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Overview of Occurrence and Distribution of Pesticides in Relation to Use
Published in Steven J. Larson, Paul D. Capel, Michael S. Majewski, Pesticides in Surface Waters, 2019
Steven J. Larson, Paul D. Capel, Michael S. Majewski
The herbicides with highest use in the late 1970’s and early 1980’s were 2,4-D, picloram, and hexazinone. Use of these compounds has declined in recent years, however, and triclopyr is now the herbicide with highest use. Overall, there has been a significant decline in herbicide use over the last decade in the national forests. This is partially due to a 1984 ban on aerial application of herbicides in national forests and the increased costs of preparing the required environmental impact statements (Wehr and others, 1992). A number of national forests, particularly in the upper Midwest, have suspended all herbicide use for the past several years. The decline in herbicide use in the national forests has probably not occurred in other sectors of the forestry industry, although data on this are scarce.
Turfgrass Weeds and PGR Use
Published in L.B. (Bert) McCarty, Golf Turf Management, 2018
Clopyralid (Lontrel), triclopyr (Turflon), and various combinations with other herbicides also are alternatives to phenoxy herbicides for broadleaf weed control. Triclopyr belongs to the picolinic acid herbicide family. Compounds in this family are noted for their high degree of activity. These herbicides are up to 10 times more potent than 2,4-D on certain broadleaf weed species. They are rapidly absorbed by the roots and foliage of broadleaf plants, and are readily translocated throughout the plants via both xylem and phloem tissues. Problems with this herbicide family include its soil mobility and the extreme ornamental sensitivity. Clopyralid also is one of the newer members of this herbicide family. It is currently marketed in a mixture with triclopyr (Confront) for use on labeled cool- and warm-season turfgrasses. Clopyralid is especially effective on leguminous plants (nitrogen producing) such as black medic, clover, kudzu, lespedeza, and vetch. Penoxsulam (LockUp) is the most recently introduced broadleaf herbicide. It is noted for control of English daisy, Florida betony, and dollarweed and better turf tolerance. It is also formulated as a granule.
Physiological Energetics
Published in Alan G. Heath, Water Pollution and Fish Physiology, 2018
The herbicide triclopyr seems to act on fish in a manner similar to organochlorine insecticides. Johansen and Green (1990) quantified both muscular activity and oxygen consumption in coho salmon exposed for 96 h to trichlopyr. At a concentration <0.10 mg/L it caused hypersensitivity to external stimuli (such as lights being turned on) and elevated activity and oxygen consumption. At somewhat higher concentrations the fish became lethargic and oxygen consumption declined.
Evaluation of large-scale low-concentration 2,4-D treatments for Eurasian and hybrid watermilfoil control across multiple Wisconsin lakes
Published in Lake and Reservoir Management, 2018
Michelle E. Nault, Martha Barton, Jennifer Hauxwell, Eddie Heath, Tim Hoyman, Alison Mikulyuk, Michael D. Netherland, Scott Provost, John Skogerboe, Scott Van Egeren
Although there have been a variety of management techniques investigated for milfoil control (e.g., mechanical harvesting, biocontrol, hand-removal, bottom barriers), lake managers in Wisconsin have primarily relied on auxin-mimic herbicides, especially 2,4-D (2,4-dichlorophenoxy acetic acid), which is viewed as a selective and cost-effective management tool. In more recent years, 2,4-D and a variety of other auxin-mimic and systemic herbicides (e.g., triclopyr, fluridone) have been applied on a large scale (generally defined as >5% surface area) in efforts to provide long-term lakewide control of the target invasive species. The value in relating measured herbicide concentrations to long-term efficacy and selectivity following large-scale milfoil management efforts has been demonstrated in research with the aquatic herbicide fluridone (Getsinger et al. 2002, Madsen et al. 2002, Pedlow et al. 2006, Valley et al. 2006, Wagner et al. 2007, Parsons et al. 2009) and triclopyr (Netherland and Jones 2015). However, very little literature is currently available on the effects of large-scale management utilizing 2,4-D.
Sediment-associated organopollutants, metals and nutrients in the Nechako River, British Columbia: a current study with a synthesis of historical data
Published in Canadian Water Resources Journal / Revue canadienne des ressources hydriques, 2019
Philip N. Owens, David J. Gateuille, Ellen L. Petticrew, Barry P. Booth, Todd D. French
Phenoxy acid herbicide (triclopyr, bromoxynil, clopyralid, 2,4-D, dicamba, 2,4-DB, 2,4-DP [dichlorprop], dinoseb, MCPA, MCPB, mecoprop, picloram, 2,4,5-T, and 2,4,5-TP) determinations in bottom sediment were done by ALS Environmental Ltd (Burnaby, BC) in collaboration with AXYS. Per ALS Method L1856769, 5-g samples were mixed with methanol, acidified and extracted with toluene; derivatized extracts were analyzed by capillary column GC-MS. Samples were run in batches of 20; each batch included a method blank based on Baked Ottawa Sand, a laboratory control and duplicate, phenoxy acid herbicide surrogates, a sample split duplicate, and a phenoxy acid herbicide matrix spike.