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‘Coy’ alder-leaf mountain mahogany (Cercocarpus montanus) is a new cultivar developed from a species native to the western United States with potential for use in xeriscaping, rock gardens, and water-efficient landscaping. However, efficient propagation methods are not well developed for it. In this study, cutting propagation of ‘Coy’ alder-leaf mountain mahogany was investigated over 3 years to evaluate the effects of wounding method, rooting hormone, type of cuttings collected, and time for cutting collection on rooting. In May, Jul, and Sep 2020, 2021, and 2022, nondormant hardwood subterminal cuttings and/or semihardwood terminal cuttings were collected for wounding studies. Before the treatment with 3000 mg·L⁻¹ indole-3-butyric acid (IBA) in powder, cuttings were wounded either by scraping one side (scrape) or by perpendicular cuts around the base (cut), and cuttings without additional wounding were used as the control. Similarly, subterminal and terminal cuttings of ‘Coy’ alder-leaf mountain mahogany were collected during the same time and were used for hormone treatments. Cuttings were treated with 1000 or 3000 mg·L⁻¹ IBA in powder or 1000/500 or 3000/1500 mg·L⁻¹ IBA/NAA (1-naphthaleneacetic acid) in solution. Wounding by cut or scrape increased the rooting percentage. In addition, most cuttings wounded by the scrape method had better rooting than those wounded with cuts. On the basis of hierarchical cluster analyses, cuttings treated with 3000 mg·L⁻¹ IBA in powder had greater rooting than those treated with other hormones. Therefore, our research showed that successful rooting of subterminal or terminal stem cuttings of ‘Coy’ alder-leaf mountain mahogany can be achieved through wounding using scrape method and by treatment with 3000 mg·L⁻¹ IBA in powder.

The University of Connecticut Extension Sustainable Landscapes program seeks to develop an invasive plant training program to equip stakeholder groups of varied experiential backgrounds with the information needed to evaluate, manage, and mitigate populations of invasive species in Connecticut. A mixed methods needs assessment was conducted to explore diverse viewpoints about invasive plant education. Data were collected from 233 survey respondents and three focus group interviews. Landscape professional/contractors and municipal employees totaled 41.1% of respondents when combined, and home gardeners totaled 27.9%. The greatest programmatic need identified by survey respondents was invasive plant management options and strategies, with Japanese knotweed considered the most problematic invasive plant from a list of 16 species. Focus group participants expressed enthusiasm about targeted educational programming, such as efforts focused on land management principles, species identification, state regulatory agencies, and pesticide application. Many shared the need for enhanced public education efforts and resource availability. A hybrid approach, including virtual and in-person components, was recommended as the ideal delivery modality for an invasive plant training program.

Drought and salinity affect turfgrass growth and development adversely. Plant growth-promoting microorganisms (PGPMs) have been shown to have the capability of improving resistance to biotic stressors in plants. The objective of this research was to determine the efficacy of six commercial PGPMs on enhancing the drought and salinity resistance of kentucky bluegrass (Poa pratensis). The six PGPMs evaluated were Beauveria bassiana (strain GHA), Bacillus subtilis (strain GB03), Azadirachtin, Bacillus firmus (strain 1-582), Trichoderma harzianum Rifai (strain T-22) combined with Trichoderma virens (strain G-41), and Bacillus subtilis (strain QST713). Three cultivars—Kenblue, Moonlight, and Waterworks—were seeded in the greenhouse. Two-week seedlings were exposed to saline (sodium chloride at 6 dS⋅m^–1 three times per week) or drought (tap water once per week) conditions, and no stress (irrigated with tap water three times per week) for 4 weeks. Results show that drought and salinity inhibited turf growth, with the greatest reduction in root dry weight (50.3% in drought conditions and 31.4% in saline conditions). ‘Kenblue’ performed better than ‘Waterworks’ and ‘Moonlight’ in all growth indices except for root length. Beauveria bassiana and B. subtilis had a similar or better result in enhancing turfgrass growth and development compared with the untreated turf under stress. Our results suggest that certain PGPMs have the potential to improve abiotic stress resistance in turfgrass.

