This article shares survey results provided by both consumers and growers regarding the University of Florida Biodiversity Certified Plants for the Rapidly Expanding Urban Landscape Market project conducted at the University of Florida (UF). The overall goal of this project was to develop and test a scientifically based, UF-trademarked process for the certification of high-quality, commercially available, wildlife-friendly plants for the green industry. The objectives of two surveys that targeted consumers and growers, respectively, were to assess consumer and grower attitudes, knowledge, and behaviors pertaining to wildlife-friendly plants and a proposed certification. The consumer survey results (n = 868) indicated that respondents (consumers) strongly agreed with purchasing wildlife-friendly plants, and that respondents would benefit from the proposed certification. The certification could help consumers gain a better understanding of which plants are wildlife-friendly at the point of purchase. Nearly half of consumers reported an inability to identify wildlife-friendly plants in the store, which hinders them from purchasing. The grower survey results (n = 75) indicated that respondents were willing to offer biodiversity-certified plants. More growers rated themselves as innovators (the most innovative category) in terms of adopting innovations than any other diffusion of innovations category (early adopter, early majority, later majority, hesitant, or none of these), although the perceived cost of obtaining the certification was seen as a potential barrier toward grower adoption of the certification. These findings indicate that the proposed certification would be successful with appropriate and tailored marketing materials for both growers and consumers.
The use of polyethylene (PE) mulch causes environmental pollution where incomplete removal leaves fragments susceptible to escape to ecosystems, such as the ocean, where they can cause ecological harm. PE mulch is generally nonrecyclable due to contamination with soil and crop debris after use, leaving growers with few end-of-life options for used PE mulch. Research studies have shown that soil-biodegradable plastic mulch (BDM) is comparable to PE mulch in terms of performance, soil health, and overall economics and is preferred from an environmental perspective, but the adoption of BDM by producers is still low. Previous research has shown that the primary barriers to BDM adoption are insufficient knowledge about BDM, high purchase cost, and unpredictable breakdown of BDM in the soil. The high purchase cost of BDM compared with PE mulch is offset by the costs for PE mulch removal, transport, and disposal fees. This project was conducted to develop BDM training materials, to educate and assess BDM knowledge gained by extension personnel and other agricultural professionals through trainings and webinars, and to educate producers about BDM through hands-on experience. Thirty-six research and extension publication outputs from two previous US Department of Agriculture Specialty Crop Research Initiative BDM projects were reviewed and transcribed into 45 new extension publications that included 11 slide presentations, 5 lecture slides, 10 fact sheets, and 3 videos. All the training materials are posted on a public university website. Professional development trainings were conducted at local, regional, national, and international levels to provide agricultural professionals the current, science-based information on BDM and resources for information. Survey results showed that at a local level, the greatest change of knowledge among participants was observed for “BDM use in organic production” (60%), and the lowest reported change of knowledge was observed for “limitations to PE mulch disposal” (19%). At a regional level, out of 58 participants, 23% to 35% of participants learned “a lot” and 35% to 51% learned “some new information” regarding BDM from the webinar. At the national level, out of 30 participants, 48% responded that they learned “a lot” and another 48% learned “some new information” on BDM from the training. Growers were trained about BDM via field days and on-farm demonstrations where five strawberry (Fragaria ×ananassa) growers volunteered to participate in BDM trials. The participant growers observed no difference in weed control and fruit yield between the PE mulch and the BDM. Growers expressed concerns about slow biodegradation of BDM after soil incorporation, potential impacts on soil biological activity, food safety concerns with BDM fragments and that BDM is not currently permitted for use in organic production.
Increased urban and suburban populations in the arid western United States have resulted in more water demand; however, water availability in the region has become limited because of inadequate precipitation. Recent droughts have led to restrictions on irrigating landscape plants. Garden rose (Rosa ×hybrida) is commonly used as flowering plants in residential landscapes, but its drought tolerance has not been widely studied. The objective of this study was to determine the impact of reduced irrigation frequency on visual quality, plant growth, and physiology of five garden rose cultivars, including ChewPatout (Oso Easy® Urban Legend®), Meibenbino (Petite Knock Out®), MEIRIFTDAY (Oso Easy® Double Pink), Overedclimb (Cherry Frost™), and Radbeauty (Sitting Pretty™). Twenty-four plants of each rose cultivar were established in a trial plot at Utah Agricultural Experiment Station Greenville Research Farm (North Logan, UT, USA) in Summer 2021. Plants were randomly assigned to one of three deficit irrigation treatments for which irrigation frequencies were calculated using 80% reference evapotranspiration (ETO) (high), 50% ETO (medium), and 20% ETO (low). The total volumes of irrigation water applied to each plant were 345.6, 172.8, and 43.2 L for the high, medium, and low irrigation frequencies, respectively, during the deficit irrigation trial from 12 May to 30 Sep 2022. Root zones were wetted more frequently as irrigation frequency increased from low to high irrigation frequencies. Decreased irrigation frequency increased the number of visibly wilted and damaged leaves on all rose cultivars. However, only ‘Meibenbino’ and ‘MEIRIFTDAY’ exhibited a reduction in overall appearance under decreased irrigation frequency. The relative growth indices of both ‘Meibenbino’ and ‘MEIRIFTDAY’ decreased by 6%, whereas the dry weights of their leaves decreased by 37% and 36%, respectively, as irrigation decreased from high to low frequencies. Roses in this study appeared to decrease stomatal conductance up to 51% when irrigation decreased from high to low frequencies, or when air temperature increased. ‘Meibenbino’ and ‘MEIRIFTDAY’ exhibited unacceptable overall appearance, growth reduction, and higher leaf–air temperature differences, and they were less tolerant to reduced irrigation. Although the ‘Radbeauty’ maintained plant growth under the reduced irrigation frequency, the large leaf size led to a more visibly wilted appearance and the potential for heat stress, thus impairing visual quality. ‘ChewPatout’ and ‘Overedclimb’ were most tolerant to deficit irrigation at 20% ETO and maintained plant growth with acceptable visual quality and lower leaf temperatures when they received one irrigation during the growing season.
