From my experience 2 or 3 short parallel cuts about 2 inches in length
is sufficient.
 
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        If you make the feeding area too big the weight of the feeding bees
tends to cause the baggie to leak. Also slits that are too long tend to
compromise the bags abiltiy to hold the syrup.
 
        I think some of the early reports of the bees taking the syrup really
fast were due to lots of bees on top of the baggie causing the syrup to leak
and then just run out the entrance. This can be avoid by keeping the slits
shorter.
 
        I really like the baggie feeders as they don't suffer from leaking that
inverted pails suffer from when the air inside warms and expands. The only down
side is that for feeding with cool temperatures the bees have to leave the
warmth of the hive to get to the top of the baggie. This is not the case for
pails inverted over the hole of the inner cover.
 
        Regards,
 
                Jim Moore