New Light Shed on Bee Parasites, Pathogens

With all the discussion about honey bee health, the implication is that a wealth of information exists about what is normal or healthy for a honey bee. Sadly, there is not. Very little information exists detailing the presence of honey bee pests in the US. Finally we are getting some answers.

The National Honey Bee Disease Survey was initiated in 2009 to document honey bee pests and pathogens throughout the US in the response to concerns over declining honey bee populations and to meet import/export requirements for international trade. A report summarizing the first five years of sample collection has just been published. Researchers detailed their observations on mites, fungal pathogens, and viruses. A critical component of the survey is to also analyze pesticide residues in apiaries; however, this information was not included in this report.

During the first five years of the survey, populations of Varroa mite and Nosema spp. (a fungal pathogen of honey bees) were far greater than expected. From 2009-2014, Varroa mites were positively identified in 87 – 98% of the sampled apiaries, and their populations were surprisingly seasonal. The highest monthly Varroa mite loads were observed in August through November. Furthermore, 55-70% of all sampled apiaries had mite populations over the critical economic threshold level at the critical time right before winter. Nosema spp. incidence ranged from 42-79% of sampled apiaries during 2009-2014, and was greater in migratory colonies (than stationary colonies).

Varroa mites are closely linked to virus infections; so, it follows that researchers saw a high incidence of viral infections associated with high mite populations. Eight viruses were monitored each year. Dwarf wing virus consistently had the greatest incidence with detected levels above 80% each year, while chronic bee paralysis virus doubled annually since 2010.

There is some good news: three exotic pest problems of, Tropilaelaps mite, slow paralysis virus, and Apis cerana (Asian honey bee), have not yet been detected in the US.

Researchers at the University of Maryland and USDA lead this multiyear effort. This first summary will serve as a baseline to measure trends and patterns over time, bringing much needed information to identify drivers of poor bee health. Plus it will be useful for detection of changes and new pests. Researchers also plan to correlate colony health to in-hive pesticide residues.

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Soilless Substrate Science - Ushering in the Next Generation of Growing Media

By Jennifer Gray • May 28, 2026

Soilless Substrate Science (S3) is a national transdisciplinary collaboration developed to support growers as we advance to the next generation of substrates. Our team is leading North American efforts to develop new substrate materials and techniques, and working with growers to support implementation, as we support the global transition to substrates that go Beyond Peat. In this webinar, Dr. Jeb Fields will discuss the S3 team efforts surrounding identification of new substrate materials, processing and development, and grower support. We will explore wood fiber processing, sugarcane bagasse substrate development, stabilization of organic fibers, databasing substrate materials, and opportunities for growers to get involved. Overall, attendees will learn about US efforts to develop domestically-sourced substrates and advance substrate science as we move towards the next generation of substrate science. Our Speaker Dr. Jeb Fields is a production horticulturist who works with growers in Florida and throughout the country to support more effective and efficient production practices through his environmental nursery research program. Jeb’s primary interests include growing media & substrate science, irrigation & fertilizer management, whole plant-water relations and plant abiotic stress physiology. Jeb is an internationally recognized substrate scientist, the leader of the Beyond Peat project through the USDA Specialty Crops Research Initiative, and the national S3 (Soilless Substrate Science) team which pursues advancements of the global substrate industry and development sustainable substrate materials and practices, including substrate stratification. Jeb is the editor for Nursery & Landscape Insider, a biweekly e-newsletter from Ball Publishing, that reaches over 32,000 stakeholders worldwide. For his efforts, he has been recognized with numerous awards, honors, and leadership positions. Prior to joining UF, Jeb was a professor and research station director with the LSU AgCenter. Jeb studied at UF for his B.S., NC State University for his M.S., and Virginia Tech for his Ph.D. – with all degrees focusing on production horticulture.

A soft-focus background of varying shades of green, suggesting grass, foliage, or a forest landscape.

Understanding Why Rose Rosetting Disease Appears in Distinct Regions of a Shrub Rose Plan

By Jennifer Gray • April 9, 2026

This webinar dives into the problem of rose rosette virus. Shrub roses consist of multiple canes attached to a root system and produce beautiful spring growth in the form of new flowering stems and branches. Experts will provide an overview of how rose rosette virus first attacks flowering growth and can move throughout the stem. At the same time rosette symptoms appear in mature distinct stems of a plant and may be absent from others. The research delves into understanding how the vascular system connects the flowering stems and above ground canes. The research is to understand how virus movement between adjacent stems and only appears to cause disease in a few but not all canes of the same plant. This research is important to explore potential management approaches to safeguard rose.

From Propagation to Consumers: HRI Research Powers Every Link in the Green Industry Supply Chain

By Jennifer Gray • March 24, 2026

The horticulture industry continues to change as new technologies, production practices, and consumer expectations reshape the marketplace. Research plays an essential role in helping growers, landscapers, and retailers adapt and succeed. That’s exactly where the Horticultural Research Institute (HRI) enters the chat. Every year, HRI selects and funds research projects that advance horticulture. In 2026, HRI is investing more than $560,000 in 18 research projects that target challenges across the horticultural supply chain, including plant production, pest and disease management, landscape plant performance, and consumer insights. “What makes HRI research so valuable is that it focuses on real challenges the industry is facing right now,” said Mark Yelanich, HRI President and Research Director at Metrolina Greenhouses. “The 2026 HRI-funded projects were selected because they develop knowledge, processes, or tools that businesses can actually use.” HRI’s four strategic research priorities guide funding decisions, focusing on quantifying plant benefits, creating innovative solutions, gathering consumer insights, and producing practical solutions to industry challenges. The 2026 projects reflect these priorities across the horticulture supply chain.