Dahlias (Dahlia ×hybrida) are a popular cut flower for local production in the northeastern United States. However, there are more than 20,000 cultivars to choose from, and the suitability of these cultivars as cut flowers varies regionally. Fourteen dahlia cultivars were grown in Orono, ME, USA: Blizzard, Burlesca, Café au Lait, Café au Lait Rose, Clearview Daniel, Cornel, Cornel Bronze, Ivanetti, Lollipop, Neon Splendor, Rock Run Ashley, Sunspot, Tanjoh, and Tempest. These cultivars were selected after interviews with local dahlia growers. These cultivars all produced similar numbers of flowers, but they differed in the time to form flowers, stem length, and stem diameter. ‘Rock Run Ashley’ was the earliest to begin flowering, at 35 days earlier than ‘Tempest’ and ‘Café au Lait’, which flowered last. ‘Blizzard’ and ‘Tempest’ had the longest stems and ‘Lollipop’ had the shortest stems. Growers may want to choose ‘Rock Run Ashley’ if they need flowers earlier in the season, or ‘Blizzard’ or ‘Tempest’ if a longer stem length is desired. During a second study, we harvested field-grown flowers of ‘Burlesca’, ‘Cornel’, and ‘Ivanetti’ and treated them with deionized water or one of two commercial holding solutions. Holding solutions did not extend the vase life of ‘Burlesca’ or ‘Ivanetti’, but they increased the vase life of ‘Cornel’ by 4 or 5 days.
Cercospora leaf spot (CLS), caused by the fungal pathogen Cercospora beticola, is the most destructive foliar disease of table beet (Beta vulgaris ssp. vulgaris) in Wisconsin, USA, and globally. Under conducive conditions, symptomatic lesions on the leaf expand and coalesce forming large necrotic areas that can ultimately lead to complete defoliation. This damage reduces productivity and threatens the ability to mechanically harvest. CLS damage also detracts from the visual appeal of fresh market bunched beets to such an extent that growers risk buyer rejection if CLS severity is observed to be greater than 5%. Fungicide use for CLS control is threatened by the emergence of resistant C. beticola strains, and the application of host resistance is constrained by limited knowledge of cultivar reaction to CLS in table beet. This study aimed to address the knowledge gaps of fungicide efficacy and cultivar reaction by conducting replicated field trials in multiple table beet growing environments across Wisconsin. Broad variation for resistance to CLS was observed among the 10 included cultivars. The mean area under disease progress curve (AUDPC) across environments for the most susceptible cultivar was 267% greater than the most resistant cultivar. Spearman correlations between environments for mean cultivar AUDPC value ranged from 0.71 to 0.99, revealing consistent cultivar CLS reactions across environments. Although susceptible cultivars surpassed 5% severity in all environments, the resistant cultivars remained below this threshold in six of the 10 environments. By comparison with resistant sugar beet (Beta vulgaris ssp. vulgaris) cultivars, however, all tested table beets appeared susceptible to CLS, highlighting the potential for a CLS breeding effort in table beet. Neither of the evaluated Organic Materials Review Institute–listed treatments were effective at limiting CLS disease progress, whereas both tested conventional fungicides significantly reduced disease severity over the nontreated plots. These findings may provide helpful guidance to table beet growers affected by CLS in Wisconsin and beyond.
Mulching landscape beds is a common task for landscapers seeking to affect soil conditions and reduce weed pressure. This study investigated the effects of three pine (Pinus sp.) straw mulch depths (5, 10, and 15 cm) on soil moisture/temperature modulation during late winter/spring. No differences in soil volumetric water content were observed; however, increasing mulch depth to ≥10 cm decreased fluctuations in temperature. This research provides a better understanding of the effect of mulch depth and potential environmental benefits so that landscape contractors can determine cost-benefits of mulching applications.
