Hallo,
die Finnen träufeln die Oxalsäure auch im Frühling - gleich nach der Reinigungsflug. So eird zweimal geträuflet - im November und im Frühling. Zweimal träufeln - einmal zuviel, gilt nur wenn die Bienen können nicht raus.
Hier der Auszug aus der Beitrag von Ari Seppäla in BEE-L List vor 2 Tage. Etschuldigung das auf Englisch - weder ich habe Zeit, noch mein Deutsch ist perfekt, das ich übersetzen kann.
Weiss nicht ob es gilt für Deutschland wo die Brutpause viel kürzer ist.
mfg
Ainars
" Date: Wed, 2 Dec 2009 10:00:32 +0200
From: Ari Seppälä <***@***>
Subject: Re: oxalic time...
>.......
As a advicer I always recommend the beekeepers to mix like this: 75 g oxalic
+ 1 kg sugar + 1 litre water. Easy to remember. To use ready sugar liquid is
more work cleaning the measuring cup than making it with water and dry
sugar.
My friend is going for resistant bees and he gradually stopped oxalic
treatments. From his data we saw that oxalic gave surprising good drops of
mites with just 10 ml/ big hive. If you give the same small amount of oaxlic
in more diluted solution t will not work as well.
So in summary I would say that you can give less than recommended oxalic
treatment and still get reasonably good results, but variation in efficacy
will be bigger than in recommended amounts.
During last few years the trend here has been that many are going for fall
and spring treatment with tricling. This way they use only oxalic against
varroa. Spring use is just after first flight before the bees start to raise
brood in bigger amounts. Some years you can treat in spring without any
brood, but time window is small.
Treating twice in fall will result in big problems. It was hard for me to
believe that bees that can not tolerate 2 treatments in fall with 1 - 2
months apart, do tolerate treatment in November and again in March. It must
be in more time and chance to fly."