Five cultivation implements (two flex-tine cultivators, brush hoe, and rolling and shovel cultivators) were evaluated for weed control and effect on broccoli, snap bean, and sweet corn yield. Each implement was used alone or in combination with flex-tine cultivators. Standard broadcast herbicide treatments were: broccoli, metolachlor at 2.3 kg ai/ha posttransplant; snap bean, metolachlor preemergence (PRE) at 2.3 kg ai/ha followed by fomesafen postemergence (POST) at 0.4 kg ai/ha; sweet corn, atrazine at 1.1 kg ai/ha plus metolachlor at 2.3 kg ai/ha PRE. In the snap bean trials, an additional treatment consisted of metolachlor at 2.3 kg ai/ha PRE applied in a 25-cm band over the crop row followed by fomesafen POST at 0.4 kg ai/ha directed at the crop row, with a subsequent shovel cultivation. In the sweet corn trials, all cultivation treatments received an application of atrazine at 1.1 kg ai/ha plus metolachlor at 2.3 kg ai/ha PRE in a 25-cm band over the crop row. In broccoli, weed control and yields with all cultivation treatments were comparable to those with broadcast herbicide. In snap bean, flex-tine cultivators failed to control weeds and prevent yield reductions compared to the broadcast herbicide treatment. When either the brush hoe or the shovel cultivator was preceded by flex-tine cultivation, weed control and snap bean yield were comparable to those with broadcast herbicides. Banded herbicides followed by shovel cultivation also controlled weeds and prevented yield reductions. In sweet corn, banded herbicides controlled in-row weeds, and despite variable between-row weed control, all cultivation treatments yielded as well as the broadcast herbicide treatment. Relative performance of the cultivators was influenced by soil type and rainfall as well as crop canopy characteristics.

Redroot pigweed and common lambsquarters control was variable within and between seasons when postemergence linuron and metribuzin were applied one or two times at below-labeled rates to one-, three-, or five-leaf carrots. A single, low-rate application of either herbicide at the one-or three-leaf stage of carrots failed to provide adequate season-long broadleaf weed control. Two low-rate applications to either one- + three- or three- + five-leaf carrots significantly improved control. Linuron produced little or no injury to carrots regardless of application timing. Metribuzininduced injury was variable initially and decreased to 10% or less by 14 d after treatment. One application of either linuron or metribuzin resulted in reduced yields of carrots.

Yellow cards coated with adhesive were used to survey for the presence, relative abundance and seasonal patterns of lady beetles in research and commercial fields of processing sweet corn in central and western New York in 1992 and 1993. The lady beetles species recorded, in order of abundance were: Coleomegilla maculata lengi Timberlake, Coccinella septempunctata L., Psyllobora vigintimaculata (Say), Hippodamia parenthesis (Say), Propylea quatuordecimpunctata (L.), Cycloneda munda (Say), Hippodamia glacialis glacialis (F.), Adalia bipunctata (L.), Coccinella trifasciata perplexa Mulsant, and Coccinella transversoguttata richardsoni Brown. Coleomegilla maculata lengi was in sufficient number to reflect seasonal patterns. Coleomegilla maculata lengi populations rapidly increased in early July, peaked in late July or early August and then rapidly declined. The timing of C. maculata lengi peak abundance was more closely related to day-of-year than to stage of crop development based on accumulated degree days from planting. The pattern of capture of C. maculata lengi at incremental distances into the field did not indicate colonization from the field edge.

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Experiments compared the effect on weed control and potato yield of banded applications of metolachlor plus linuron with or without flex-tine, rolling, and shovel cultivation prior to hilling. Cultivation without banded herbicide resulted in greater prehilling in- and between-row weed densities and reduced late-season weed control as compared to broadcast herbicides or cultivation with banded herbicides. Although the flex-tine and rolling cultivators were expected to provide improved in-row weed control, there were few differences between these and the other cultivation implements. Despite reduced weed control with cultivation alone, potato yields were not reduced.

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Seventy-six Cucurbita pepo L. cultivars and breeding lines were evaluated under field conditions for infestation levels and defoliation (leaf area consumed by beetles) by adult diabroticite beetles in 1992 and 1994. Striped and spotted cucumber beetles, Acalymma vittatum (F.) and Diabrotica undecimpunctata howardi Barber, respectively, were most common, but some western and northern corn rootworms, D. virgifera virgifera LeConte and D. barberi Smith and Lawrence, respectively, also were present. In general, pumpkin, delicata, acorn winter squash, scallop, and yellow straightneck summer squash types were the least infested and defoliated. Caserta/yellow, zucchini, caserta/zucchini, caserta, and precocious yellow straightneck types were the most infested and defoliated. The number of beetles per plant was correlated (r ≥ 0.72) with leaf defoliation and proportion of plants infested, indicating that beetle infestation is a good predictor of damage. The cultivars and breeding lines that were the least infested and defoliated can be used in breeding programs to develop desirable genotypes with reduced beetle preference. Conversely, those genotypes that were highly preferred have potential as trap crops for these beetle pests.