The newly released “Plant This Not That: A Guide to Avoiding Invasive Plant Species in Florida” booklet emerges as a crucial tool in cultivating a comprehensive understanding of invasive species, facilitating informed decision-making in plant selection. Its unique focus on illustrating alternatives to invasive plants, coupled with its accessible format, can empower individuals to contribute to the preservation of Florida, USA, ecosystems. The booklet’s impact was displayed through an in-service training for 58 University of Florida/Institute of Food and Agricultural Sciences extension personnel. Following the in-service training, attendees demonstrated statistically significant improvements in their perceived knowledge of four key invasive species concepts. This study highlights the booklet and accompanying training’s potential as a valuable resource for mitigating the impacts of invasive plant species.
Propiconazole has fungistatic and fungicidal properties against Harringtonia lauricola, the causal agent of laurel wilt disease. Propiconazole injections are used by Florida, USA, farmers as a prophylactic method to manage the disease in avocado (Persea americana) trees, but its efficacy has remained questionable for more than a decade due to documented restricted mobility within the tree vascular system. This study was conducted to evaluate the absorption of propiconazole when using soil drenching as an alternative application method, assess the efficacy of propiconazole in controlling disease development when drenched or injected, and its synergistic effect on common cultural management practices used by the local farmers, such as branch removal and trunk cutting (“stumping”). To determine if propiconazole soil-drenching can provide better xylem coverage, potted and mature orchard trees were treated with different concentrations and artificially inoculated with the pathogen. Propiconazole translocation from the roots to above-the-ground tissue was confirmed in potted and orchard trees, but the concentrations in orchard trees were below the fungicidal threshold (1 ppm). Although none of the potted trees developed laurel wilt symptoms, all inoculated branches of the orchard trees did. Furthermore, noninoculated branches in more than 80% of the inoculated and propiconazole-treated orchard trees developed symptoms, even though the inoculated branch was cut at the early stages of disease development. To elucidate if propiconazole injections effectively control the disease, trees from a commercial orchard that were injected five times were challenged by artificial inoculation. Propiconazole concentration in trees was highly variable (ranging from < 0.01 to 294 ppm), but even in trees with a high concentration of propiconazole, inoculated and noninoculated branches developed symptoms. Even though drenched and injected trees were “stumped” soon after symptoms appeared in the noninoculated branches (4 to 5 months after inoculation), all of the stumps in the drenched plot and 80% of the injected trees, showed internal symptoms 5 and 4 months after the cut, respectively. Results demonstrate that the soil-drenching of propiconazole is an ineffective application method in orchard trees, and that the conventional injection does not prevent disease development after artificial inoculation. Moreover, because propiconazole does not prevent the movement of the pathogen to the trunk, the “stumping” of infected trees to reduce the disease in the orchard is an inadequate practice. This study highlights the critical need for other active ingredients with lower fungicidal thresholds, longer half-life, and higher xylem mobility.
Horticulturists and agronomists have a long history of using selective breeding to take advantage of intraspecific (within-species) variation with the goal of developing novel varieties of plant species. These efforts are responsible for the availability of countless improved food, forage, and ornamental varieties that are valued by farmers, landscapers, and home gardeners. In contrast, little attention has been paid to the idea of evaluating intraspecific variation to identify plants derived from a specific ecosystem (ecotypes) of native species that could improve the success rate of habitat restoration and enhancement projects, especially in aquatic systems. These projects often specify that plant material used for restoration be collected from local donor sites to preserve the area’s gene pool, but nearby source populations may be nonexistent or may not be well-adapted to conditions at the recipient (transplant) site. This paper, which summarizes information presented at the American Society for Horticultural Science Invasive Plants Research Professional Interest Group workshop in 2022, provides evidence that unimproved, wild-type species can be useful in aquatic habitat restoration and enhancement projects, particularly when conditions at sites targeted for restoration differ from those in nearby systems, or when sites are expected to undergo shifts in conditions because of factors such as climate change.
The objective of this greenhouse study was to evaluate tall fescue (Festuca arundinacea) seedling growth when seeded after herbicide application. Herbicide treatments included a nontreated control; 1.19 lb/acre 2,4-dichlorophenoxyacetic acid (2,4-D) + 0.32 lb/acre methylchlorophenoxypropionic acid (MCPP) + 0.32 lb/acre dicamba; 0.75 lb/acre quinclorac; and 0.06 lb/acre halosulfuron-methyl. Seeding was done at 0, 3, 7, or 14 days after herbicide application to soil media. Two identical experiments were conducted in the greenhouse: Expt. 1 seedling growth from January to March and Expt. 2 from May to July (temperatures higher). Seeding dates after herbicide application did not influence growth. Average dry shoot weight reductions and dry root weight reductions caused by postemergence herbicides were 2,4-D + MCPP + dicamba (33% shoot and 27% root in Expt. 2), quinclorac (30% shoot and 37% root in Expt. 2), and halosulfuron-methyl (51% shoot in Expt. 2; 81% root in Expts. 1 and 2). Although application of these herbicides before seeding in the field may result in no visual impact, they can impact seedling shoot and root growth, particularly under higher growth temperatures.