Thermal and ultraviolet loss of herbicides

Ionic liquid forms of the herbicide dicamba with increased efficacy and reduced volatility

“…10 Burnside et al 11 studied dicamba volatility under laboratory conditions, finding that as high as 29% of dicamba acid volatilized from planchets at 35 °C, after 7 days. Similar studies by Baur et al 12 reported 58% volatilization loss from glass beakers in 4 days at 30 °C.…”

“…18a However, Dow Agrosciences did not take into the account that there are a number of key differences between the usually higher volatility of protic ILs vs. aprotic ILs. For example, Baur et al 12 compared dimethylammonium dicamba herbicides (a protic cation) with tetramethylammonium dicamba (an aprotic cation) and found 70% injury to grapes from vapor exposure of [N(CH 3 ) 2 H 2 ] + salt vs. only 12% injury to grapes, with the [N(CH 3 ) 4 ] + salt. 12 With judicious selection of appropriate aprotic (so-called "permanent") biologically active cations, liquid salt forms might not only allow for modified physical properties, but also for dual functional performance 20,21 or even synergistic effects by the incorporation of two biologically active ions into a single IL.…”

Altitude Effects on Picloram Disappearance in Sunlight

“…However, Michel et al (16) reported marked effects of light intensities, but not temperatures' on picloram photodecomposition rates. Little effect of temperature on volatilization was observed by Bovey et al (3) or Baur et al (1) in their studies. Thus, temperature differences between the locations may not influence picloram loss rates.…”

“…The second set of experiments was done two times, once in July and once in August 1979 at Tucson. The dry picloram layer on 100 -mm -diam petri dish bottoms was obtained by the method described by Baur et al (1). The dishes were covered with a single layer of plastic film.…”

Foliar Absorption and Translocation of Dicamba from Aqueous Solution and Dicamba-Treated Soil Deposits

“…The commercial dimethylamine (DMA) 3 salt formulation of dicamba is considered to have low volatility (13). However, under field condi tions the DMA salt degrades to the free acid which volatilizes from leaves in sufficient concentrations to affect off-target plants (2).…”