Bermudagrass is a major forage species throughout Georgia and the Southeast. An essential part of achieving high-yielding, top-quality forages is proper weed control. Indaziflam is a residual herbicide that controls many broadleaf and grass species by inhibiting cellulose biosynthesis. Research conducted in Tift and Colquitt counties in Georgia determined optimal PRE rates for indaziflam for bermudagrass forage production. Treatments applied at spring greenup of established ‘Alicia’ bermudagrass included indaziflam at 47, 77, 155, or 234 g ai ha−1 PRE, pendimethalin at 4,480 g ha−1 PRE, a split application of indaziflam at 47 g ha−1 PRE followed by the same rate applied POST after the first cutting, and a nontreated control (seven treatments in all). Forages were machine harvested three times each year for each location beginning at least 47 d after treatment (DAT), with final cuttings up to 168 DAT. For all treatments, fresh- and dry-weight yields at each harvest and totals for the season did not differ from the nontreated control. Indaziflam at 155 and 234 g ha−1 did cause minor stunting at 44 DAT, but this was transient and not observed at the second harvest. Indaziflam applied PRE has the potential to provide residual control of troublesome weeds in bermudagrass forage and hay production, with ephemeral stunting at the recommended application rates.

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Oxidative stability is an important factor considered by those in the peanut manufacturing industry. Product stability has been shown to increase up to seven-fold when high-oleic peanuts are used. The percentage of US crop that is high-oleic continues to increase, but many producers are reluctant to grow high-oleic cultivars due to the uncertainty of the high-oleic effect on agronomic traits, such as seed germination, yield and grade. Experiments were designed and conducted to examine the effect of the high oleic trait on peanut seed germination in field plots and in the laboratory on a thermal gradient table. Genotypes used in these experiments included cultivars or breeding lines from each peanut market-type along with their near-isogenic, high oleic counterparts. Field emergence, or germination, was recorded in the field in 4 geographically different regions, as well as in the laboratory on a thermal gradient table. Thermal gradient table experimental results demonstrated a lag in germination in high oleic genotypes compared to their normal oleic counterparts in all market-types, but the effect was lowest in the runner-type pair. Results from these experiments increase the understanding of the agronomic properties of high-oleic peanut cultivars and could influence the modification of standard protocols used by state agencies to test high-oleic peanut germination for registered seed quality labeling. Furthermore, this study indicates that although producers may experience delayed germination from high oleic seed compared to low oleic counterparts, this germination lag is overcome by 21 days post-planting and does not negatively impact the agronomical performance of high oleic cultivars.

Numerous perennial horticultural crops are grown across the southeastern US. Blueberry and blackberry (also known as caneberry) are commonly found in roadside stands, promote agritourism with the pick your own markets, are important for fresh market commercial production in the region, and when processed, provide desirable value added products. Season-long weed control using residual herbicides is crucial for these perennial fruit crops to maximize berry quality and yield. Studies performed from 2012 to 2014 in Lanier and Clinch counties in Georgia evaluated the effects of repeated applications of indaziflam at 35, 75, or 145 g ai ha-1 applied biannually in March and September (5 total applications) on growth of ‘Alapaha’ rabbiteye and ‘Palmetto’ highbush blueberry, and ‘Apache’ thornless blackberry. All indaziflam treatments were mixed with glufosinate, and a glufosinate only treatment was included as a check. Minor leaf chlorosis (<10%) was noted within 30 days after application for all blueberries for all treatments, but this was always transient. Blueberry stem diameter was not different for any treatment, even when indaziflam was applied up to 725 g ai ha-1 over three years as compared to glufosinate alone. There was no chlorosis or stem diameter differences for blackberry noted for any treatment. Indaziflam applied in blueberry and blackberry production provides season-long control of numerous troublesome weed species, without causing injury or negatively impacting crop growth.

Peanut injury in the field can occur from flumioxazin applied PRE, but this is associated with plants that have emerged, or are about to, emerge from soil. The direct effect of flumioxazin on peanut seed germination and radicle development has not been evaluated. Therefore, research was conducted to determine peanut seed radicle development response to flumioxazin at different concentrations (0.0, 0.01, 0.10, 1.0 and 10.0 ppb) when tested at multiple temperatures (20, 23, 26, and 29 C) in laboratory experiments on a thermogradient table. Data analysis indicated that flumioxazin concentration was not different from the nontreated control (0.0 ppb) for 0.01, 0.1, and 1.0 ppb for peanut germination. Flumioxazin at 10.0 ppb was different from all other treatments and the nontreated control. However, comparing linear regression models for each flumioxazin concentration across all temperatures indicated no differences for slope. These data indicate that when there is direct peanut seed exposure to flumioxazin at field application rates, there is no impact on germination and radicle development. Temperature was noted to affect radicle development greater than field application rates of flumioxazin. As temperature decreased, germination and radicle length was inhibited or decreased, respectively.