141 – Evaluation of Agriculture Chemicals, Biologicals and IPM Methods for Ornamentals
Principal Investigator: Dr. Cheryl Wilen, Integrated Pest Management Advisor, UC Cooperative Extension. For more project information, click here.
The University of California is relied upon to provide ornamental plant growers with unbiased evaluation of pest management and other projects. The objective of this project is to provide nursery growers, landscape, and turf pest management professionals, PCAs, and related industries with information on new or refined pest management methods with an emphasis on integrated pest management. Pesticides and other pest management methods or materials that have been newly developed or adapted will be evaulated for pest management in the targeted industries or end users.
The greenhouse and nursery facilities at the UC South Coast Research and Extension Center allows us to evaluate products for the IR-4 program in a controlled environment. This is adventageous because: 1) growers would not need to set aside a portion of of the growing area or worry that the test will inadvertently be moved or sold by workers, 2) the site is easily accessible to most growers in Southern California, and 3) products can be tested on a more regular basis.
187 - Biology and Management of Plant Parasitic Nematodes on Turfgrass
Principal Investigator: Dr. Becky Westerdahl, Department of Nematology, University of California – Davis. For more project information, click here.
Plant parasitic nematodes are microscopic roundworms that can be a major problem in turfgrass maintenance. The organophosphate nematicide Nemacur (fenamiphos) has been used in the management of nematodes on commercial turfgrass in California. Nemacur has been withdrawn from the market, and replacement management techniques are needed. There are currently no control measures available to California homeowners. A number of organic soil amendments and more conventional nematicides have been developed that have potential to reduce nematode damage to established turf. In addition, information on the biology and pathogenicity of nematodes on turfgrass is needed to develop environmentally sensitive programs for nematode management. Trials on the biology and management of plant parasitic nematodes on turf will be conducted on turfgrass plots that are currently available at SCREC.
154 – Selection of Lilacs with Low Winter Chill Requirements
Principal Investigator: Dr. Giles Waines, Department of Botany & Plant Sciences, University of California – Riverside. For more project information, click here.
The adaptation of 29 cultivars of lilac (Syringa) will be observed in a four-replicated field trial over three years to see if other cultivars than the three identified will prove adapted to coastal Orange County conditions. Of especial interest if whether Russian and Canadian germplasm will prove adapted, possibly on alternate years. A second objective is to observe whether death of old branches in summer is due to natural dieback, or due to possible susceptibility to Pierce's disease, which is a problem among lilac plantings at Riverside. Other pests and diseases will be monitored.
193 – Mineral Nutrition and Fertilizer Management for Landscape Palms
Principal Investigator: Dennis Pittenger, Department of Botany & Plant Sciences, University of California – Riverside. For more project information, click here.
Palms are commonly used in California’s urban and suburban landscapes and mature specimens are the emblematic signature landscape plant in coastal and Southern California. Several palm species commonly exhibit severe chlorosis and flecking on their leaves that greatly reduces their aesthetic value and appears to reduce their growth. It is likely that the responses are symptoms of nitrogen, magnesium, and/or potassium deficiency, but there is very limited reliable information on adequate tissue nutrient content or fertility management of palms grown in landscapes with a Mediterranean climate. This project will determine the Mg, K, and N requirement of landscape palms under California environmental conditions.
196 – Effect of Sand Backfill on Palms
Principal Investigator: Donald R. Hodel, Environmental Horticulture Advisor, UC Cooperative Extension. For more project information, click here.
Palms are important constituents of California’s landscape plant palette. Because of their unique root and trunk morphology, large specimens can be transplanted easily with a relatively small root ball. A common, standard industry practice is to use straight builder's or plaster sand as the sole back fill medium. There is no research-based information to support this expensive and time-consuming practice. This project will compare the use of builder's sand and the existing native site soil as the back fill media when transplanting queen palms (Syagrus romanzoffiana), one of the most common palms in the Southern California landscape.
