HRI Moves to Combat New Phytophthora Strain
In response to the recent discovery of Phytophthora austrocedri, the Horticulture Research Institute (HRI) has announced nearly $250,000 in funds have been made available to target urgent research needs for the nursery industry. These funds are provided through the USDA Agricultural Research Service (ARS) Floriculture & Nursery Research Initiative (FNRI) and will be used to study management strategies for this emerging threat.
Phytophthora austrocedri is a water mold that causes severe disease response in woody plants, affecting the roots and collar area, and leading to decline and eventual death of infected plants. First detected in Argentine Patagonia, where it was linked to widespread dieback of native
Austrocedrus chilensis trees, the pathogen has been
detected in two Oregon nurseries.
The pathogen’s ability to survive in soil and move through irrigation water makes control difficult. Currently, plants most at risk are in the Cupressaceae family, including popular nursery species such as Leyland cypress and Chinese juniper. Without this rapid response from AmericanHort and HRI, this dangerous pathogen can have severe economic consequences for the nursery industry. Moreover, this pathogen poses risks for natural ecosystems where native species may eventually be impacted—a problem we absolutely do not want.
Phytophthora austrocedri killing juniper. (Photo used with the permission of Forestry Research. Crown Copyright, Forestry Research, United Kingdom.)
The funding will support the development of best practices to combat this pathogen on farms and limit the dispersal, exploring chemical controls that can effectively manage the pathogen in both nursery and landscape settings. Biological controls will also be explored, leaving no rock unturned in this quest to support the ornamental industry. The research team includes Drs. Nik Grunwald, Jared LeBoldus, Sara Navarro, Mana Ohkura, Alan Peper, Ebba Peterson and Jerry Weiland, all of which are poised to prevent further spread of the pathogen.
Plants infected with P. austrocedri typically exhibit symptoms such as root and collar rot, which can lead to the gradual decline and death of the plant. Early signs include yellowing or browning of foliage, often starting at the top of the tree. As the disease progresses, the bark at the base of the trunk may crack, revealing necrotic, discolored tissue underneath. In advanced stages, the tree may show dieback from the crown, and infected roots become blackened and decayed, ultimately leading to plant death. These are similar to other Phytophthora species, so laboratory testing is needed to confirm the species. If you feel you may have this issue, please contact your local extension office to confirm.
Lesion at the stem base. (Photo used with the permission of Forestry Research. Crown Copyright, Forestry Research, United Kingdom.)
HRI’s ability to prioritize research and collaboration with industry experts underscores the commitment to providing the industry with practical solutions to safeguard plants, landscapes and the green industry from emerging threats.
Long-term Sustainability of Peat in Horticulture
Peat moss is one of the most critical resources for the horticulture industry and proper management practices will ensure this resource stays viable for the future.
The American Society for Horticulture Science is hosting a free webinar on Tuesday, October 8 (TOMORROW) at 2:00 p.m. Eastern/1:00 p.m. Central overviewing the sustainability of peat moss. In this webinar, Dr. James Altland, Research Leader with the Application Technology Research Unit at the USDA-ARS in Wooster, Ohio, will be discussing some of the issues surrounding peat use in horticulture and some options for growers.
For the past few years, there's been no bigger topic in substrates than peat and this webinar should be an insightful look into the North American peat harvesting and production practices, as well as shed light on some of the differences between North American and European peat production.
Peat is harvested by scraping the upper layers off the bogs.
You can register
HERE to watch this free webinar.
New Educational Tool for Preemergence Herbicide Application
Ever had a question about your preemergent application procedures or wonder if you could be deploying herbicides more efficiently? Envu is developing tools to support growers with easy-to-use guides to answer these questions and more.
Recently, they released “Herbicide Calibration,” an educational video that demonstrates best practices for calibration and application of herbicides for nursery growers. This video guide is a resource for the industry to use to learn the precision application of preemergence herbicides in order to deliver long-lasting, intended benefits of broad-spectrum control. The information in this video can help reduce labor demands and potential re-treatment costs.
Like any pest management tool, preemergence herbicides need to be utilized properly to deliver the intended benefits. To maximize performance from preemergence, the application must be uniform and done at the correct rate. This video and other resources from Envu can help ensure that these requirements are met.
In addition, personal protective equipment (PPE) requirements are covered. You can watch the video
HERE.
“We are hopeful the video, along with the Envu product portfolio, will be a useful tool for growers as they work to grow beauty from the ground up,” said Janna Beckerman, Green Solutions Team Specialist at Envu.
Monrovia Announces Distinctive Selections for 2025
Each year, Monrovia puts out an updated list of their Distinctive Selections, which follows consumer insights to ensure that landscapers can fit the perfect plants to current design and landscape trends. Not only do they put out a list, they publish an INFORMATIVE GUIDE that has information to help with selections and use in the gardens. The guide covers everything from annuals, perennials and shrubs to more specific plan uses, like edibles, pollinators and water-wise plants.
Along with the guide, Monrovia publishes a webinar on garden trends for 2025 that you can find HERE. With this information in hand, you should easily be able to set up world-class landscapes for your customers and impress their neighbors—or possibly make them jealous!
Two Greenhouse Online Courses Starting in October
The University of Florida Greenhouse Online Training has two courses starting in October that can help you improve your skills and the knowledge level of your employees.
"Weed Management" is a critical application for all growers, regardless of skill level and production type. However, the more you know, the more efficient you can be with your practices. If you want to take the jump to the next level, join Dr. Chris Marble, an associate professor of ornamental and landscape weed management at the University of Florida, for this four-week course. Dr. Marble will focus on teaching the importance of identification and proper application. His courses are incredibly easy to follow and learn. As a bonus, this course is offered in both English and Spanish.
"Success With Your Latino Workforce" is another course starting in just a couple weeks. Taught by Claudio Pasian, Professor Emeritus at Ohio State University, this brand new course will prepare you to work with Latino employees to solve issues in the workplace, particularly those that are the consequence of a mixed culture workforce. Common Spanish terms and phrases will also be covered. This course is only offered in English.
The courses cost $275 and run about four weeks. You can register
HERE. All materials will be conducted online and available on demand.
MANTS Early Bird Registration Open
The Mid-Atlantic Nursery Trade Show (MANTS) is scheduled for January 8 – 10 at the Baltimore Convention Center. This premier event for the horticultural industry attracts over 11,000 attendees and 900 exhibitors each year. Not only that, but 82%of attendees indicated that they were decision-makers or influencers within their organizations. That means, if you want to make business connections and decisions, this is the show to attend.
Currently, MANTS is in Early Bird Registration, which means you can lock in the best price for attendance and make sure you reserve your spot. Right now, it's only $20 per person to join for all three days, so why wait? MANTS is known as the “Masterpiece of Trade Shows” and is proudly sponsored by the state Nursery & Landscape Associations of Maryland, Virginia and West Virginia. Due to its central location, this is a perfect destination for horticultural leaders.
You can also get discounted hotel reservations available within walking distance to the convention center. To register, visit
MANTS.com.
Think big,
Jeb Fields
Editor-at-Large
Nursery & Landscape Insider
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