Thirty sweetpotato (Ipomoea batatas var. batatas) genotypes were evaluated for yield, resistances to weevil or nematode pests, and consumer acceptance across three field trials planted at Pepe‘ekeo, Hawai‘i Island between 2017 to 2020. At harvest, storage roots were graded according to market standards, followed by scoring for damage by sweetpotato weevil (Cylas formicarius elegantulus), rough sweetpotato weevil (Blosyrus asellus), or nematodes; namely root-knot nematode (Meloidogyne spp.) or reniform nematode (Rotylenchus reniformis) in each market class. There were significant differences in marketable yields among accessions when data were analyzed statistically across all three field trials, as well as individually. ‘Regal’ (PI 566650) and ‘Sumor’ (PI 566657) were among the top three highest-yielding genotypes for Trials 1 and 2 (when no insecticides were applied to control weevils), and among the top six highest-yielding genotypes for the joint analysis across three trials. Significant differences among genotypes for combined sweetpotato weevil damage (incidence of sweetpotato weevil alone or incidence of both weevils together) were found in the joint analysis across three trials. ‘Regal’ was among the lowest seven genotypes for combined sweetpotato weevil damage, supporting earlier reports of its moderate resistance to this pest. In addition, two genotypes produced by the World Vegetable Center (Shanhua, Taiwan) (WT-320 and WT-108), were among the lowest genotypes for combined sweetpotato weevil damage, in agreement with earlier reports of their substantial resistance to this pest. Providing access to diverse germplasm will help farmers react to increasing pest pressure, while still allowing for high marketable yields. In addition, breeding and selection for pest resistance could be an important addition to integrated pest management of sweetpotato in Hawai‘i.

The nursery industry produces and sells plants for landscape and environmental purposes and represents a major sector within the US agricultural industry. In recent years, the nursery industry has undergone rapid growth as a result of various factors, including increased demand from housing development and pandemic-fueled interest in home horticulture. As with any industry, the nursery industry must adapt to changes in societal trends to sustain growth. In the wake of unprecedented societal and supply chain issues stemming from the global coronavirus disease 2019 pandemic, the American Society for Horticultural Science Nursery Crops Professional Interest Group gathered experts in various disciplines to provide their opinions and insights into the future of the nursery industry, focusing specifically on the changes and challenges the nursery industry will face in the coming decade. Nursery crop specialists spanning the United States identified three primary areas that will steer the future momentum of the nursery industry: consumer trends, natural resources, and labor. Six experts were selected to represent these areas in a workshop held Jul 2022 at the American Society for Horticultural Science Annual Conference in Chicago, IL, USA. This article was developed to disseminate to the greater scientific community the discussions held and insight shared during that workshop.

Turfgrass seed, a living organism, is facing more stringent trade regulations compared with nonliving products. We applied multiple empirical approaches to explore the impact of these regulations on trade flows in grass seeds. We constructed a series of novel variables to measure these regulations, such as environment regulation stringency, pre-shipment inspections, market conditions, and product requirements. Our results showed that nontariff trade measures had substantial impacts on the trade of grass seeds. These measures sometimes worked as barriers to trade and at other times worked as catalysts for trade.

In temperate climates, aquaponic producers must use artificial lighting; however, purchasing light-emitting diode (LED) grow lights can be cost-prohibitive. Two aquaponic trials evaluated low-cost LED lighting for the growth of bibb lettuce (Lactuca sativa var. capitata). In trial 1, seven low-cost LED lights were screened and compared with a high-end LED grow light. The three best-performing lights in terms of total plant biomass produced (grams) and total plant biomass per unit of electricity (grams per square meter per kilowatt-hour) were more intensively evaluated in trial 2. These lights included Spider Farmer SF-2000 [SPI ($300)], Fluence RAZRx [FLU ($364)], Designers Fountain 6-Light 5000 K LED High Bay Light [DES ($100)], and the control NeoSol DS [NEO ($1400)]. After 17 days, lettuce grown under NEO achieved higher (P ≤ 0.05) total biomass (939 g) than DES (812 g). There were no differences (P > 0.05) in the average individual plant weights in any treatment. Plant production efficiency (grams per square meter per kilowatt-hour) was higher in DES than NEO (P ≤ 0.05) but was not different from SPI and FLU (P > 0.05). Results indicate that low-cost LEDs are a viable option for producers looking to reduce investment costs while maintaining adequate plant growth. To further describe potential cost savings for producers, a partial budget analysis evaluated the net change in profits and benefit/cost ratio (BCR) of the experimental lights. All showed improved economic results compared with the control (NEO). These studies indicate that low-cost LED lights can support similar plant growth, at higher energy efficiencies, with better economic viability than more expensive grow lights.

Storage information regarding ‘Keepsake’ apple fruit is lacking. The objective of this research was to investigate the postharvest characteristics of ‘Keepsake’ apple (Malus ×domestica Borkh.), which is a parent of ‘Honeycrisp’. Apples were obtained from three orchards in Minnesota in 2022 and 2023, assessed for quality, and stored at 0 to 1 °C or 4 to 5 °C in air. Fruit were tested for firmness, soluble solids content (SSC), and titratable acidity (TA) for up to 6 months in storage. At harvest, fruit from different orchards differed in ground color, firmness, SSC, and titratable acidity. The starch pattern index did not differ among the orchards within a year, but it was greater during the 2023 harvest than during the 2022 harvest. Fruit firmness decreased less rapidly at 0 to 1 °C than at 4 to 5 °C. Changes in SSC with storage varied by orchard, storage temperature, and year. In 2022 to 2023, SSC changes were highly variable, remained the same during storage for fruit from one orchard, increased and then decreased for fruit from another orchard, increased after 1 month of storage, and then remained unchanged thereafter for fruit from the third orchard. In 2023 to 2024, SSC was generally unchanged during storage at 0 to 1 °C, and it increased slightly over time during storage at 4 to 5 °C. Titratable acidity decreased during storage, but there was no difference between storage temperatures. These findings demonstrate the difficulty determining when to harvest ‘Keepsake’ fruit because neither starch pattern index nor ground color is a reliable indicator of ripeness. Growers must rely on experience and fruit redness to determine when to harvest this late-season cultivar. To prolong fruit firmness, growers should store ‘Keepsake’ fruit at 0 to 1 °C rather than at 4 to 5 °C.

