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["Jim Fruth" <jfruth@tds.net>]

   I used to wonder why I never got ahead of the raspberry/blackberry cane 
borers.  Every Fall, when I cut out the dead canes, I religiously 
scrutinized primocanes for swellings on stems, cutting out and destroying 
infected canes.  I do it again in late Spring/early Summer when cane borers 
are actively infecting new, growing, canes.  Every year there seems to be as 
many (or more) than the year before but I think I just figured out why.
   I had always centered my attention on the obvious swellings that 
circumvent canes.  These swellings are almost all located at the bottom 1/3 
of the canes.  This year, looking higher, I'm seeing a different pattern. 
Cane borers are infecting the upper portions of primocanes with a different 
type of girdling.  Instead of the grub circumventing the cane and ending 
where it began, the upper cane borings are girdlings in spiral patterns. 
These girdlings span 1-1/2, or more, of the cane's circumference.  The worst 
part of it is that they are somewhat difficult to see because they are not 
as pronounced and lower cane borer swellings tend to be.  I observed some 
swellings only after the light struck them at a favorable angle.
   If we do not cut out these infected canes, they (the canes) will die 
just before the fruit ripens and that is FRUSTRATING.  Even if there was a 
spray recommended for controlling them, we couldn't use it anyway because 
many infections occur during pollination.  Sanitation is still the 
recommended method of control and the best time to do it is now, while 
primocanes are dormant.

Jim Fruth
Brambleberry Farm
Pequot Lakes, MN  56472
For jams, jellies & syrups:
www.bberryfarm.com
(877)265-6856 [Store]
(218)831-7018 [My Cell]