The project will develop research-based recommendations regarding the use of builder's sand or native site soil as the back fill medium.
Ten specimens of queen palms will be dug and then replanted, using either builder's sand or native site soil as the back fill medium. The experimental design is a randomized complete block with two treatments (builder's sand and native site soil) and five, single-tree replications of each treatment. Palms will be rated for survival and leaf growth quarterly. Data will be subjected to ANOVA and other statistical tests as required.
206 – Biological Filtration of Greenhouse Irrigation Runoff
Principal Investigator: Dr. Loren Oki, Department of Plant Sciences, University of California – Davis. For more project information, click here.
This project examines biological filtration systems (BFS) that treat runoff water for reuse in the irrigation of greenhouse and nursery grown plants. A BFS system can remove pathogens and other contaminants from water yet is relatively inexpensive to install, simple to operate and easy to maintain. There are 4 objectives of this research project: 1) To optimize slow sand filtration by determining the maximum rate of filtration while still maintaining effective removal of plant pathogens; 2) to determine if a BFS system established against Phytophthora capsici can be effective in removing other Phytophthora species; 3) to determine the ability of BFS systems to remove nematodes from runoff water; and 4) to evaluate the use of existing BFS systems in California commercial settings.
207 – Autumn Sage Cultivars and New Selections
Principal Investigator: Dr. Giles Waines, Department of Botany & Plant Sciences, University of California – Riverside. For more project information, click here.
Autumn sages, Salvia greggii, S. microphylla, related species, hybrids (S. x jamensis), commercial cultivars, and new selections are valuable ornamental plants suited to water-wise gardening in Southern California. They bloom usually from spring into the fall, but mostly have a bloomless period in winter. This project will determine the start of flowering in spring and its cessation in fall at Riverside ARS and SCREC (Orange County) which have different temperature regimes typical of Southern California home gardens. With this knowledge it may be possible to breed and select cultivars that bloom year round. We will also determine the horticultural and ornamental performance of seed-grown plants with a tap root and laterals versus cutting produced plants with only adventitious roots. Entries will be ranked for bloom time, flower number, disease and pest resistance, and ornamental performance for home gardens and the nursery trade.
209 – UC Verde Foundation Block
Principal Investigator: Dr. Victor Gibeault, Emeritus Cooperative Extension Environmental Horticulturist, University of California – Riverside. For more project information, click here.
This project is for the maintenance of the mother block of ‘UC Verde’, a UC patented buffalograss. The site is available to the public to demonstrate low-water requiring landscape plant material in a block of sufficient size to clearly show the plant characteristics. At the same time, it is important to retain a secure and protected mother block of the grass to minimize the chance of any contamination. Interest in this warm season grass stems from the low-water use characteristics; the unique dormancy / drought avoidance ability of turfgrass to survive summers with no supplemental water, if needed, when irrigated again in late summer; and the pleasing aesthetic appearance of the turfgrass under varying mowing heights and when used as a “no-mow” ornamental ground cover. The recent drought years in California, and the Southwest, and a future of more expensive water and / or possible water restrictions for urban and suburban landscapes have highlighted the need for a resource efficient turfgrass, such as ‘UC Verde’.
222 - Evaluation of Propiconazole for Control of Fusarium Wilt of Canary Island Date Palm
Principal Investigator: Donald R. Hodel, Environmental Horticulture Advisor, UC Cooperative Extension. For more project information, click here.
Fusarium wilt of the iconic Canary Island date palm (Phoenix canariensis), a popular landscape tree, is a lethal and increasingly common disease in California and elsewhere. This disease is particularly troublesome because documented treatments are unknown and replacement Canary Island date palms replanted in the same location where one died from Fusarium wilt invariably become infected. This study evaluates the effectiveness of the fungicide Propiconazole, when injected directly into leaf bases near the apical meristem, to control Fusarium wilt.
