Navigating the guidelines for exporting plant material out of a Japanese Beetle (JB) zone such as Ontario can be tricky business, especially with upcoming changes to the Greenhouse-Grown Plant Certification Program (GCP; formerly CGCP).
Also not helping is the general lack of information out there regarding proper timing of JB control products. For example, did you know that NO products are considered effective between May 15 and June 15? This could create problems if you’re shipping outside Ontario in the next month and haven’t treated yet.
To make things easier, I’ve created a treatment “decision tree” and a JB product “cheat sheet” for growers of greenhouse ornamentals.
JB as a “Greenhouse” Pest: Do I Need to Treat?
Japanese beetle are often thought of more as nursery crop or turf pests. But the reality is they have a LARGE host range, feeding on more than 300 plant species,. Greenhouse-grown ornamentals are also susceptible if they get exposed to the outdoors when adult JB are around.
So, if your plants have spent ANY time outside during the flight period of this JB(June 15-Sept 30), or have been in contact with plants that were, the CFIA needs you to spray if you’re planning on shipping outside of Ontario.
Note that plants grown or kept briefly in a cravo are considered to have been “outside”. Better safe than sorry is the mantra here.
This decision making tree was developed by OMAFRA staff in consultation with CFIA advisors. (Of course, always consult your specific CFIA inspector):
Knowing WHAT to use:
This part is relatively simple, given that only THREE active ingredients are currently approved by the PMRA for Japanese beetle control in Canada. These are (with links to their current labels):
- Chlorantraniliprole. The product Aceleyprn is registered for greenhouse use.
- Chlorpyrifos, i.e. Lorsban 4E or Dursban T,
- Imidacloprid, i.e. Intercept
NO other exceptions to this are allowed, as these are the only proven actives against this restricted pest.
Knowing WHEN to use it:
This part can be a bit trickier, for several reasons:
1.Generally speaking, pesticides are less effective against immobile insect stages. This is either because they aren’t ingesting any of the active ingredient or because they don’t have the right receptors. For JB, our registered, soil applied, pesticides have no effect against the pupal and egg stages. Thus, for the window between May 15 and June 15, no pesticide will be effective, and you’ll just be wasting your 1 allowable application for Acelepryn or Intercept.
2. Some pesticides are only effective on smaller larvae of JB, meaning they have a much smaller application window. Intercept, specifically, will not control the older, bigger larval stages of JB, so it must be applied when 1st instar larvae are present.
3. Some products have much shorter residual times than others. Because Lorsban and Dursban only persist in the soil or media for a relatively short time, they can only be applied curatively, close to shipping, to kill any larvae that might be present. Alternatively, Acelepryn and Intercept have long residual times, meaning that they can be applied preventively once JB adults start flying, and will offer protection against any young JB larvae that hatch out in the soil.
This timing application chart was developed by OMAFRA staff in consultation with CFIA advisors to help remove any “interpretations” surrounding JB treatments. If these guidelines are understood and followed each year, and you work closely with your CFIA inspector, then no shipping problems should be encountered.
Both the “JB Decision Flow Chart” and the “JB Control Timing Chart” are meant to be downloaded and printed (see files below) for easier reading. These fit nicely onto a regular 8X11 page to decorate your office with and refer to regularly.
You can also find the most recent information regarding the CCP program in the document below. Dr. Jeanine West at Flowers Canada GOntario (firstname.lastname@example.org) is a great resource for any questions surrounding this new program.