S.G. Wilson, A.S. Culpepper, and A.C. York University of Georgia and N. C. State University MANAGING LARGE MORNINGGLORY IN ROUNDUP – READY COTTON WITH LAY-BY HERBICIDES

STUDY OBJECTIVE: To Evaluate Lay-By Herbicide Options For Controlling Large Pitted Morningglories And Evaluate Plant Injury

Locations Moultrie * Ocilla *

Materials & Methods RR Variety Sprayed at 4-Leaf Stage w/ Commercial Broadcast Sprayer Plots Sprayed At Lay- By w/ Backpack & 14.8 GPA

Materials & Methods Randomized Complete Block Design Four Replications

Materials & Methods Treatments Evaluated At ~ Two And Four Weeks For Efficacy Treatments Evaluated At ~ One And Two Weeks For Injury

Treatments: RU + Aim RU + MSMA Caparol + MSMA Direx + MSMA Valor + MSMA RU RU + Direx RU + Harvade + COC RU + Staple RU + Valor *RU abbreviated for various brands of Monsanto’s glyphosate products at 1 lb ai/A, Staple 0.6 to 0.8/A oz, Direx pt/A when mixed with RUand 2 pt/A when mixed with MSMA, Harvade 6-8 oz/A, Aim oz/A, MSMA 2 lb ai/A Valor 1 oz/A when mixed with RU and 2 oz/A when mixed with MSMA, Caparol 2 pt/A, and COC 1 pt/A.

Morningglory Response to Lay-By Herbicides TREATMENTS 3-4 ft mg* 15 DAT35 DAT RU50 c55 c RU + Direx35 d55 c RU + Harvade + COC53 c63 bc RU + Staple36 d63 bc RU + Valor80 a74 ab RU + Aim65 b58 c RU + MSMA-- Caporal + MSMA55 bc59 c Direx + MSMA55 bc59 c Valor + MSMA81 a83 a * Values followed by the same letter within a column are not different at P=0.05

No Directed Application

Roundup UltraMax 1.6 pt No Directed Application

Roundup UltraMax 1.6 pt + Valor 1 oz No Directed Application

Valor 2 oz + MSMA 2 lb No Directed Application

Roundup UltraMax 1.6 pt + Harvade 6 oz No Directed Application

Morningglory Re-growth Treatments including Aim looked excellent initially, but MG’s suckered back out by 14 DAT (right)

Morningglory Response to Lay-By Herbicides TREATMENTS 2 ft mg* 16 DAT36 DAT RU 59 e67 f RU + Direx 47 g74 c-f RU + Harvade + COC 78 bcd76 def RU + Staple 95 a86 a-d RU + Valor 92 a91 ab RU + Aim 94 a84 a-e RU + MSMA 80 bc89 abc Caporal + MSMA 68 de81 bc Direx + MSMA 72 cd79 c-e Valor + MSMA 88 ab95 a * Values followed by the same letter within a column are not different at P=0.05

Large Pitted Morningglory Response to Lay-By Herbicides TREATMENTS 9 in mg* 15 DAT39 DAT RU 76 c74 c RU + Direx 97 a92 ab RU + Harvade + COC 91 ab87 abc RU + Staple 87 bc84 bc RU + Valor 96 ab94 a RU + Aim 99 a92 ab RU + MSMA 92 ab Caporal + MSMA 91 ab81 cd Direx + MSMA 97 ab84 bc Valor + MSMA -- * Values followed by the same letter within a column are not different at P=0.05

Cotton Response to Lay-By Herbicides* ‘01 (14” cotton, green) ‘02 (23” cotton, bark) ‘03 (15” cotton, bark) 5 DAT14 DAT5 DAT16 DAT7 DAT16 DAT RU0 d 3 d2 c2 d RU + Direx0 d 6 bc9 a7 b2 d RU + Harvade + COC9 c6 c6 bc4 d10 ab12 a RU + Staple0 d 3 d0 d1 d RU + Valor16 b12 b3 cd3 d12 a2 d RU + Aim25 a18 a15 a5 cd12 a3 cd RU + MSMA--3 cd4 d10 ab8 b Caporal + MSMA0 d2 d1 cd6 abc9 ab3 cd Direx + MSMA3 d 9 b8 ab8 b6 bc Valor + MSMA18 b13 ab8 b4 d-- * Values followed by the same letter within a column are not different at P=0.05

Non-treated Control Soil Uptake of Harvade

Herbicide Injury Cotton was extremely green (no woody material) at time of application At 5 DAT, injury ranged from 16-25% for Aim or Valor Mixtures

Summary On 3-4’Mg, RU + Valor or Valor + MSMA were the most effective treatments On 2’ MG, RU + Staple, Valor, or Aim as well as Valor + MSMA were the most effective treatments On 9” Mg, the most effective treatments were Direx, Harvade, Valor, Aim or MSMA when mixed with RU

Summary Tank mixes including Aim and Valor were more injurious Injury was worse on green cotton Harvade injury appeared as leaf chlorosis Injury was short-lived

Summary No differences in yield were noted Early season weed competition was similar across the trial

QUESTIONS?

THE END