Metribuzin weeds controlled

The short list of chemicals represents only a small fraction of the inputs applied throughout North America. Lindane, malathion, MCPP, metolachlor, metribuzin, oryzalin, pendimethalin, and pronamide are just a few other of the dozens of formulations for insect and weed control available at any hardware or home maintenance store. All of them are toxic to some degree or another, and question marks hang over many of them as to the risk they may pose for people and the ambient environment. The potential hazards of each of the chemicals described above hints at the range of contemporary hazards associated with lawn care. 

On the other hand, the broad weed control spectrum of chloramben, which was introduced in 1959, brought with it widespread acceptance. As an over-the-row band for control of both broadleaf and grass weeds, cost was minimized. With good crop tolerance, chloramben dominated the early soybean herbicide market. During 1972, 85% of the product was applied as the granular formulation (Table 4.2). However, as application practices changed for the soybean crop, banded applications became an inconvenience. Herbicides such as metribuzin (a triazine herbicide), linuron, and bentazon, which could be applied as an affordable broadcast treatment, soon became products of choice, and the marketing of chloramben was eventually discontinued in 1990. 

Frear, D.S., E.R. Mansager, and H.R. Swanson (1981). N-glucoside conjugates Major metribuzin detoxification products in tomato. Presented to the North Central Weed Control Conference in Des Moines, Iowa. Miles Ag. Div. Report Number 80304.2... 

Many triazines have been evaluated for weed control in orchards and vineyards, but primary emphasis will be placed on simazine as the herbicide of preference in most of these crops. In general, simazine is better tolerated by most tree fruits, nuts, and vines than high rates of atrazine, prometryn, propazine, terbutryn, terbuthylazine, or metribuzin. 

Johnson, B.J. (1976c). Turfgrass tolerance and weed control with metribuzin and methazole. Weed Sci., 24 512-517. 

Fleming, G.F., L.M. Wax, F.W. Simmons, and A.S. Felsot (1992a). Movement of alachlor and metribuzin from controlled release formulations in a sandy soil. Weed Sci., 40 606-613. 

Worldwide there have been a total of 20 commercialized triazine herbicides. Of the 20 triazines, 7 are currently registered for land use within the United States ametryn, atrazine, metribuzin, prometryn, simazine, terbutryn, and prometon. For purposes of this discussion, only dietary estimates for the 5 most widely used domestic triazines are presented since the USEPA revoked cyanazine tolerances in 2004, prometon is not used for food crops and terbutryn has very limited use. Additionally, propazine was used under USEPA Section 18 registrations in the 1990s, and in 2007 was registered for weed control in sorghum (USEPA, 2007). 

Triazine herbicides are particularly well suited for conservation tillage because they provide foliar and residual control of a broad spectrum of weeds. Atrazine, simazine, and metribuzin are used in com, atrazine and propazine in sorghum, metribuzin in soybean, and simazine reduces tillage required for weed control in many perennial and tree crops. Atrazine is also used extensively in chemical fallow cropping systems in rotations involving corn, sorghum, and wheat. Cyanazine was also used extensively in corn and cotton until 2002. 

Currently no herbicides are cleared for use in the U.S. to control weeds in Jerusalem artichokes. Preliminary tests with several herbicides have been reported (Table 12.1). For example, the cultivar Columbia displayed satisfactory tolerance to preplant incorporated treatments of chloramben, S-ethyl dipropylthiocarbamate (EPTC), ethalfluralin, pendimethalin, and trifluralin, although metribuzin resulted in considerable damage, manifested as chlorosis and necrosis of leaf margins, and reduced plant height. Tuber yield, however, was not increased by weed control, whether via herbicides or hand weeding, when compared to weedy control treatments (Wall et al., 1987). 

Gianessi et al. [7] therefore compared the amount of glyphosate that had been used on herbicide tolerant soybeans in 2001 to the amoimt of mixed herbicides that would be required to achieve the same degree of weed control. For each U.S. state, an alternative mix of herbicides was composed for comparison, based on the outcomes of a survey among experts, e.g. a mix of Boimdary (metribuzin s-metolachlor), Flexstar (fome-safen), and Select (clethodim) in Iowa (Table 1). 

Sencor . [Bayer Miles/Ag] Metribuzin selecdve h icide fa weed control in potatoes, tomatoes, soybean, turf, etc. 

There are very few products which can be used post-emergence in potatoes. Metribuzin can be applied to some crops and varieties, as can the foliar-acting herbicides, bentazone and rimsulfuron. Several graminicides are approved for grass weed control, e.g. cycloxydim and propaquizafop. 

Baumley, J.J. and Ilnicki, R.D. (eds.) (1981) Combinations ofjlowable lignin and metribuzin for weed control in soya beans, Proc. Annual Meeting, Northeast Weed Science Society, MD, p. 52. 

Diquat, carfentrazone-ethyl, rimsulfuron or glufosinate-ammonium will kill most emerged seedling weeds. These chemicals work by contact action. Other residual heibicides (singly or in mixtures) can also be used, e.g. clomazone, linuron, flufenacet, or pendimethalin. Metribuzin is more persistent, but there are varietal restrictions. On organic soils it can be incorporated into the ridge to improve the control of weeds. 

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