Various mechanical plus chemical weed control systems for dry bean production were evaluated at Carrington, ND and Crookston and Staples, MN during 1991 and 1992. A dozen tillage plus herbicide weed control systems are available to growers that can provide selective and effective weed control in dry beans without reliance on chloramben—a standard herbicide on dry beans that has been lost. Dry bean yields were similar with low or high level tillage treatments because most of the herbicide treatments with one cultivation gave adequate weed control and any additional tillage did not improve weed control. Kidney bean yields and prices were greater than either pinto or navy beans so the net returns (bean market value minus production costs) were much greater for kidney bean production. Dry bean producers in the North Central part of the U.S. have at their disposal dependable mechanical plus chemical weed control systems, and their market value has been sufficient to make dry bean production very economical in this region.

Weed removal experiments in dry edible beans were conducted during 1992 and 1993 at Crookston and Staples, MN. Ten manual weed removal treatments were studied to determine when a natural infestation of weeds first reduced dry bean yield, and when weed removal could be discontinued without further loss of seed yield. Major weeds in order of average biomass production on weedy check plots at dry bean harvest over locations and years were wild mustard, foxtail spp., redroot pigweed, common ragweed, wild buckwheat, hairy nightshade, and common lambsquarters. Hairy nightshade also emerged late in the growing season and could negatively affect harvest efficiency and stain navy beans. Weed removal treatments had little effect on dry bean stands or 100-seed weights of harvested dry bean seed. The critical period for weed control in dry beans was 3 to 5 or 6 weeks after planting (WAP). Thus, weed control practices should begin no later than 3 WAP and continue until at least 5 or 6 WAP for maximum dry bean yields.

Crop production questions and problems are usually best-addressed in a field setting. A 2-d field educational program was designed and conducted at the University of Minnesota Agricultural Experiment Station in Crookston. The primary objective was to educate participants in crop production management decisions via plot demonstrations. Five plot areas were designed to illustrate principles in five disciplines--weed management, soil fertility, crop morphology, entomology, and plant pathology. In each discipline's plot area, the instructors used combinations of demonstration plots, research plots, quizzes, lectures, and laboratory exercises to achieve their objectives. The administration of this program was comprised of state extension faculty, experiment station personnel, and area extension people. The budget was covered by tuition fees. Based on program evaluations, 71% of the respondents rated the overall program as excellent, and a majority of the respondents would like to have a similar program every year.

Certified seed potatoes were planted at the Northwest Experiment station on 11 May. Soils were of the Beardon silty clay loam type. Plots were four 40” wide rows, 25 ft in length. Treatments were arranged in a RCB design, replicated 4 times. Soil treatments were applied 2” above the seed piece and covered immediately with acceptably moist soil. Soil and foliar treatments were hand applied in 20 gal of total material per acre. All foliars were broadcast on 23, 30 June; 6, 15, 21, 28 July and 4 Aug. Dry chemicals were pre-weighed and all chemicals were mixed and sprayed in a single treatment mixture. All Asana 40WP treatments contained KW556-001 WSF, unless otherwise indicated. Early season had less than normal rainfall but from July, onward, plots often contained standing water. Yields were collected from the center 2 rows of each plot.

Certified B-size seed was planted on 26 May in a Bearden silt-loam dryland site. Soil moisture was considerably above normal. Plots were 4 40 inch rows 25 ft in length. Treatments were arranged in a RCB design and replicated 4 times. Admire was applied at planting time. Foliar treatments were applied in approximately 20/gal/acre using a hand-held CO2 sprayer and 40 psi. Foliar treatment dates were 29 June, 9 and 20 July, and 4 and 23 August. The initial application was delayed and defoliation was in excess of that normally used to initiate treatment. CPB populations were able to completely defoliate plants by the third week in July. Larval ratings were 0=none and 5≥50 per plant. Potato leafhopper ratings (0=none 5 = severe) were taken but appear to be uniform where potato plants were present. Late blight began to appear in the plots the second week of August. CPB populations were high and have been resistant to Asana XL in recent growing seasons.