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Grassy weed control in safflower, Williston 2004. (Riveland and Bradbury) 'Finch' safflower was planted on land cropped to durum wheat in 2003 using 7 inch rows at 30 lbs/a on May 15. The treatments were applied on June 16 to 4 to 6-leaf safflower, green foxtail 2-4 leaf and wild oats 4-6 leaf stage with 66 F, 42% RH, 5% clear sky and 3-6 mph W wind and dry topsoil at 70 F and dry plant surfaces. Russian thistle (1-2 inches tall), common lambsquarters (1 inch tall), and wild mustard (4-6 inches tall) were present. We used a small plot sprayer with wind cones, mounted on a G-Allis Chalmers tractor to apply the treatments, delivering 10 gals/a at 40 psi through 8001 flat fan nozzles to a 6.67 ft wide area the length of 10 by 25 ft plots. First rain received after application was 0.06 inches on June 26. The experiment was a randomized complete block design with four replications. Plots were evaluated for crop injury and weed control on August 17. Wild oat density averaged 1-5 plants/ft2 and green foxtail density averaged 10 plants\ft2. Safflower was machine harvested on October 14.

	Product	Crop	--Control--		Test		Seed
	Rate	inj.	Grft	Wioa	Weight	Yield	Oil
Treatment a	oz/a		%	%	lbs/bu	lba/	%
Poast+COC	8+1%vv	0	95	93	42.2	1224	33.0
Assurell+COC	8+1%vv	3	97	98	42.3	1117	33.2
Select+COC	8+1%vv	0	98	99	42.3	1138	33.7
Select+COC	12+1%vv	1	99	99	42.2	1343	33.8
Poast+COC	16+1%vv	0	97	98	42.7	1355	33.6
Select+COC	6+1%vv	0	99	99	42.2	1389	34.3
Select+HarmGT+COC	8+.2+1%vv	5	98	99	40.9	1544	33.9
Assure+HrmGT+COC	8+.2+1%vv	5	98	99	41.1	1546	32.6
Poast+HrmGT+COC	16+.2+1%vv	3	95	99	41.9	1553	33.4
Untreated	0	0	0	0	41.8	809	33.7
HIGH MEAN		5	99	99	42.7	1553	34.3
LOW MEAN		0	0	0	40.9	809	32.6
EXP MEAN		2	88	88	42.0	1302	33.5
C.V. %		147	2	3	1.4	15	1.9
LSD 5%		3	3	4	NS	288	NS
LSD 1%		NS	4	6	NS	389	NS
# OF REPS		4	4	3	2	4	2
F-TRT		3	939	478	1.8	6	1.2

a - COC = Petroleum Oil Concentrate; Herbimax from Loveland. HarmGT or HRMGT = Harmony GT

Summary: Minor crop injury was noted for any treatment combination containing Harmony GT. All treatments gave good control of green foxtail and wild oats, resulting in yield increases when compared to the weedy check. Harmony GT gave excellent control (not shown) of Russian thistle, common lambsquarters and wild mustard, and tended to increase yields over the grass herbicide treatments alone.