Few published studies exist documenting banana pepper tolerance to clomazone. Therefore, field trials were conducted in 2022 at two Indiana locations [Meigs Horticulture Research Farm and the Pinney Purdue Agricultural Center (PPAC)] to evaluate crop safety in plasticulture-grown banana pepper. The experimental design was a split-plot in which the main plot factor was the clomazone rate (0, 840, and 1,680 g ai ha–1) and the subplot factor was cultivar (‘Pageant’ and ‘Sweet Sunset’). Clomazone was applied over the top of black polyethylene mulch-covered raised beds and their respective bare-ground row middles 1 d prior to transplanting 12 pepper plants per subplot. Data collected included crop injury on a scale from 0% (no injury) to 100% (crop death) at 2, 4, and 6 wk after treatment (WAT), and plant stand. Two harvests were performed in which mature fruits were counted and weighed. Injury presented as interveinal bleaching only at PPAC 2 and 4 WAT. At this location 1,680 g ha–1 clomazone resulted in greater injury to ‘Sweet Sunset’ at 2 and 4 WAT (53% and 15%, respectively) than to ‘Pageant’ (19% and 3%, respectively); however, plant stand and yield were not affected by either clomazone rate. These results suggest that the clomazone rate range currently used for bell pepper (280 to 1,120 g ai ha–1) can be applied prior to transplanting plasticulture-grown banana pepper with minimal crop injury and without reducing yield.

Chlorsulfuron, thifensulfuron, bromoxynil, 2,4-D, glyphosate, and a combination of 2,4-D plus glyphosate were applied on newly planted and established ‘Lemberger’ wine grape at 1/3, 1/10, 1/33, and 1/100 of the maximum labelled rate in wheat or fallow to simulate exposure to drifted herbicides. All herbicides produced symptoms on grape but the most severe symptoms were with 2,4-D and the least severe with bromoxynil. Newly planted grape was more sensitive to herbicides than established grape. Although established grape recovered from injury caused by all treatments except 2,4-D and the highest rate of chlorsulfuron and glyphosate, newly planted grape recovered only from lower rates of bromoxynil. All herbicides resulted in diagnostic symptoms, but other symptoms were very similar to those caused by other stresses.

‘Vernal’ alfalfa response was evaluated when chlorsulfuron, thifensulfuron, 2,4-D, glyphosate, bromoxynil, and selected combinations of those herbicides were applied at rates simulating spray drift during the fourth trifoliolate leaf stage following the first cutting in 1990 and 1991. The order of phytotoxicity was 2,4-D > chlorsulfuron > thifensulfuron > glyphosate > bromoxynil. By the end of each growing season, alfalfa had recovered from injury caused by all herbicides except the highest rates of 2,4-D and 2,4-D plus glyphosate. The alfalfa stand was reduced only by 2,4-D and 2,4-D plus glyphosate. All herbicides caused characteristic symptoms, but some specific symptoms were similar among different herbicides or resembled symptoms caused by disease, mineral imbalance, and adverse weather conditions.

‘Lemberger’ wine grape response to fall application of selected herbicides applied at simulated drift rates was studied in 1992 and 1993. Chlorsulfuron, thifensulfuron, 2,4-D, glyphosate, bromoxynil, and 2,4-D plus glyphosate were applied at 1/100, 1/33, 1/10, and 1/3 of a selected maximum rate for use in wheat or fallow. All herbicides, except bromoxynil and thifensufluron, caused symptoms on grapevines at the highest rate during the spring following fall application. The most severe symptoms were caused by 2,4-D and 2,4-D plus glyphosate, whereas the least symptoms were caused by chlorsulfuron and glyphosate. The severity of symptoms increased and shoot growth, leaf area, internode length, and dry cane weight decreased as the rates of 2,4-D and 2,4-D plus glyphosate increased. Chlorsulfuron and glyphosate reduced the growth of grapevines only when applied at the highest rate during the fall. The data show that exposure of wine grapes to 2,4-D or 2,4-D plus glyphosate during the fall can adversely affect the growth of grapevines the following spring.

