Back to top

IPM Message for Cranberry Growers: Jul 18, 2012

Jul 18, 2012

Some growers are reporting heavy infestations regarding fruit inspection and CFW pressure. Talking with the Ent lab, that concurs with what they are finding. "Most bogs have nothing but 1 in 10 will have a big (heavy) infestation similar to your numbers. We can't say whether the dead eggs are from the whole egglaying period or just the last week but where there is pressure it continues, new eggs continue to be laid." They also caution to remember NO more Altacor now that it is after 7/15! Delegate can be used for Spag but do not exceed 19.5 oz per acre per season. The Ent lab has gotten several calls about cranberry weevil so if you are still sweeping, you may be seeing these as well. Belay can be used but only after the bees are gone as it is highly toxic. Check for handler restrictions for this insecticide as some handlers are prohibiting its use. Lorsban continues to be a poor choice for most bogs as weevils are resistant to this OP. 

I have gotten a few calls about applying Callisto. You are permitted only 2 applications total to the bog area. This counts whether applied by boom, chemigation or any combination of application methods. Even if you only apply 4 oz/A each time (thus staying under the 16 oz/A limit), you can only make 2 applications. If you chemigated Callisto and If a portion of your bog did not get treated for some reason (blocked head, etc) and you have weed escapes, you can spot-treat that portion of bog. You should carefully note this in your pesticide records so it does not read as 3 applications to the same piece. Callisto has a 45-day PHI. Poast has a 60-day PHI. 

Treatments for fairy ring can go out in July. Ferbam is used but must be applied by July 31 and can only be used once. Treat 3 ft beyond the advancing ring of dying vines and 2 feet within the line. Sul-Po-Mag or K-Mag can be used to help vines recover mid-August through October. Remember that Abound and Indar are considered high risk materials for resistance development; rotate other fungicides into your schedule as needed.