only for farmers, crop consultants and Cooperative Extension professionals but also for school teachers who want to introduce their students to how farming practices are increasingly being adapted to new findings about climate variability.
Each chapter includes basic considerations associated with crop production. Additionally, each chapter covers potential climatic conditions that may occur during the growing season and how these affect each of the principal crops in terms of planting, crop growth and development, insect, weed and disease pressure and harvesting. Farmers are given a list of risks, along with the most effective management strategies for each of these climate scenarios.
Learn more about Climate and Crops at http://www.aces.edu/climateandcrops.