This study was designed to develop a protocol for using a biologically-based system to detect and tract airborne herbicides. Common bean, lentil, and pea were selected for their quasi-diagnostic sensitivity to chlorsulfuron, thifensulfuron, metsulfuron, tribenuron, paraquat, glyphosate, bromoxynil, 2,4-D, and dicamba. Plants were grown in the greenhouse at Prosser, WA, and placed at 25 exposure sites at weekly intervals between Apr. 2 and Oct. 15, 1991. After 1 wk of field exposure plants were brought back and observed for herbicide symptoms over a 28-d period. Symptoms that developed were compared with symptoms caused by disease, insects, adverse weather conditions, and herbicides applied at different rates under controlled conditions on these species. In addition, if herbicide symptoms were observed, herbicide spray records and weather data in the area were used in a computer model to determine the source of potential herbicide drift. This study demonstrates that indicator plant species selected for high sensitivity to herbicides can be used to monitor the occurrence of herbicide movement.

‘Lemberger’ wine grape response was evaluated when chlorsulfuron, tribenuron, thifensulfuron, chlorsulfuron plus metsulfuron, thifensulfuron plus tribenuron, and 2,4-D were applied up to three times at weekly intervals in 1992 and 1993 at rates simulating drift. All herbicides injured grapevines visibly. Symptoms increased and total leaf area and grape pruning weight decreased as the herbicide rate and number of applications increased. Grapevines generally recovered within 45 to 60 d from symptoms caused by single exposures to low levels of sulfonylurea herbicides. Multiple exposures of grapevines to 2,4-D, tribenuron, and chlorsulfuron plus metsulfuron at 1/100 of the maximum use rate for wheat caused the greatest injury, which persisted throughout the entire growing season and reduced pruning weight. Based on potential use rate, the order of herbicide phytotoxicity was 2,4-D > tribenuron > chlorsulfuron plus metsulfuron > thifensulfuron plus tribenuron > chlorsulfuron > thifensulfuron. Rates that slightly injured grapevines did not reduce growth as measured by pruning weight. However, multiple exposure to high rates of 2,4-D, tribenuron, and chlorsulfuron plus metsulfuron adversely affected growth.

Field experiments were conducted at Hays and Manhattan, KS, in 2002 and 2003 to determine winter wheat response to simulated drift rates of glyphosate and imazamox. Glyphosate and imazamox at 1/100×, 1/33×, 1/10×, and 1/3× of usage rates of 840 g ae/ha glyphosate and 35 g/ha imzamox were applied individually to wheat in the early jointing or the early flower stages of growth. Wheat injury and yield loss increased as herbicide rate was increased, with minimal effect from either herbicide at the 1/100× rate, and nearly complete kill and yield loss of wheat from both herbicides applied at the 1/3× rate, regardless of growth stage at application. In general, wheat injury and yield reduction were greater from glyphosate than from imazamox. In addition, wheat injury and yield loss were greater from herbicide treatment at the jointing stage than at the flowering stage of development. Correlation analysis suggests that visual injury is an accurate indicator of yield reductions. Germination tests of harvested grain showed that the viability of the wheat seed was not reduced if plants survived the herbicide treatment and produced a harvestable seed.

Field experiments were conducted at four locations in Kansas in 1999 and 2000 to evaluate grain sorghum response to simulated drift rates of four herbicides. Imazethapyr, glufosinate, glyphosate, and sethoxydim were applied at 1/3, 1/10, 1/33, and 1/100 of the use rate when plants were 10 to 20 cm tall. Visible crop injury increased as rates of each herbicide increased. Glyphosate and imazethapyr caused the most injury and glufosinate the least. Data show that some plants that were significantly injured 2 wk after treatment (WAT) recovered 8 WAT. However, some plants that received the highest rate of imazethapyr or glyphosate died. Grain sorghum yields were reduced only when injury was severe. This research showed that the potential for sorghum injury from off-target herbicide drift is greater from imazethapyr and glyphosate than from sethoxydim or glufosinate.