1. Summarizing 5 Years of Weed Management Research in Georgia 2001-2005 Eric P. Prostko Extension Weed Specialist and Tim L. Grey and William K. Vencill Research Weed Scientists

2. What have we done? 2001-2005 t63 field trials tMajor areas of emphasis è RR corn systems è LL corn systems è Accent vs. Option è harvest-aids è tropical spiderwort In-crop Post-harvest è other new products Aim Callisto, Lexar/Lumax

3. Should you use the RR corn system? t advantages èInexpensive èeasy èBroad spectrum èReduced drift concerns èNo soil insecticide issues tdisadvantages èNo residual èover-reliance on a single product èHerbicide resistance concerns èVolunteer in other RR crops

4. Texas Panicum Control At Harvest with Single or Split Applications of Roundup WM - II CN-04-04 (Attapulgus) Untreated Roundup WM @ 22 ozs/A 21 DAP Roundup WM @ 22 ozs/A 21 + 35 DAP

5. Corn Yield Response to Single or Split Applications of glyphosate (4.5 lb ae/gal) @ 22 ozs/A. Average of 6 irrigated locations (2003-05) DKC67-60RR

6. Glyphosate Resistance Around the World (8 species) t rigid ryegrass (1996) t goosegrass (1997) t horseweed (2000) t Italian ryegrass (2001) t hairy fleabane (2003) t buckhorn plantain (2003) t common ragweed (2004) t Palmer amaranth (2005) èIn Central Georgia * Can be found in US

7. 2005 GR-Pigweed Survey

8. Preserving the Value of Glyphosate t tank-mix 2,4-D in burndown when glyphosate will be used in-crop èConsider paraquat if appropriate t Alternate glyphosate use with other herbicide modes of action èTank-mix with atrazine in corn tUse other practices such as cultivation tDo not allow weed escapes to produce seed

9. Herbicide programs for managing glyphosate and ALS-resistant Palmer amaranth in Georgia field corn.

10. Texas Panicum Control OR

11. Accent vs Option Summary Texas Panicum Control t 8 field trials t Accent > Option è9 of 32 comparisons (28% of time) t Option > Accent è1 of 32 comparisons (3% of time) t Accent = Option è22 of 32 comparisons (69% of time) t No statistical differences in corn yield were observed in any trial!

12. Texas Panicum Control (104 DAT) - II Accent vs Option - 2004 CN-04-04 (Attapulgus) Applied 21 DAP PANTE = 1-2”, 2-4 leaf Untreated Accent @ 0.67 ozs/A Agrioil @ 1% v/v Option @ 1.5 ozs/A MSO @ 1.25% v/v AMS @ 3 lbs/A

13. Harvest-Aid Research

14. Harvest-Aid - 2004 Untreated Roundup WM @ 22 oz/A + Aim 2EC @ 1 oz/A + COC @ 1% v/v 15 DAT

15. Tropical spiderwort (a.k.a. Benghal dayflower) Commelina benghalensis ttropical Africa native tannual or perennial tseeds and rhizomes tabove and below ground flowers t1,600 seeds/plant talternate host of southern root-knot nematode tReservoir for southern stem blight (white mold)

16. TSW in Georgia * confirmed in 29 counties by GA Dept. of Ag and UGA in 2004 (blue) * identified in 4 more counties in 2005 (black)

17. Tropical Spiderwort Control in Field Corn - 2005 Untreated (166 bu/A) Aim 2EC @ 1.5 ozs/A Dual Magnum 7.62EC @ 1.33 pt/A Herbimax @ 1% v/v (168 bu/A) 34 DAT $24/A treatment cost (excluding application)

18. Post-Harvest – Field Corn (Our Achilles heel?)

19. Post-Harvest – 2005 2,4-D (1 pt/A) + Dual Magnum (12 ozs/A) + COC (1% v/v) 22 DAT 43 DAT 54 DAT * * * Grady County $12/A Treatment cost (excluding application)

20. The Future tLiberty Link? tProducts labeled but not yet tested in GA èImpact (AmVac) èStout (DuPont) tNew products being developed èKIH-485 tPost-harvest for tropical spiderwort tothers??

21. www.gaweed.com