April 2019 - 8

INDUSTRY NEWS
from americanhort to you
Box Tree Moth: Coming Soon to a Boxwood Near You?
BY JILL CALABRO, PH.D., SCIENCE & RESEARCH PROGRAMS DIRECTOR,
AMERICANHORT AND HRI
A new insect pest, box tree moth, will likely make itself known to the
U.S. soon after being found in a few Toronto area landscapes in fall
2018. An online, citizen science group first reported the sightings after
a homeowner submitted photos of the pest that were then verified by an
entomologist. This marks the first reports of this pest in North America;
however, the findings remain unconfirmed by Canadian Food Inspection
Agency (CFIA).
How Did It Get to Canada?
Our story begins in Germany, in the vicinity of a shipping center
that receives materials from China. That's where box tree moth (BTM)
was first found in the EU in 2007. The details of BTM introduction to
Germany are unknown, but it is most likely linked to importation of
infested boxwoods from BTM's native range, China. Since 2007, it
quickly spread to nearly all countries in the EU, mostly through the
movement of infested boxwood in the nursery trade; this is the likely
explanation of how it made its way to Canada as well.
No natural predators exist in the EU. Not even birds and other animals
will eat the caterpillars because they contain toxins deemed distasteful.
Once introduced to an area, damage to boxwood is severe. In just a
few years, large areas of native boxwood trees and forests have been
devastated. Between 2009 and 2010, German officials attributed over
90 percent defoliation in the country's largest box tree forest to BTM.
Boxwood can survive defoliation as long as the caterpillars do not eat
bark on the main stems. Once this happens, boxwood lose ability to
obtain necessary nutrients and water, while becoming more susceptible
to fungal and bacterial infections.
Getting to Know BTM
As with many insect pests, the most destructive life stage is larvae, or
caterpillars in this case. Damage is caused by larvae feeding on leaves
(aesthetic damage) and bark (physiological damage). Infestations are
flagged by skeletonized leaves, frass deposits, and webbing created by
caterpillars for protection during feeding and pupation. Adults are moths
with a wingspan of about 1 ½ inches, and wings are either white with a
dark brown border or brown with small, white spots.
The ideal temperature range for BTM is from 70 to 92 °F, but activities
are known to occur outside this range. Eggs hatch when temperatures
are at least 52 °F, and larvae regularly survive winter temperatures
below -22 °F in parts of China. Not even a polar vortex can slow it down.
Depending on temperature and light levels, two to four life cycles per
year are common in the EU; each lasts around 45 days.
What Can We Do to Protect Ourselves?
The Animal and Plant Health Inspection Service (APHIS) has been
closely monitoring for the potential introduction of this new pest to
the U.S. for over 10 years and created new pest response guidelines
in preparation. One possible course of action that APHIS could take
involves creating a federal order requiring inspection and certification of
boxwood entering the U.S. from Canada. Traps and monitoring programs
are other examples. Researchers are unsure how quickly BTM will spread
in the U.S. Box tree forests do not exist here; so, less host material may
translate to slower or less spread.
Controls are available, including pheromone traps, pyrethroids,
chlorantraniliprole, and Bacillus thuringiensis (Bt) products (Xentari,
DiPel). Eradication in North America could be a viable option in North
America, but only if we, as an industry, are vigilant and stay prepared for
any suspicious-looking boxwood damage. Please report anything that
even remotely looks like it could be BTM and help protect our boxwoods.
The Horticultural Research Institute (HRI) continues to monitor BTM
as part of its ongoing Boxwood Initiative. Outreach on emerging pests
and diseases is another example of how HRI helps the industry stay
informed on issues impacting their bottom line.
Product information is in no way a product endorsement. Please consult
product registration and label for the most current use information.
DÜMMEN ORANGE'S
BASEWELL TO INCLUDE
WESTHOFF PRODUCTS
FOR 2020
Dümmen Orange and Westhoff
plan to partner to offer the Westhoff
line of spring annuals in the Basewell
product form for spring of 2020 to
the North American market.
Dümmen Orange introduced Basewell, a groundbreaking new product
form, to the North American market in 2018. After a successful inaugural
commercial season in 2019, Dümmen Orange is focusing on broadening
the Basewell offering to include new partners like Westhoff to add more
options and breadth to the assortment from which growers can choose.
Christian Westhoff, owner and CEO, regards this opportunity as a
strategic next step. " Basewell is a technological leap forward for our
8 APRIL 2019 GPNMAG.COM
industry, and we at Westhoff are excited to be able to have our products
offered in this new form. Growers will benefit from the ease of using
our products in a new, extremely flexible product form that will help
improve input quality. We see this as being another solution to meet our
customers' needs. "
Alongside adding Westhoff genetics to the Basewell program, Dümmen
Orange will increase its overall Westhoff portfolio by 35 percent. New
additions for Spring 2020 include the brachyscome Cottage series and
new novelty varieties of Chameleon and Candy Shop calibrachoa. The Hot
lobelia and Crazytunia petunia series also expand with new offerings and
improvements for 2020.
" In the business of spring annuals where the market demands freshness
and novelty, the synergy between Dümmen Orange and Westhoff means
growers can plan a complete spring program, for example, with hanging
baskets, that will deliver the best and most colorful varieties at retail, " said
Emily Mason, Dümmen Orange IPT Lead for Bed and Balcony.
http://www.GPNMAG.COM
April 2019

Table of Contents for the Digital Edition of April 2019
