Experiments in 1992Experiments in , 1993, and 1994 evaluated prohexadione calcium (calcium salt of 3,5-dioxo-4propionylcyclohexanecarboxylic acid) as a growth regu lator for peanut (Arachis hypogaea L.). Two experi ments in 1992 compared prohexadione calcium applied at 140 to 560 g ae/ha at the early pegging stage (PG) or at the row closure stage (RC). Greater suppression of main stem (MS) and cotyledonary lateral branch (CLB) length and greater row visibility at harvest were noted when prohexadione calcium was applied at RC. Prohexadione calcium applied at RC decreased MS and CLB length at harvest 16 to 27% and 14 to 29%, respec tively, and greatly improved row visibility. Prohexadione calcium applied at PG generally reduced yield and the percentage of extra large kertiels (ELK), fancy pods (FP), and total sound mature kernels (TSMK) buthadno effect on crop maturity. Prohexadione calcium applied at RC generally had no effect on yield or the proportion of TSMK but increased the percentage of ELK, de creased the percentage of FP, and enhanced crop matu rity. Two experiments in 1993 compared prohexadione calcium at rates of 47 to 280 g/ha applied at RC or at RC and again 3 wk later (RC3). Prohexadione calcium at 140 and 280 g/ha applied at RC suppressed MS and CLB length at harvest 11 to 18% and improved row visibility. Single and sequential applications were equally effec tive. Prohexadione calcium had no effect on yield, matu rity, or the percentage of ELK, FP, and TSMK in 1993. One experiment in 1994 compared prohexadione cal cium at rates of 186 to 280 g/ha applied at RC and RC3 or at RC and RC3 and 6 wk after RC (RC6). Results were similar with all treatments. MS and CLB length at harvest was reduced 29 to 34% and 28 to 32%, respec tively, and row visibility was greatly improved. Prohexadione calcium increased yield 8% and increased the percentage of ELK but had no effect on the percent age of FP and TSMK. Daminozide [butanedioic acid mono (2,2-dimethylhydrazide)] at 950 to 1430 g ae/ha was included in all experiments as a comparison. Row visibility and suppression of MS and CLB length at harvest in prohexadione calcium-treated peanut were at least as great as in daminozide-treated peanut. Results indicate prohexadione calcium could be an effectivereplacement for daminozide.

Field studies were conducted in 2011 and 2012 at the Sandhills Research Station near Jackson Springs, NC to determine the influence of weed-free strip width (WFSW) on newly planted ‘Navaho' blackberry plant growth, fruit yield, and fruit quality. Treatments consisted of 0-, 0.3-, 0.6-, 1.2-, 1.8-, and 2.4-m WFSW. Predicted blackberry yield increased from 718 to 1,015 kg ha−1at WFSW of 0 to 2.4 m. The currently recommended WFSW of 1.2 m resulted in a blackberry yield of 1,013 kg ha−1. Predicted individual blackberry fruit weight displayed a positive linear response to WFSW and increased from 3.1 to 3.6 g fruit−1at WFSW of 0 to 2.4 m. Soluble solids content (SSC) of dull black blackberry fruit was greatest (15.1 Brix) when WFSW was 0 m. Relative to a WFSW of 0 m, SSC was reduced 2.3 to 3.4% as WFSW increased from 0.3 to 2.4 m, respectively. WFSW did not influence shiny black blackberry fruit SSC, nor titratable acidity, sugar-to-acid ratio, or pH of shiny or dull black blackberry fruit or primocane number, length, and stem caliper.

A field experiment was conducted in 1996 and 1997 to determine snap bean tolerance to halosulfuron based on crop injury, height, and yield. Halosulfuron was applied preemergence (PRE), postemergence (POST), and sequentially PRE followed by (fb) POST at 35, 53, and 70 g ai/ha, respectively. For comparison, a hand-weeded check was included. When data were averaged across years and halosulfuron rates, halosulfuron PRE, POST, and PRE fb POST provided similar yellow nutsedge control (74 to 82%) at snap bean harvest. Halosulfuron PRE resulted in 4% snap bean injury at harvest. Similarly, halosulfuron PRE fb POST resulted in 5% injury, while halosulfuron POST caused the most damage at 8%. Snap bean height at harvest was reduced 14% with halosulfuron POST compared to the weed-free check, with only 5 and 6% reduction caused by halosulfuron PRE and PRE fb POST, respectively. Halosulfuron POST reduced yield 39% compared to the weed-free check, while the PRE and PRE fb POST application timings produced yield similar to the check. When averaged across years and halosulfuron application timings, an increase in halosulfuron rate had no effect on yellow nutsedge control or snap bean yield. A linear trend was found for snap bean injury and plant height at harvest with snap bean injury increasing with an increase in halosulfuron rate while snap bean plant height decreased with an increase in halosulfuron rate. Application of halosulfuron PRE is the safest means to control yellow nutsedge in snap bean in North Carolina.

Studies were conducted at six locations across North Carolina to determine tolerance of ‘Sunbelt’ grape (bunch grape) and muscadine grape (‘Carlos’, ‘Triumph’, ‘Summit’) to indaziflam herbicide. Treatments included indaziflam (0, 50, 73 g ai ha–1) or flumioxazin (213 g ai ha–1) applied alone in April, and sequential applications of indaziflam (36, 50, 73 g ai ha–1) or flumioxazin (213 g ai ha–1) applied in April followed by the same rate applied in June. No crop injury was observed across locations. Muscadine yield was not affected by herbicide treatments. Yield of ‘Sunbelt’ grape increased with sequential applications of indaziflam at 73 g ha–1 when compared to a single application of indaziflam at 50 g ha–1 or flumioxazin at 213 g ha–1 in 2015. Sequential applications of flumioxazin at 213 g ha–1 reduced ‘Sunbelt’ yield compared to a single application of indaziflam at 73 g ha–1 in 2016. Trunk cross-sectional area was unaffected by herbicide treatments. Fruit quality (soluble solids concentration, titratable acidity, and pH) for muscadine and bunch grape was not affected by herbicide treatments. Indaziflam was safe to use at registered rates and could be integrated into weed management programs for southern US vineyards.

Field experiments conducted in 1992 and 1993 evaluated transplanted watermelon tolerance to ethalfluralin applied PPI, PRE (before transplanting), and POST (immediately after transplanting) at 1.2 or 2.4 kg ai/ha. Other treatments for comparison included the registered herbicides ethalfluralin POST-directed spray (PDS), ethalfluralin PDS followed by (fb) naptalam POST, bensulide plus naptalam PPI, and a nontreated check. All treatments controlled common lambsquarters and goosegrass 83 to 100% 2 and 6 weeks after treatment (WAT). Watermelon was injured 30 to 77% in 1992 and 14 to 83% in 1993 by ethalfluralin PPI or PRE at 1.2 or 2.4 kg/ha. Ethalfluralin POST was not injurious to watermelon. In 1992, watermelon treated with ethalfluralin POST at 1.2 and 2.4 kg/ha yielded 52 to 62% more fruit than watermelon from the nontreated check. In 1993, yield of transplanted watermelon treated with ethalfluralin POST was similar to that in the nontreated check.