The response of wild garlic (Allium vineale L. # ALLVI) to fall and spring applications of chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) amino] carbonyl] benzenesulfonamide} was evaluated in the field in 1982 and 1983. In natural stands, application of 20 g ai/ha in the spring reduced aerial bulblet production by 99%. Applications in the fall were much less effective (20 g/ha reduced aerial bulblet production by 59%), but were still better than the standard treatment of 2,4-D applied in the spring (840 g ae/ha reduced aerial bulblet production by only 45%). In planted stands, chlorsulfuron was applied preemergence at two locations at 10 and 20 g/ha in the fall, and postemergence in early fall, late fall, early spring, and late spring. All treatments reduced aerial and underground bulb production, but spring applications were much more effective than any of the fall treatments. Application of 20 g/ha of chlorsulfuron in late spring (mid-to-late April) reduced aerial and underground bulb production by greater than 95%. At this time the old bulb reserves were exhausted, and the scape and new bulbs were at an early and rapid stage of development.

Experiments were conducted to evaluate imazaquin and selected herbicides for POST control of wild garlic. At the same dosages, imazaquin applied in late November/early December (late fall) controlled wild garlic better than when applied in early March (late winter) when assessed in May. Imazaquin provided control equivalent to 1120 g ae ha–1 2,4-D plus imazaquin. Imazapyr, imazamethabenz, or imazethapyr at 280, 1120, or 560 g ai ha–1, respectively, provided control equivalent to 560 g ai ha–1 imazaquin. Thifensulfuron at 70 g ai ha–1 provided better control applied in late winter (85%) than late fall (45%). All herbicides consistently provided better control than 2,4-D plus mecoprop plus dicamba, except thifensulfuron applied in late fall, at the final evaluation. Common bermudagrass growth in early spring was delayed 2 mo by ≥ 560 g ha–1 imazaquin, 70 g ha–1 thifensulfuron, imazethapyr, and imazapyr or 2,4-D plus mecoprop plus dicamba applied in late winter. Imazamethabenz did not delay common bermudagrass growth. Late fall applications of 1120 g ha–1 imazaquin did not delay growth while ≥ 560 g ha–1 imazethapyr delayed common bermudagrass growth through April.

Field studies were conducted over 2 yr and two locations per year in soft red winter wheat to determine the efficacy of thifensulfuron and thifensulfuron plus DPX-L5300 (2:1 ratio) on all wild garlic reproductive bulbs. The herbicide formulations controlled wild garlic equally. Aerial bulblet control was excellent (>90%) with either herbicide regardless of application timing (March 21, April 8, and April 29) and significantly better than the standard treatment of the butoxyethanol ester of 2,4-D. Control of developing underground offset bulbs was less complete compared to aerial bulblets, and was found to depend on application time. Offset bulbs were controlled better when herbicides were applied in late March or early April compared to the April 29 treatment date. The rate response (9 to 70 g ha-1) was positive for the control offset bulb production at the two earlier dates but not at April 29. These herbicides also adversely affected the germination and viability of the bulbs that were produced.

Chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl] benzenesulfonamide} was evaluated for weed control in winter wheat (Triticum aestivum L.) and for residual effect on soybeans [Glycine max (L.) Merr.] following wheat. Chlorsulfuron applied at 72 g ai/ha and less did not injure or reduce grain yields of ‘Double-Cropped’ wheat. Postemergence tank mixtures of chlorsulfuron at 36 g/ha with diclofop {(±)-2-[4-(2,4-dichlorophenoxy)phenoxy] propanoic acid} at 1 kg/ha were more effective than other treatments for control of wild garlic (Allium vineale L. ♯ ALLVI). ‘Forrest’ soybeans did not show any injury from chlorsulfuron residue even at rates of 72 g/ha when it was no-till seeded following winter wheat.

The absorption and translocation patterns of foliar applied 14C- chlorsulfuron {2-chloro-N- [[(4-methoxy-6-methyl-1,3,5- triazin- 2 - yl)amino] carbonyl] benzenesulfon-amide} and 14C-metsulfuron {2- [[[[(4-methoxy-6-methyl-1,3,5- triazin- 2-yl)amino] carbonyl] amino] sulfonyl] benzoic acid} in wild garlic (Allium vineale L. # ALLVI) were similar. Both 14C-chlorsulfuron and l4C-metsulfuron were readily absorbed by wild garlic, with 62 and 58%, respectively, of the applied doses absorbed 144 h after application. After 144 h, 17% of the applied 14C-chlorsulfuron and 16% of the applied 14C-metsulfuron were translocated out of the treated leaf, with the greatest amounts concentrating in young shoot tissues. Chlorsulfuron and metsulfuron reduced wild garlic shoot dry weight, height, and the number of leaves, more when they were applied to the foliage, or to both the foliage and the soil, than when they were applied to the soil alone.