232 - Landscape Plant Performance: Water Use Assessments and New Cultivar Selections
Principal Investigator: Dr. Loren Oki, CE Specialist, Environmental Horticulture, Co-Director, UC Nursery & Floriculture Alliance Department of Plant Sciences, University of California, Davis
Co-Investigators: Dr. Darren Haver, Water Resources Advisor, University of California Cooperative Extension Orange; Karrie Reid, Environmental Horticulture Advisor, University of California Cooperative Extension San Joaquin; Dr. Ryan Contreras, Associate Professor, Department of Horticulture, Oregon State University
This project will determine irrigation requirements and assess disease resistance of new and recently introduced landscape plants at South Coast Research and Extension Center. Plants will be established in year one and exposed to irrigation treatments in year two. Plants will be measured for growth, assessed for disease resistance, and evaluated for aesthetic quality. Three new fields will be installed at the University of California, South Coast Research and Extension Center in Irvine, CA to duplicate the University of California, Davis fields. This project will collaborate with the plant breeder, Dr. Ryan Contreras, Oregon State University Department of Horticulture, to bring his landscape plants to California. The test site design will enable the concurrent determination of the fire blight resistance and irrigation requirements of Dr. Contreras' Cotoneaster plant selections.
233 - Identifying Growth Reduction Rates for Shrubs Using Shortstop 2CS
Principal Investigator: Don Hodel, Environmental Horticulture Advisor, University of California Cooperative Extension Los Angeles.
Growth in landscape shrubs pose a challenge to landscape managers from both a green waste and labor standpoint. Plant growth regulators (PGR) have had some benefit as foliar sprays but must be repeated throughout the season to be effective. Shortstop 2SC (22.3% wt. /wt. Paclobutrazol, Greenleaf Chemical, LLC.) is one of several PGR options but has a longer residual than other products when applied as a soil drench. This trial will assess several Shortstop 2SC rates with some commonly planted shrubs for growth reduction over a 2-3 season period.
234 - Pollinator Project
Principal Investigator: Dr. Jim Bethke, Emeritus Nursery and Floriculture Advisor, University of California Cooperative Extension San Diego.
The ornamental horticulture industry supplies diverse plant resources necessary for pollinators. However, to maintain plant quantity and quality, and to allow shipment of plants across state and national borders, crop production and landscape maintenance often requires the use of pesticides to manage insect pests. The use of systemic insecticides could lead to unintended exposure and risk to pollinators through ingestion of nectar and pollen, but there are significant gaps in understanding the level of exposure of pollinators to treated plants. The objective of the present study is to analyze the residue of different neonicotinoids on the pollen and nectar of common ornamental plants. Our results will be combined with similar data from all over the United States to cover all climates and growing zones, then published for growers, landscape professionals, and the general public who can contribute to pollinator health and conservation.
239 - Advancing Urban Irrigation Management to Enhance Water Use Efficiency
Principal Investigator: Dr. Amir Haghverdi, Assistant CE Specialist, Department of Environmental Sciences, University of California, Riverside
Co-Principal Investigator: Dr. Darren Haver, Water Resources Advisor, University of California Cooperative Extension Orange.
The US west is generally arid and subject to droughts, yet some of the largest cities across the nation are in this region. Irrigation demand is usually the largest component of total outdoor water use in urban sectors. Therefore, improving irrigation water use efficiency of urban landscapes is crucial for maintaining urban green infrastructure. This project will develop and disseminate scientific knowledge, and practical recommendations for sustainable urban irrigation management through field research trial, and laboratory analyses. A three-year turf irrigation research trial will be conducted at SCREC to develop turfgrass irrigation best management practices (BMPs) to sustain the desired landscape quality using minimum water. On a technological level, smart irrigation technologies will be used to develop water conservation strategies. The findings of this project will be published in peer reviewed journal articles and presented at scientific conferences and disseminated through a variety of extension approaches including field days, on-farm demonstrations, workshops, meetings, and extension publications.