Boxwood Blight Update
We hope everyone is having a great winter, but more importantly, we hope everyone is ready for spring to start very soon. We are back in full swing this week potting perennials, annuals, and roses, pruning fruit trees, loading a few trucks, and much more.
Over the past 6‐8 months, I have spent hours talking to people who have discovered boxwood blight in their landscape or others who are working tirelessly in research to conquer it. Great information is coming in from both sides to help us better understand and defeat the disease. Recently, there was an article published showing boxwood blight at President Woodrow Wilson’s home in Staunton, VA. That discovery, along with other incidences of boxwood blight in central Virginia and beyond, has triggered us to prepare a new update on what is going on with the disease. This update focuses on new protocol Saunders Brothers is taking as well as some of my thoughts on the disease. We feel that it is only a matter of time until see it, as it seems to be closing in around us. But our hope is that time is later rather than sooner.
At Saunders Brothers we have enacted a few further steps to not only lessen the chance of the disease entering the nursery but also ways to contain and minimize the spread of it when it is discovered.
Some New Saunders Protocol:
• We will be sending dig orders to the field twice a week (instead of 5x), Tuesday at noon and Friday at noon.These orders will be available for delivery one week later. Please anticipate these deadlines when placing your orders. Limiting our digs to twice a week will lessen the times we enter each field and limit the chance wespread boxwood blight. We will also be taking steps to clean equipment and employees between fields.
• We will pull all container boxwood orders once daily thus minimizing the times we enter boxwood production houses. So please remember once a delivery is confirmed you will not be able to change your order after that point as the boxwood will have been pulled by truck load batch. Once they arrive at the shipping dock they can no longer be returned to a production house.
• To pick up a boxwood order at the nursery, you must schedule your pickup appointment no later than noon one day prior to pick up. Non‐boxwood pick up orders should be placed a minimum of 6 business hours in advance of pickup time.
• We continue to only trial the boxwood genetics that we had on the farm prior to 2011 when the disease was discovered in the US. Thankfully, we had over 100 varieties in house at that time. Many of you have offered new promising plants for us to trial and we hope to have protocol in place soon to allow us to do that.
• We will continue to not allow any farm equipment or tools to be used in any off property landscape. We are aware of several instances where plants have been infected by ‘dirty’ tools that have been used in one location and picked up the disease and moved it to a ‘clean’ landscape.
• We have installed gates at all entrances to our production areas. Several years ago, we eliminated anyone getting out of a vehicle in the nursery, but this year decided to even further limit any possible traffic during and after hours. As you know, rules are only for those who follow them. Closed gates stop curious people.
• We are issuing company approved rubber boots to employees who enter boxwood production areas that they will be required to clean as they leave the area. This will limit the movement of the disease if it is present.
We continue to believe that the answer to boxwood blight is going to be with resistant varieties. Multiple tests are proving this over and over. We feel there must be a gradual evolution to the resistant cultivars. In addition, we will begin introducing some new varieties in the next several years that are showing great results in boxwood blight trials as well as our boxwood leaf miner trials. We own our first patent and have applied for a second one and hopefully more to come.
A few general rules of thumb on varietal resistance are:
• Sempervirens cultivars are more susceptible.
o English, American, Vardar Valley, Jensen, Justin Brouwers (not officially semp but almost)
• Microphylla, Insularis, Harlandii, Koreans are most resistant.
o Green Beauty, Jim Stauffer, Insularis Nana, Franklin’s Gem, Richard, harlandi, John Baldwin,
Wintergreen, Winter Gem
• Green’s (Velvet, Mountain, Mound, Gem) are in the middle.
• Architecture of plant and environment are playing major roles.
o Taller more open sempervirens do well (Dee Runk, Fastigiata)
o Very tightly sheared microphyllas grown close to the ground become more susceptible
o Susceptible plants in areas of good air flow are doing fine
A few other general comments:
Ultimately we as nurserymen, gardeners, landscapers, and plant enthusiasts must be smarter about what we do.
• Follow the Best Management Practices that most states have published with regard to boxwood blight.
•Use the diagnostic labs if problems are suspected. It made me cringe when I heard about a landscape thatfought the disease for over a year before it was tested and positively ID’ed. How many landscapes were infected in the meantime as a result?
•Be smart if it is ID’ed. Stop traffic in the area. Don’t try to clean it up until you research how. I heard of one instance where a leaf blower was used to clean up a diseased area. It was successful at removing dead foliage but I won’t mention where that foliage landed.
•We must do a better job taking care to not move the disease on us or our equipment from one landscape to another or one production space to another. I have witnessed a landscape where sheared plants were infected and immediately adjacent there were plants that had not been pruned that were clean (same variety). The maintenance crew was ‘supposed’ to be following proper sanitation. Please take time to clean tools, equipment, trucks and etc. with products like Green Shield, Zerotol, alcohol, and Lysol.
•We must evolve our landscapes into better and stronger cultivars of boxwood. The day of planting large numbers of English boxwood are over. Boxwood blight is only one of the beasts that English Boxwood must fight. It is unfortunately failing over and over in landscapes primarily due to diseases other than boxwood blight.
Boxwood blight is a scary disease but not the beast we feared when it was first discovered in 2011. We continue to believe that it will become a managed disease of the future and that boxwood will continue to be the ‘Aristocrat’ that it has long been.
Until our next update. Happy Spring!