Four nitrogen (N) rates (0, 50, 100, and 150 lb/acre) were applied annually, and two spring vine-harvest methods (heavy pruning and mowing) were applied biennially in all combinations at one commercial ‘Stevens’ cranberry (Vaccinium macrocarpon) farm in southeastern Massachusetts for six consecutive years. Vine weights generated from each treatment combination were collected in Years 1, 3, and 5 (vine-harvest years). Mean vine weight across N treatments from the biennial pruning and mowing events was 1.4 and 3.6 tons/acre, respectively. Vine-harvest method affected yield components (number and weight of reproductive uprights) since mowed plots had values near zero in the vine-harvest year, and pruned vines were always productive. Increasing N rate increased overall vine weight produced. Pruned vines produced more marketable fruit than mowed vines in Year 4 and Year 6. Net income declined with increasing N rate (except Year 1). Averaged over 6 years, increasing N rate decreased net income of and had no effect on pruned and mowed vines, respectively. Although an alternate-year mowing program provides minimal opportunity for sustained vine recovery and would not be recommended for use over an extended period, mowing provided similar net income as heavy pruning (assuming income and/or cost savings from both vines and fruit) when 50 lb/acre N was applied. The incorporation of mowing, in conjunction with other cultural practices that manage the cranberry canopy and generate fruit, can be a viable economic option.
Hilary A. Sandler
The benefit of applying an antitranspirant for protection of cranberry (Vaccinium macrocarpon Ait.) vines exposed to desiccating conditions was evaluated at four different sites, two sites per year, for a period of 1 year each. Overall, plots receiving one fall application of an antitranspirant produced more berries and greater total fruit mass the following year than did nontreated plots. Overall dry leaf mass was not significantly affected. At one site, treated plots had more flowering uprights and more flowers per upright per unit of ground area than the nontreated plots. For cranberry growers who cannot maintain a winter flood, one fall application of pinolene (Vapor Gard) may offer some protection against winter injury. Further research is needed to document long-term yield effects as well as to clarify the role of the antitranspirant in protecting exposed vines and floral buds against adverse winter conditions. Chemical name used: di-1-p-menthene (pinolene).
Hilary A. Sandler and Carolyn J. DeMoranville
Four nitrogen rates (0, 50, 100, and 150 lb/acre) and four spring pruning severities (none, low, medium, and high) were applied annually in all combinations at two commercial ‘Stevens’ cranberry (Vaccinium macrocarpon) farms in southeastern Massachusetts for 4 years (consecutive). Because runners generated from pruning vines are used to establish new plantings, determining the vine weight generated from each treatment combination was an important criterion for the economic analysis; these data were collected each spring. Mean pruning weight across nitrogen treatments at both locations, collected from the low, medium, and high severity pruning treatments, was 0.17, 0.35, and 0.54 ton/acre, respectively. Economic analysis of the data indicated that nitrogen rate largely determined net income revenues; pruning severity did not significantly affect net income. Nitrogen rates of 100 and 150 lb/acre led to declines in fruit yield and ultimately, in net income. Annual removal of 0.5 ton of vines per acre while applying 50 lb/acre nitrogen did not negatively impact net income values over the 4-year study period. When deciding on horticultural management options for vine propagation, growers should consider the impact of their fertilizer program on fruit yield.
Hilary A. Sandler and Carolyn J. DeMoranville
Field conditions associated with commercial cranberry (Vaccinium macrocarpon Ait.) production were simulated in greenhouse studies to determine the effect of soil surface characteristics on dichlobenil activity. Sand was compared with organic matter, in the form of leaf litter, as the surface layer. A seedling bioassay using alfalfa (Medicago sativa L.), a dichlobenil-sensitive plant, was employed to determine root growth response on herbicide-treated soil. When the herbicide was applied to a sand surface, root growth was greater as time after application elapsed, indicating loss of herbicide activity. Conversely, the presence of organic matter on the surface prolonged the activity of the herbicide. Composition of the surface layer was more important than the depth of the layer in determining herbicide persistence. The influence of cultural practices, such as the application of sand or the removal of surface debris, on herbicide activity should be considered when planning weed management strategies for cranberry production. Chemical name used: 2,6-dichlorobenzonitrile (dichlobenil).
Mary Jane Else, Hilary A. Sandler and Scott Schluter
A system of mapping weed infestations in cranberries (Vaccinium macrocarpon Ait.) was developed that enables growers to incorporate integrated pest management practices into their weed control program. This system provides growers with information on the location of weeds and the area of weed patches, but differs from other weed mapping systems in that information on control priorities is included on the maps. Weed management efforts can then be directed to the most economically damaging weeds first. The mapping system also provides growers with a permanent record that can be used to communicate with staff and to evaluate weed management strategies.
Hilary A. Sandler, Carolyn J. DeMoranville and Wesley R. Autio
A 2-year field trial examined the interaction of nitrogen rate, vine density, and weed management options for establishing new cranberry (Vaccinium macrocarpon) plantings. Utilizing the vigorous hybrid, `Stevens', the cost-efficiency of the treatment combinations was evaluated by combining cranberry and weed biomass data with various economic estimates. The most cost-effective production scheme for establishing new cranberry beds is to plant vines at a low density, use moderate rates of nitrogen, and apply an annual application of a preemergence herbicide. This combination produced substantial vine coverage at very low cost, reduced weed biomass by 85% compared to untreated plots, and gave the best weed control per dollar spent. Growers may opt for other reasonably successful combinations that involve higher labor costs if they can produce their own cuttings (reducing initial costs) or if they are farming with the intent to reduce overall synthetic inputs.
