Rats vs rats

Jane McGary janemcgary@earthlink.net
Fri, 03 Sep 2004 19:55:03 PDT
Arnold wrote,
I have heard that there are some rodenticides that don't allow secondary 
poisoning such as was described  in the death of the borzoi.  I think it 
may be zinc phosphide that reacts with the  acid in the gastrointestinal 
tract and releases  a gas that poisons the rodent.  The gas does its thing 
and then moves on and secondary poisoning is not a problem.  Of
>course I would be hesitant about this until I had researched it a bit more.

Zinc phosphide was one rodenticide mentioned by the state agent I 
consulted. It is not used in bait, as far as I could tell -- it is applied 
to the soil underneath a sheet of plastic, and poisons the rodents 
directly. It can be obtained in Oregon only by people who have state 
pesticide applicator's licenses.

The poisoned grain I have heard mentioned was said to be treated with 
strychnine. This does cause secondary poisoning. I thought it likely that 
the voles would die underground in their tunnels and not be available to 
scavengers, but I don't have any of this poison, anyway, and am unlikely to 
use it. There MUST be something appropriate to use, though. I've lost very 
rare and valuable bulbs at times.

The feral cats frequent the bulb frames and surely deter some rodent 
activity there, although their leavings are disgusting. I don't keep 
domestic cats because I disapprove of their predation on wild birds.

Jane McGary
Northwestern Oregon, USA

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