Continuous application of chemical fertilizers in plant cultivation can lead to the deterioration of the soil environment, resulting in reduced crop yield and quality. Currently, organic fertilizers, such as vermicompost, can partially replace chemical fertilizers and maximize yields while maintaining soil fertility. However, the effects of chemical fertilizers combined with vermicompost on watermelon (Citrullus lanatus) yield and quality are unclear. A field experiment was carried out on the watermelon cultivar Lihua No. 6. Six treatments were applied: no fertilizer (CK, control, 0N–0P–0K), 100% chemical fertilizer [CF, 5.4N–1P–5.4K (256, 47, and 255 kg·ha⁻¹)], 75% chemical fertilizer + 25% organic fertilizer [A1, 5.4N–1P–5.4K (192, 35, and 191 kg·ha⁻¹) + 2250 kg·ha⁻¹ vermicompost], 50% chemical fertilizer + 50% organic fertilizer [A2, 5.4N–1P–5.4K (128, 24, and 127 kg·ha⁻¹) + 4500 kg·ha⁻¹ vermicompost], 25% chemical fertilizer + 75% organic fertilizer [A3, 5.4N–1P–5.4K (64, 12, and 64 kg·ha⁻¹) + 6750 kg·ha⁻¹ vermicompost], and 100% organic fertilizer (A4, 9000 kg·ha⁻¹ vermicompost). Indices related to the growth, yield, and quality of watermelons were determined. Compared with CK, chemical fertilizer alone or in combination with organic fertilizers significantly increased growth parameters (plant height and leaf area) and chlorophyll content. The five fertilizer treatments enhanced the single fruit weight, yield, and biomass. In addition, the yield of reduced chemical fertilizer plus organic fertilizer was comparable to that of watermelons treated with CF. Compared with CF, the fertilizer treatments, especially the 1:1 mixture of chemical and organic fertilizer (A2) group, had elevated fruit-soluble solids and soluble sugar content, and reduced organic acid levels. Therefore, a combination of 50% chemical fertilizer and 50% organic fertilizer can effectively enhance the yield and quality of watermelons. These findings have important implications for guiding the management of watermelon fertilization and development of sustainable agriculture.

Limited preemergence herbicides are registered for new blackberry (Rubus subgenus Rubus) plantings. This greenhouse experiment was designed to investigate the effects of a broad selection of preemergence herbicides at multiple rates on blackberry transplants. Screening was initiated Aug 2021 and repeated Mar 2022 in Fayetteville, AR, USA, in a greenhouse at the Milo J. Shult Agricultural Research and Extension Center. ‘Ouachita’ blackberry plugs were transplanted into utility pots that contained field soil and growth media treated with preemergence herbicides. After transplanting, plant height was measured from the substrate to the highest apical meristem of 25 representative plants. Initial blackberry plant heights were 13.5 and 9.2 cm in 2021 and 2022, respectively. Twenty-five treatments were evaluated, consisting of 12 preemergence herbicides at 1× and 2× field rates, and one untreated control. Herbicide treatments included diuron, flumioxazin, halosulfuron, indaziflam, mesotrione, napropamide, oryzalin, pendimethalin, rimsulfuron, S-metolachlor, simazine, and sulfentrazone applied to substrate in containers at their respective 1× or 2× field rates. Data were collected on plant height, blackberry injury ratings, internode length, leaf chlorophyll content, and destructive harvest, including leaf count, leaf dry biomass, and aboveground dry biomass. Specific leaf areas and leaf area-to-dry matter ratios were calculated. When observed, plant injury tended to increase from 7 days after treatment (DAT) until 42 DAT. Greater injury levels were observed in response to treatment with mesotrione at the 1× (78%) and 2× rates (90%), halosulfuron at the 1× rate (58%), halosulfuron at the 2× rate (68%), and diuron at the 2× rate (73%). Injury from diuron was rate dependent, with the 1× rate causing relatively low injury (19%). At both the 1× and 2× rates, flumioxazin, indaziflam, napropamide, S-metolachlor, and pendimethalin treatments exhibited similar responses to the untreated control.