Cranberry Fruitworm IPM Refresher!

Wednesday, June 13, 2012

Hi folks,

I've finally gotten out to see some bogs and have had some feedback regarding the growth stages in your bogs.  The heat and sun this week are definitely moving things along!  We should be nearing the end of the first generation of blackheaded fireworm and sparganothis, and I know some of  you have already been treating for cranberry weevil.  Now that we are rapidly approaching bloom, (and probably reached it in some of the warmer areas of the province!) I thought it was time to refresh everyone's memory on how to calculate % out of bloom to time your cranberry fruitworm sprays:  

Collect 10 uprights from at least 5 areas of the field and count the # pinheads, fruit, hooks and flowers. 

   Total pinheads + fruit                                X 100     =   % Out of Bloom
total hooks, pinheads, flowers, and fruit

You should time your first cranberry fruitworm spray at the 'egg stage'.  Generally that means for Stevens - 3-5 days after 50% out of bloom,  Ben Lear - 5-7 days after 50% out of bloom, and for Howes or Early Blacks - 7-9 days after 50% out of bloom. 

Five days after the first treatment, randomly collect 50 fruit per acre  (or a minimum of 200 per bed for smaller acreages), and use a microscope to record the number of eggs.  On beds sized 1-5 acres, the threshold is 1 egg, on larger beds add 1 egg per every 2 acre increase, for example, the threshold on a 7 acre bed would be 2 eggs.   If egg numbers trigger a spray, spray immediately, if no eggs are found, continue to scout for eggs every 3-4 days until mid august. 

We have discovered an issue with linking to the PMRA website for labels - apparently they change the coding every 48 hours so my links have only been working for that amount of time (not very convenient!!!!).  I will make every attempt to link labels directly to the company's website in the future so the links will work, but this isn't possible in every case. 

If you need to find a label, please use the PMRA label search link below to find what you are looking for:

The easiest way to search is by using the product name option from the drop down box in the search field, type in the name of the product you are looking for, click on the submit search requirements button at the bottom and when the list of products come up you click on the registration number to bring up the full label.  Occasionally there are a number of different formulations for a particular product name so you may have to search through a couple of labels to find the one that is registered for your crop and pest!   Happy Searching!