We address whether it is better for a producer to own harvesting equipment or hire a custom harvester to perform the job. A comparison of calculated purchase costs with the cost of hiring a custom operator leads to an estimate of the break-even acreage, which is used as a decision criterion. However, two risk factors must be included in the decision process: the date of harvest and the efficiency of the harvest operation. The affect of these factors may significantly alter the “real” costs of owning vs. hiring a custom operator and, therefore, change the decision reached by an individual grower.
Steven C. Blank, Karen Klonsky and Kim Norris
Dong Sub Kim, Mark Hoffmann, Steven Kim, Bertha A. Scholler and Steven A. Fennimore
Steam has long been used to disinfest greenhouse soils. However, there is increasing interest in expanding the use of steam for in-field soil disinfestation as an alternative to chemical fumigants. Previous studies demonstrated that allyl-isothiocyanate (AITC) reduced viability of weed seeds and plant pathogen propagules, but AITC has a low vapor pressure and is relatively immobile in soil. Heat has been used in the past to enhance the mobility of soil fumigants such as methyl bromide (i.e., “hot gassing”). The effect of steam heat on the mobility of AITC is unknown. The objective of this study was to investigate the potential synergistic effect of steam plus ATIC against weed seeds and a plant pathogen. AITC alone did not reduce the viability of the four weed species and the number of Verticillium dahliae microsclerotia. The steam + AITC treatment reduced the viability of V. dahliae at 12.5 and 18 cm distances by 82% and 88%, respectively, and knotweed and nettle seeds at 70 cm from injection point by 75% and 86%, respectively, from the center of microplots compared with steam alone. The results suggest that AITC and steam have a complementary effect on soilborne pests because steam increases the mobility of AITC.
Michelle L. Jones, Eun-Sun Kim and Steven E. Newman
Geraniums are sensitive to ethylene during shipping and respond by abscising their petals. Treatment of stock plants with ethylene (ethephon) in order to increase cutting yield resulted in earlier flowering in Pelargonium × hortorum `Kim' and `Veronica', but did not result in increased susceptibility to petal abscission following exposure to 1.0 μL·L-1 ethylene. Treatment of `Kim', `Veronica', `Fox', and `Cotton Candy' with 1.0 μL·L-1 ethylene resulted in increased petal abscission within one hour, with `Fox' being the most sensitive and `Kim' the least. Pretreatment of florets with 1-MCP for 3, 6, 12, or 24 hours at concentrations of 0.1 or 1.0 μL·L-1 decreased petal abscission in all cultivars following exposure to 1.0 μL·L-1 ethylene. Treatment with 0.1 μL·L-1 1-MCP for 1 hour reduced petal abscission rates in ethylene treated florets to that of non-ethylene treated controls in all cultivars except Fox. `Fox' florets, which are more sensitive to ethylene, required 12 to 24 hours of exposure to 1-MCP to reduce petal abscission rates to that of control flowers. Pretreatment of geranium plants with 1-MCP can be used to reduce petal shattering during shipping. Chemical names used: 2-chloroethanephosphonic acid (ethephon); 1-methylcyclopropene (1-MCP).