Fifteen tall, warm-season, native and ornamental grasses were subjected to a 3-year, low-input, and cold hardiness trial conducted from 2010 to 2013 in zone 4a at Fargo and Mandan, ND. Grasses tested were big bluestem [species (Andropogon gerardii)], ‘Pawnee’ big bluestem (A. gerardii), silver banner grass (Miscanthus sacchariflorus), giant miscanthus (Miscanthus ×giganteus), hardy pampas grass, (Saccharum ravennae), and the following maidengrass (Miscanthus sinensis) cultivars: Silver Feather, Narrow Leaf, Blondo, Autumn Light, Condensatus, Grosse Fontaine, Morning Light, Gracillimus, Strictus, and Zebrinus. In addition to survival, the grasses were also rated for spring vigor and fall quality (0–10 scale for both evaluations), fall leaf length, and fall flower height. The grasses received no management during the trial other than irrigation during the first season and weed control. The grasses were exposed to subsurface soil temperatures (at 6-inch depth) that reached as low as −8.6 °C at the Fargo location and −6 °C at the Mandan location. The study revealed that all big bluestem (species), ‘Pawnee’ big bluestem, and silver banner grass survived at both locations; silver banner grass scored the highest spring vigor ratings; silver banner grass and ‘Pawnee’ big bluestem scored the highest fall quality ratings; silver banner grass produced the longest fall leaf length; and ‘Pawnee’ big bluestem, big bluestem (species), and silver banner grass produced the tallest fall flowers.
Alan Zuk, Qi Zhang, Ted Helms and Harlene Hatterman-Valenti
Harlene M. Hatterman-Valenti, Collin P. Auwarter and Paul G. Mayland
Field trials were initiated during 2004 at a dryland site near Prosper, N.D., to evaluate the effects of simulated drift from glyphosate to `Russet Burbank' and `Red Lasoda' seed potato during the early senescence stage. Glyphosate was applied at rates 1/3, 1/6, 1/12, 1/24, and 1/48 the use rate for spring wheat desiccation on 10 Sept. 2004 with a CO2 pressurized sprayer operated at 280 L/ha and 276 kPa. The amount of a.m.S added to the spray solution was also reduced accordingly. Following harvest, samples from each plot were placed into cold storage until the following March. A subsample from each plot was slowly warmed to initiate sprout formation. Remaining samples were cut into 57-g pieces, dusted with a seed piece treatment, and stored at 18 °C with about 90% RH until planted. Plots consisted of two 3-m rows at 91 cm-row spacing with a border row on each side and three spacer plants between plots. The trial was arranged as a randomized complete block with four replications. Plots were desiccated on 12 and 19 Sept. and harvested 11 Oct. Tubers were hand-graded shortly after harvest. Results indicated that glyphosate at 70 g ae/ha or more inhibited tuber budbreak by 75% or more compared to untreated. In the field, injury was observed as delayed emergence and, in several instances, no plants emerged. Total yield for `Red Lasoda' was 34.8 Mg/ha for the untreated, which was significantly greater than glyphosate treatments of 280, 140, and 70 g ae/ha. `Russet Burbank' total yield was considerably less at 23.5 Mg/ha for the untreated. Both the untreated and glyphosate at 18 g ae/ha had significantly greater total yields compared with glyphosate treatments of 280, 140, and 70 g ae/ha.
Abigail R. Debner, Harlene Hatterman-Valenti and Fumiomi Takeda
Outdoor production of floricane-fruiting (FF) blackberry (Rubus subgenus Rubus) is problematic in the Northern Great Plains region of the United States because cane injury and plant death will occur from exposure to temperatures −15 °C and colder. An annual FF blackberry production system using hardwood floricane cuttings would overcome some of the existing limitations of traditional production methods. Several experiments were performed to induce adventitious root formation from one-node hardwood floricane blackberry cuttings taken in winter for the purpose of subsequent growth of a floral shoot. One-node hardwood cuttings of multiple blackberry cultivars (Apache, Arapaho, Kiowa, Osage, Ouachita, Siskiyou, and Triple Crown) were evaluated for rooting potential with and without auxin treatments. Root formation was virtually nonexistent for ‘Apache’, ‘Kiowa’, and ‘Triple Crown’ regardless of the auxin treatment. In general, lower auxin concentrations and the powder formulation produced more roots and had higher root ratings. However, rooting success of cuttings and plant development was low regardless of the rooting method used. Adventitious root production of one-node dormant hardwood FF blackberry cuttings for use in an annual production system had low success regardless of the cultivar, auxin application, rate, and formulation. The variable propagation success rates using single-node hardwood cuttings from ‘Apache’, ‘Arapaho’, ‘Kiowa’, ‘Osage’, ‘Ouachita’, ‘Siskiyou’, and ‘Triple Crown’ plants grown in containers in North Dakota suggested insufficient rooting success for the recommendation of this practice. Additionally, the results suggested these cultivars are not suitable using this method for an annual production system or as a means for large-scale propagation. Although this approach to developing plants from cuttings is of great interest, without a more effective FF blackberry cutting rooting method that can progress through fruit production, an annual blackberry production system in the Northern Great Plains region of the United States is unlikely.
