Late Planted COTTON Tips from UGA Cotton Agronomists – Jared Whitaker & Mark Freeman
Many of our cotton acres have been planted in the month of June. Although yields tend to decrease as we move past the 10th of June there is still potential for profitable yields.
- Consider increasing seeding rates – Shoot for a final plant stand of 2 plants/foot
- Decrease any stress – Irrigate to promote stand establishment, enhance fruit retention and eliminate stress during dry periods
- PGR’s – Mepiquat products should be applied to prevent excessive vegetative growth and decrease boll rot, and retain fruit on the lower position bolls which promotes crop earliness.
- Varieties – Varieties should be chosen on overall yield potential NOT maturity characteristics. (Most available varieties only differ by a few days to a week.)
- Fertility – Decrease N rates by 25%-30% to limit excessive vegetative growth. This should be done by taking some off pre-plant and sidedress. (Consider 20 lb N at plant and 55 lb N at sidedress. If you put out 30 at plant before rains in May and did not plant until June you will still have 10-20 lb N available so just do the N sidedress early.
Other things to keep in mind from specialists: Phillip Roberts, Wes Porter and Glen Harris
Scout closely and use thresholds
- Thrips are usually low on late planted cotton as long as plants are growing rapidly
- Aphids will infest younger cotton, stress could delay development
- Tarnished Plant Bug affects square retention use sweep nets and drop cloths to monitor. Shoot for 80% square retention.
- Corn Earworm watch for in mid-July, though the newer 3 Bt gene varieties are less susceptible no cotton is immune.
- Stink Bug infestations will be higher in late planted cotton. Scout and treat as needed, remember thresholds are lower during the 3rd-5th week of bloom.
Planter Settings – watch down pressure and soil contact when planting into less than ideal soils. Make sure the wheel is not pressing down to hard and making trenches or compacting. At the same time in rough fields see that seeds are getting covered with soil.
Nutrients Leached by Rains – The most mobile of the nutrients are nitrogen, sulfur and boron. Each scenario is different but consider replacing lost nutrients at sidedressing time between first square and first bloom. Keep in mind that saturated soils early on and through the season may mean that your nutrients have not leached but compromised root systems cannot pull them up.
PEANUT Update: Compiled from specialists- Mark Abney, Scott Monfort and Bob Kemerait
- Young peanuts showing signs of yellowing and stunting is likely the result of saturated soils. The nodules on the peanut roots need oxygen to do their job of fixing nitrogen. Prolonged wet periods can cause nodules to become inactive. Check by pinching them in half to see if they are pink, red or purple inside. If not they may not be fixing nitrogen. Reduced nodulation could call for a rescue N application in some cases.
- June planted acres are at increased risk for late season caterpillar infestations. Scout on time and treat according to thresholds. So far there have been reports of lesser cornstalk borers and southern corn rootworm from across the state. Thrips populations have be very variable this year. We are beginning to see tomato spotted wilt virus associated with their feeding.
- Aspergillus crown rot has been a problem in wet fields. Conditions are perfect for white mold and leaf spot. We have new fungicide Peanut Rx for 2018 call me or come by for a copy. I can also email out fungicide spray sheets from several different companies if you need it.
CORN Update: Compiled from specialist- Bob Kemerait
- To date there has been no southern rust found in Georgia. Conditions have been favorable for it. Preventative sprays should be applied at the pre or tassel stage for rust with a strobilurin fungicide.
- There have been reports of southern and northern corn leaf blight. Sprays for this are best when done at the V6-V10 stage for late planted corn. Use a combination product – strobilurin + triazole or strobilurin + SDHI for this disease.
- Strobilurin fungicides or combination products tend to have a longer protective window than just triazoles alone. Making a fungicide application at this point in the season is a grower preference if there are no diseases present in the field.
- Corn smut has been abundant this year (the blue moldy looking stuff that takes over the ear). The wet weather has contributed to this. Unless the variety is extremely susceptible there is little yield loss.
Late Planted SOYBEAN Tips from UGA Specialist – Mark Freeman
In Georgia the optimum planting window for soybeans is May 10th thru June 10th, however, the planting window can be extended through June 30th if well adapted late maturing varieties are used. Although the planting window can be shifted later, one should still expect yield potential to decline about ½ to ¾ bushel/A for every day planting is delayed after June 10.
- Select the Correct Maturity Group – Group V and VI beans still respond with decreased yield at later planting dates. Group VII has consistent yield over all late planting dates. If early varieties are planted to late they will flower before they grow enough to produce optimal yield.
- Increase Seeding Rates – consider moving from 6 seed/ft to 9 seed/ft (90,000 per acre to 130,000)
- Decrease row Spacing – more narrow row plantings increase yield by 0.7% per inch and can help with weed control
- Watch Pests – late planted beans will see higher numbers of stink bugs and foliage feeding caterpillars. Identify the pest and treat accordingly. Use Dimilin at the R2-R3 stage as a preventative for velvetbean caterpillar and green cloverworm.
General Comment on All ROW Crops
Wet soils have altered the way many people apply herbicides. If you have an escaped weed or delay in your spray schedule that you need input on, please give me a call. We will help you find the best option for your situation.