A. W. Ezell, J. L. Yeiser, and L. R. Nelson

1. HERBACEOUS WEEED CONTROL IN FIRST – YEAR LOBLOLLY PINE PLANTATIONS USING OUST XP, OUST EXTRA, OUSTAR, MATRIX, AND STEADFAST A. W. Ezell, J. L. Yeiser, and L. R. Nelson

2. Acknowledgements • Dupont Chemical Company • Plum Creek Timber Company • Boise-Cascade

3. Background • Herbaceous weed control is an essential component of loblolly pine plantation establishment • Evaluation on new or currently labeled products may produce new options for land managers

4. MATERIALS AND METHODS • STUDY SITES • MISSISSIPPI • Plum Creek Timber Co. land • Previous Cover = mixed pine-hardwood natural stand • Harvested – 2002 • Chemical site preparation – 2003 • Subsoiled – 2003 • Hand planted with 1-0 loblolly – January 2004 • Soils = sandy clay loam, pH = 5.3

6. Texas • Boise-Cascade land • Harvested – Oct, 2002 • Shear – July, 2003 • Burn – August, 2003 • Machine planted with 1-0 loblolly – January, 2004 • Soil = Eastwood fine sandy loam

8. South Carolina • Nonindustrial private land • Retired agricultural field • Disced – Summer 2003 • Machine planted with 1-0 loblolly – January, 2004 • Soil = clay loam

9. List of treatments in 2004 DuPont herbaceous weed control project Treatment No.1Herbicide and Rate/A (oz) 1 Matrix (2) 2 Matrix (4) 3 Steadfast (1) 4 Steadfast (2) 5 Oust Extra (2) 6 Oust Extra (3) 7 Matrix (2) + Oust Extra (2) 8 Steadfast (1) + Oust Extra (2) 9 Oust Extra (3) + Arsenal AC (4) 10 Oust Extra (2) + Arsenal AC (4) 11 Matrix (2) + Arsenal AC (4) 12 Steadfast (1) + Arsenal AC (4) 13 Arsenal AC (4) 14 Oust XP (2) + Arsenal AC (4) 15 Oustar (13) 16 Untreated 1Treatments 1,2,3,4,7, and 8 had Timbersurf 90 added (12.8 oz/A)

10. Application • CO2 –powered backpack sprayer • 4-nozzle boom with 8001 tips • 10 gpa • 5-foot bands centered over planted row • Dates of application • MS - April 13, 2004 • TX - April 5, 2004 • SC – April 14, 2004

11. Experimental Design • MS = RCB with 4 replications • SC = RCB with 4 replications • TX = RCB with 4 replications

12. Evaluation • Ocular evaluation of percent ground coverage at 30, 60, 90, and 120 DAT • Tree vigor at 30-day intervals • Initial height and groundline diameter (GLD) • Height and GLD - 1GSAT

13. Analysis • ANOVA • DNMRT

14. RESULTS

15. Major Herbaceous Species MS Bull paspalum*, panic grasses, Andropogon, late boneset, goldenrod, fireweed, common ragweed, dogfennel TX panic grasses, Chasmanthium, Paspalum, Andropogon, late boneset, common ragweed, dogfennel, purple cudweed SC perennial ryegrass, wild radish, Johnsongrass, common ragweed, panic grasses

17. 30 DAT

18. 30 DAT

19. 60 DAT

21. 30 DAT

22. 60 DAT

23. 60 DAT

24. 90 DAT

25. 120 DAT

26. 120 DAT

28. Summary • No treatments resulted in negative impact on loblolly seedlings • Only treatments to provide “best” control in all three states were Oust Extra + Arsenal AC combinations • Oustar and Oust XP + Arsenal AC treatments provided “best” control at two of three locations • Matrix and Steadfast did not provide acceptable control on these sites • Good to be able to test new products and/or applications, but sometimes, the answer is “no” • Oust Extra + Arsenal AC combinations provided excellent results on a wide variety of species