Preemergence herbicide treatments metolachlor (Dual®) and pendimethalin (Prowl®) gave better than acceptable weed control ( >85 %) of prostrate and tumble pigweeds, puncturevine, common purslane, and groundcherry in cantaloupes. Preplant incorporated treatments provided less than adequate control of pigweeds and groundcherry. Bentazon (Basagran®) applied postemergence gave good control of pigweeds but groundcherry control was marginal. Napropamide (Devrinol®), trifluralin (Treflan®), and DCPA (Dacthal (D) caused cantaloupe stand reduction and injury. Bensulide (Prefar®) and Basagran® were safe when applied on cantaloupes.

Three commonly used herbicides for use in broccoli were effective when applied alone or in combinations as a preplant incorporated (PPI) or a preemergence (PE) application. DCPA (Dacthal®) at 10.0 lb product/A PE gave acceptable control of most weeds. Trifluralin (Treflan® SEC) at 1.0 pt/A and bensulide (Prefar® 4EC) PPI were also effective but mustard weeds were not adequately controlled. Combinations of the herbicides at lower rates did not provide any advantage in improving weed control efficacy.

Pre plant and pre- emergence herbicides are commonly used in lettuce production. We investigated possible effects the herbicides benefin (Balan), pronamide (Kerb) and bensulfide (Prefar) had on emergence and seedling growth of several iceberg lettuce varieties that had been primed and pelleted by seed enhancement companies The herbicide Prefar and a mixture of Balan + Prefar had the greatest impact on dry weight regardless of variety, while seedlings grown on Kerby plots were not significantly different than seedlings from untreated plots. Dry weight accumulation and field emergence were influenced significantly by pellet types and priming methods.

The sequence of preemergence (PREE) herbicide metolachlor (Dual II®) followed by postemergence (POST) herbicide mixture of primisulfuron plus prosulfuron (Exceed®) provided season-long near complete weed control in sweet corn. Preplant incorporated (PPI) treatments of dimethenamid (Frontier®), EPTC plus safener (Eradicane®), and herbicide mixture FOE 5043 plus metribuzin (Axiom®, Bayer) provided effective weed control for most of the season. Similar effective weed control was observed for PREE treatments of pendimethalin (Prowl®), Frontier, and Axiom.

An exploratory field study was conducted to evaluate the efficacy and safety of Nortron® (ethofumesate) herbicide for potential use in an onion weed control program. A rate range of 1.0 to 2.5 lb AI/A applied preemergence (PREE) demonstrated good safety on onions and no injury or crop stand reduction was observed. Sowthistle was the most numerous weed present and Nortron did not reduce it relative to the untreated check. Dacthal® (DCPA) significantly reduced the number of sowthistle relative to the untreated and to Nortron treatments. Onion height was reduced by Dacthal about 40 %.

Bentazon (Basagran®) at 0.5 to 2.0 lb a. i. /A, halosulfuron (Permit®) at 0.025 to 0.10 lb a.i A, and pyridate (Lentagran®) at 0.25 to 1.5 lb a.i. /A were applied postemergence on cantaloupe and watermelon. Bentazon was marginally safe on cantaloupes and controlled purslane and pigweeds. Morningglory and Wright's groundcherry were not effectively controlled by bentazon. Bentazon appeared to be less injurious to watermelons relative to cantaloupes. Halosulfuron was safe on both cantaloupes and watermelons (<15% injury). Halosulfuron at greater than 0.05 lb /A was effective in controlling only Hyssop spurge and London rocket. In one test, halosulfuron gave acceptable control (85 %) of morningglory. Purslane and groundcherry were not controlled by halosulfuron. Pyridate was not safe on cantaloupes causing severe crop stand reduction. Pyridate was safer on watermelons and caused marginally acceptable injury, however, weed control was not effective against groundcherry, spurge or London rocket. Pyridate appeared to give acceptable control of morningglory in one test.