Nagehan D. Köycü, John E. Stenger and Harlene M. Hatterman-Valenti
Elemental sulfur is commonly applied for powdery mildew (Erysiphe necator) protection on winegrape (Vitis sp.). The product may be used in a diversified, integrated disease management system to help prevent fungicide resistance to products with other modes of action. Additionally, sulfur may be used as a control option in organic systems. Applications of sulfur have been known to cause phytotoxic injury to susceptible winegrape cultivars, particularly those stemming from fox grape (Vitis labrusca) parentage. To improve recommendations to producers in the northern Great Plains region of the United States, a comparison of injury incidence and severity, as well as effects on yield characteristics was undertaken for 13 regional cultivars exposed to three sulfur rates (0, 2.4, and 4.8 lb/acre a.i.) at a North Dakota State University Research Station near Absaraka, ND. Overall, four cultivars (Bluebell, Baltica, Sabrevois, and King of the North) of the 13 cultivars tested showed phytotoxic symptoms. Injury severity and incidence of these cultivars differed between years and across rates. ‘Bluebell’ showed consistent and severe sulfur injury symptoms. Injury to the other three susceptible cultivars tended to vary by the given environment, with King of the North generally showing the lowest injury response. Injury symptoms were not found to be associated with the overall yield or cluster weight. Results suggest that alternative spray programs that exclude sulfur-based fungicides should be recommended for ‘Bluebell’, ‘Baltica’, ‘Sabrevois’, and ‘King of the North’, whereas sulfur-based fungicides may be applied to ‘Alpenglow’, ‘ES 12-6-18’, ‘Frontenac’, ‘Frontenac Gris’, ‘La Crescent’, ‘Marquette’, ‘Somerset Seedless’, ‘St. Croix’, and ‘Valiant’. Observations on fruit ripening in 2014 suggest that future research is needed to determine if a reduction of fruit quality may occur in some seasons with repeated sulfur applications or with successive annual sulfur applications for susceptible cultivars if used in an organic production system.
Harlene M. Hatterman-Valenti, Carrie E. Schumacher, Collin P. Auwarter and Paul E. Hendrickson
Field studies were conducted at Absaraka, Carrington, and Oakes, N.D., in 2005 to evaluate early season broadleaf weed control and onion (Allium cepa L.) injury with herbicides applied preemergence to the crop. DCPA is a common preemergence herbicide used in onion. However, DCPA can be uneconomical in most high-weed situations, or the usage may be restricted due to possible groundwater contamination. Potential substitutes evaluated were bromoxynil, dimethenamid-P, and pendimethalin. Main broadleaf weeds were redroot pigweed (Amaranthus retroflexus L.) and common lambsquarters (Chenopodium album L.). In general, all herbicides, except bromoxynil, provided acceptable broadleaf weed control 4 weeks after treatment. The highest herbicide rate provided greater weed control compared with the lowest rate for each herbicide. However, onion height was also reduced with the highest herbicide rate. In addition, the two highest rates of dimethenamid-P reduced the onion stand compared with the untreated. A postemergence application of bromoxynil + oxyfluorfen + pendimethalin to onion at the four- to five-leaf stage controlled the few broadleaf weeds that escaped the preemergence treatments and provided residual control of mid- and late-season germinating broadleaf weeds at two of the three locations. Intense germination of redroot pigweed during July at the Oakes location reduced onion yield with all treatments compared with the hand-weeded check. In contrast, total onion yields with all herbicide treatments except the high rate of dimethenamid-P were similar to the hand-weeded check at Absaraka and Carrington.
Sung Eun Lee, Chun Ho Pak, Yong Beom Lee, Harlene Hatterman-Valenti and Chiwon W. Lee
Afield study evaluated the influence of planting density on the yield and quality of confectionery seed pumpkins grown near Hatton, N.D. An open-pollinated selection of Chinese snow-white seeds (CS) and a hull-less (HL) seed cultivar (`Takai', Johnny's Selected Seeds) were grown at three different planting densities (1-, 2-, or 3-ft plant spacing on rows 5 ft apart) from 5 May to 7 Oct. The total number of plants at high, medium, and low densities was 8712, 4356, and 2904 per acre (21,529, 10,764, and 7176 plants per ha, respectively). The average number of fruits harvested at high, medium, and low densities, respectively, was 0.93, 1.2, and 1.4 per plant for CS and 1.2, 1.7, and 2.5 per plant for HL. Total seed yields were estimated at 1011, 599, and 466 kg/acre (2498, 1480, and 1151 kg·ha-1) for CS and 661, 500, and 498 kg/acre (1633, 1235, and 1231 kg·ha-1) for HL, respectively, at high, medium, and low planting densities. While the average weight of fruits decreased as planting density increased, the total number and weight of seeds produced per fruit were unaffected by changing plant density in either cultivar.
Harlene Hatterman-Valenti, Greg Endres, Brian Jenks, Michael Ostlie, Theresa Reinhardt, Andrew Robinson, John Stenger and Richard Zollinger
Field trials using sublethal doses of glyphosate, dicamba, or mixtures of both herbicides on dry edible pea (Pisum sativum), dry edible bean (Phaseolus vulgaris), and potato (Solanum tuberosum) were conducted at six locations to determine the injury potential if spray drift were to occur. All studies used three increasing sublethal doses of glyphosate and dicamba, which were labeled as low, medium, and high. The doses for each herbicide varied for the three crops because of expected sensitivity differences. Herbicide doses were targeted for the reproductive stage 1 with dry edible pea and dry edible bean, and at tuber initiation for potato. Visible injury 20 days after the treatment ranged from 0% to 13% for dry edible pea, 0% to 53% for dry edible bean, and 0% to 50% for potato. Compared with the nontreated, yield was least when doses included dicamba, regardless of the crop. Dry edible bean was the most sensitive crop to sublethal doses of dicamba, followed by dry edible pea and potato. Results from these six studies suggested that drift injury potential to dry edible pea, dry edible bean, and potato will be greater if a dicamba-resistant soybean (Glycine max) crop is adjacent and upwind compared with a glyphosate-resistant crop. Results also reinforce the need for diligence in the application of these herbicides in proximity to susceptible crops and the need to thoroughly clean sprayers before spraying a sensitive crop.