Katherine M. Ghantous, Hilary A. Sandler, Wesley R. Autio and Peter Jeranyama
Damage and recovery responses of four cranberry varieties (‘Mullica Queen’, ‘Crimson Queen’, ‘Stevens’, and ‘Howes’) to handheld propane flame cultivation (FC) torches were evaluated. All combinations of four levels of exposure duration of three FC torches (open flame 0, 3, 6, and 9 seconds), infrared (IR) and IR with a 4.5-cm metal spike (0, 15, 30, and 45 seconds), were tested on rooted cranberry uprights (vertical stems) planted in clay pots. Pots were subjected to a single treatment from one FC torch at one exposure duration; a glyphosate wipe was also included as a treated control (industry standard). Treatments were replicated five times. All cranberry plants were damaged by all levels of exposure duration as evident by visual damage ratings, reduced net cumulative stem lengths, reduced number of uprights, and reduced proportion of reproductive uprights when compared with untreated plants. All cranberry plants treated with glyphosate had total mortality; all cranberry plants from all varieties treated with FC survived, and all had net positive stem growth in the year after treatment except for ‘Stevens’ treated with open flame and IR with spike. The non-fatal response of cranberry to FC indicates that FC will cause less damage than glyphosate to cranberry plants that are incidentally exposed during spot treatment of weeds and thus could be integrated into weed control in certain situations, including organic farming.
Laura K. Hunsberger, Wesley R. Autio, Carolyn J. DeMoranville and Hilary A. Sandler
Over a 2-year period, 11 cranberry (Vaccinium macrocarpon) farms in southeastern Massachusetts were selected to evaluate mechanical removal of swamp dodder (Cuscuta gronovii) with a conventional hand-held bamboo rake. This technique consisted of breaking and removing large strands of the parasite that connected host plants; embedded and encircled portions of the parasite were not removed. Differences in dodder biomass, cranberry yield, and berry weight were determined in plots that received zero, one, or two weed-removal events. Removing dodder one time per season reduced percentage of weed cover by more than 74% in both years. Impacts on dodder fresh and dry weight were not as discernible. Removal initially decreased dodder biomass, which remained 20% to 40% lower than the baseline values, but removal treatments did not differ statistically from the control. No additional benefits were obtained by removing the weed cover more than once. Biomass per berry was not affected by mechanical weed removal and fruit of marketable size were produced in the treated area. Substantial yield loss was largely attributable to the dodder infestations, but multiple removals may eventually reduce yield to levels below those associated with infestations alone.
Laura K. Hunsberger, Carolyn J. DeMoranville, Hilary A. Sandler and Wesley R. Autio
Uniformity of sand deposition on cranberry (Vaccinium macrocarpon) farms was examined to evaluate the potential use of two sanding methods to suppress swamp dodder (Cuscuta gronovii) seedling emergence by seed burial. During a 2-year study, 24 farms were evaluated with sand applied by either water barge or directly on ice. To measure the depth of sand deposited on the surface, soil cores were taken every 5 m in a grid pattern on a randomly selected portion of a commercial Massachusetts cranberry farm. Both application methods delivered nonuniform depositions of sand with the majority of the samples measuring less than the target depth. Surface diagrams depicting sand depths indicated no particular patterns of error or deposition that could be advantageously adjusted by the grower at the time of application. Mean actual: target depth ratios were 63% and 66% for barge and ice sanding, respectively (100% indicating actual equaled target). In the best scenario (two farms), 47% of the sanded area received less than the target amount; 11 farms had at least 90% of actual sand depths below the target depth. For farmers targeting 25-mm sand depths (depth expected to suppress dodder germination), the mean actual: target depth ratio was 58%, indicating half of the actual sand depths measured less than 15 mm. Compaction of the sand layer due to the elapsed time period (6 weeks or more) between sand application and measurement may have contributed to the large number of samples that were lower than the target depth. Even so, the irregularity of deposition patterns and the large proportion of sand depths that were less than 25 mm indicated adequate suppression of dodder seedling emergence would be unlikely with either sanding method.
Brett Suhayda, Carolyn J. DeMoranville, Hilary A. Sandler, Wesley R. Autio and Justine E. Vanden Heuvel
Sanding and pruning are two practices used in the cranberry (Vaccinium macrocarpon) industry for vine management and yield stimulation. This study compared varying levels of sanding and pruning on vine canopy characteristics, yield, and economic returns for two consecutive growing seasons. Each practice was applied in Apr. 2006 at four levels. Sand was applied directly onto the vines at four depths: control (0 cm), light (1.5 cm), moderate (3.0 cm), or heavy (4.5 cm); pruning was conducted at four severities with a commercial pruner: control (not pruned), light (one pass with the pruner), moderate (two passes), and heavy (three passes). Pruning levels had no effect on upright density over the two seasons, but the heavy sanding treatment decreased the number of uprights per unit area. For the first season only, light penetration to soil level increased linearly as severity increased for pruning and sanding. The number of reproductive uprights relative to total uprights decreased in the first year as severity increased for both practices. This effect continued in the second year for sanding treatments. Cumulative yield and net returns were higher in light severity treatments compared to those in the moderate and heavy treatments. Moderate and heavy sanding treatments were associated with lower yields and net returns than those for the untreated controls.