Bensulide (Prefar®), clomazone (Command®), sulfentrazone (FMC), and halosulfuron (FMC) treatments applied preemergence (PREE) gave very good weed control of prostrate pigweed (Amaranthus blitoides), lambsquarters (Chenopodium album), and common purslane (Potulaca oleracea) at 5 weeks after treatment (WAT). Bentazon (Basagran ® and halosulfuron applied postemergence (POST) alone were marginally effective at less than 85% against the pigweed species at 2 WAT and controlled lambsquarters and common purslane. POST treatments following PREE treatments were highly effective to control most weeds. Watermelon injury was acceptable for Command and halosulfuron treatments. Basagran caused slight injury when applied POST on the watermelons. Carfentrazone was not effective against the weeds present in this test site and was safe on the crop. The greatest number of marketable watermelons were harvested from plots having treatments that provided effective weed control. Command plus Prefar PREE followed by Basagran POST and Prefar PREE followed by halosulfuron POST treated watermelons yielded high numbers of marketable fruit.

At three test sites, ethofumesate (Nortron®) at 1.0 and 2.0 lb AI /A was safe on onions. Nortron appeared to provide marginal control of light to moderate weed infestations of London rocket (Sisymbrium irio) at two sites. Pendimethalin (Prowl®) at 0.50 and 0.75 lb Al/A was safe on onions at two sites with furrow irrigation. At three sites with sprinkler irrigation, Prowl treatments caused as high as 62 to 88% stand reduction when sprinklers were used to incorporate the herbicide. Bensulide (Prefar0) injured onions at early rating dates and height measurements indicated that the plants were shortened relative to the untreated check. End of the season visual observations showed that onions had grown out of the initial injury and the crop did not appear to be damaged. Prefar combined with Prowl or Nortron was more injurious to onions with sprinkler irrigation than with furrow irrigated incorporation. Prefar gave marginal weed control in the tests under conditions with low weed infestations. Lactofen (Cobra®) was injurious to onions at all five test sites and caused significant crop stand reduction. Combination treatments of Prowl with DCPA (Dacthal®) or Prefar were damaging to onions under sprinklers but injury was minimal with furrow irrigations. Metolachlor (Dual®) and dimethenamid (Frontier®) caused minimal injury and no stand reduction of onions under sprinklers but with furrow irrigation, the stand was reduced and height reduction was substantial. The series of field tests demonstrated that herbicide performance was significantly influenced by irrigation practices. Prowl herbicide was extremely injurious and caused substantial crop stand reduction with sprinkler irrigation. Dual and Frontier exhibited less injury on onions under sprinklers than with furrow irrigation. Cobra at 0.25 lb AI /A was damaging to onions regardless of irrigation practice.

Season-long near complete weed control in sweet corn was achieved with preemergence (PREE) herbicide applications of pendimethalin (Prowl®), metolachlor (Dual®), or thiafluamide/metribuzin (Axiom®) followed by postemergence applications of bentazon (Basagran®) or dicamba (Banvel®). Basagran applied alone POST gave very good control ( >93 %) of lambsquarters (Chenopodium album) and purslane (Portulaca oleracea) but did not adequately control tumble pigweed (Amaranthus albus). Prowl applied alone PREE gave acceptable control of most weeds. POST applications of prosulfuron/primisulfuron (Exceed®) caused moderate corn injury by shortening internodes and overall plant height and slight foliar chlorosis.

Clomazone (Command®), bensulide (Prefar®), sulfentrazone, and halosulfuron treatments applied preemergence (PREE) provided very good control of prostrate pigweed (Amaranthus blitoides), lambsquarters (Chenopodium album), and common purslane (Portulaca oleracea) at better than 90% at 5 weeks after treatment (WAT). Halosulfuron was effective in controlling all weeds better than 90% at 7 WAT Carfentrazone was not effective against most of the weeds present in the test but appeared to be safe on cantaloupe. Postemergence (POST) treatments alone did not provide acceptable control of pigweeds but controlled lambsquarters and common purslane at 2 WAT. Halosulfuron and bentazon (Basagran®) applied POST following PREE treatments controlled most of the weeds better than 90% through 7 WAT. Cantaloupe yields were highest with good weed control provided by PREE treatments followed by POST herbicide applications. Basagran at 0.50 lb /A injured cantaloupe after applications but yields were not affected compared to the untreated check. Command, sulfentrazone, and halosulfuron caused cantaloupe injury after PREE applications. Basagran caused substantial crop injury after POST applications.