----------
> From: Allen Dick <[log in to unmask]>
> To: [log in to unmask]
> Subject: Nassenheider Evaporator vs Pads
> Date: Sunday, March 02, 1997 4:59 PM
>
> (Note: I wrote this for sci.agriculture.beekeeping and thought it might
be
> of interest here.  Of course I am always interested in being proven wrong
> (that's how I learn), so rebuttals are welcome).
>
> >The Nassenheider evaporator, of which 50,000 have been sold in Germany
> >alone, does not kill queens because it releases the formic in a very
> >controlled fashion and very slowly over a two to three week period.
>
> Some preliminary Canadian research indicates that there may be very
> noticable reduction in honey production when *slow release* methods are
> used in the spring.
>I'm not familiar with this research, but I would be interested in learning
more about it. We are more interested in fall treatment anyway. With our
apple pollination, and early Spring honey flow, it' s really difficult for
us to do any Spring treatment, so if we can get the mites in the fall,
we'll winter better.  Maybe, we could use the pad system in the Spring, but
according to our actual experience of experimenting with both systems,  the
pad system did use more formic, more labor and seemed far more hazardous.
> >The Canadian researchers at The American Beekeeping Federation highly
> >recommended it for "hobbiests." I disagree with them. I think commercial
> beekeepers can use it far more efficiently than the Canadian system. The
> evaporator requires filling only once and uses much less formic.
Treatment
> costs 25 cents per hive - not bad for treating both mites. The Canadian
pad
> system requires much more formic and 3 to four trips to the bee yard.
>
> I have a Nassenheider Evaporator in my hand-- and the instructions -- as
I
> write this.  The Nassenheider Evaparator requires either 100 cm2 or 150
cm2
> (ml) of 60% formic.  Two such units must be used if there is brood in 2
> chambers such there is in Alberta in the fall. This totals 200-300 ml of
> 60% formic.
We found it necessary to use only 100 cm2 in one brood chamber. In October
and November in the Northeast, the brood, what there is of it, is in the
bottom brood chamber, the second brood chamber is chock full of honey from
our fall flow.
>
> Moreover, each unit must be placed fairly close to the brood, I
understand
> that it must be in a half-frame in place of a comb.  Therefore, two
special
> frames are required per normal hive, and they must be inserted in each
box
> of each and every hive, a time consuming process, that mandates extra
> equipment be on hand.  The displaced frames must also be toted somewhere
> for temporary storage.
We didn't use a special frame - just an old one - we didn't have to
temporarity store the displaced frame - we just extracted it.
>
> Dangerous free liquid formic acid must be carried on the truck and
poured
> into a special filler bottle every few units.  Then the units must be
> filled.  Safety practice requires use of a respirator, gloves, and
goggles
> when handling liquid formic.  The units themselves are fairly delicate,
and
> have a wick that is subject to damage in normal commercial rough
handling.
> The wick must be replaced at each use.
We used a Kitchen joy bottle and put it in a five gallon plastic pail -
seemed pretty safe to us. The nozzle fit right into the evaporator. the
only time we were exposed to any formic fumes at all was when we poured the
formic into a funnel. To us the amount of exposure with pads sloshing
around in a pail and then being handled with rubber gloves and tongs seemed
far more dangerous.
>
> Recommendations are to check evaporation rate after 2-3 days and trim the
> wick, if necessary.  This means a trip to pull frames and check.
>
> These are hardly simple, quick processes, and require partially
> disassembling each hive thrice -- once to treat, and once to check, and
> once to remove the unit.  Skilled staff is required for each action.
We did not find any of this necessary - we used the smallest amount of wick
possible to get the maximum time of evaporation. I suppose if you were
treating in the summer the way the Germans are and had hives of different
strengths you might want to do this, but for fall treatment in a relatively
broodless period, we did not find it necessary.
>
> Compare to the Canadian system:  Take a known number of meat soaker pads
> and place in a bucket with a measured amount of formic.  Wait overnight.
> Pour off any excess acid.  Send almost anyone to a bee yard in a light
> vehicle with a pair of plastic or stainless tongs, safety glasses (maybe)
> and some emergency safety equipment, as well as a smoker.
>
> The person removes the outer lid, peels back the sack, and with the tongs
> places a single pad on each top box and quickly turns down the sack or
> plastic.  If no sacks or plastic is used, the bees *should* be smoked
down,
> but I imagine are often not.
>
> The pads are not dripping and no liquid is apparent.  There is no
potential
> for serious leakage.  Most people do not wear goggles or a breather for
> this since there are not many fumes, and no free acid.  Soda and a mask,
> and water should be available though in case of some freak accident.
>
> The treatments should be repeated from three to five times at intervals
of
> anywhere from 4 to 10 days (not critical). Since we often pass yards on
the
> way to working on others, this method does not necessarily mean more
> driving.  The visits are very brief.
>
> Using 30-40 ml treatments, the total dose is 90-150 ml (min) or 120-200
ml
> (max).  This minimum dosage is actually *lower* than the amount needed
for
> maximum treatment using a single Nassenheider Evaporator.  We usually
have
> brood in two or three boxes in Sept, so we would need two for a total of
> *300-400* ml using the Nassenheider Evaporator, but only 200 with the
pads.
>
> >> The danger of queen loss by the sudden evaporation from the pads is
much
> >>
> more.
>
> Although there have been some anecdotal reports, they are usually
> associated with applying the formic on the floor -- not pads -- or using
> incorrect amounts at poor times.  When the recommendations are followed,
> there is no appreciable loss using pads.
>
> >With the Nassenheider, you can treat at the last honey harvest and leave
> >the evaporator in the hive until the first Spring inspection.
>
> This means having a big gap in the frames where the thing sits.  This is
> likely to cause poor wintering (colony death) here in Alberta.
>
> > This results in much less labor and mileage costs than the pad system.
If
> > two men are harvesting a thirty hive yard, it adds about 15 minutes to
> > remove one brood frame and put in the frame with the evaporator on it.
>
> The official instructions require *two* Nassenheider Evaporators per hive
> for my outfit.  That means opening the lower brood chamber -- not a
simple
> task. This doesn't look like a 15 minute job to me.  After all, we still
> have to fill these things with liquid formic.
>
> >If you wanted to get some Fumidil into them, you could come back a month
> later and replace the evaporator frame with a division board feeder
filled
> with sugar syrup.
>
> Sounds like re-arranging the brood chamber in fall -- a prescription for
> hive death where I live.  Besides we are far too busy in the fall to fool
> around with this.
>
> >The formic works in cold weather on the tracheal mite too so I see it as
> >the salvation for Northern beekeeping - we can't all take our bees to
> >Florida.  There is a whole page on these evaporators in the 1997
Betterbee
> >catalogue - they cost about two varroa strips!
>
> Soaker pads cost 1.5 cents each for a total of 7.5 cents -- if we go the
> whole 5 trips.  We use much less formic, have less danger, cut labour
cost
> to a trivial amount, and ensure that, since there are multiple visits,
that
> each hive will get treated at least most of the trips.  None will be
> accidentally missed.
 
Four or five trips to the bee yards may be possible in Sasketchwan where I
imagine your beehives are all close together and  placed in a manner
whereby you can hit a lot of them in a single day, but in the Northeast, it
is getting harder and harder to find rural locations for bee yards, and
ours tend to be hither and thither, so that multiple trips to a bee yard
are just not economically feasible.
>
> The Nassenheider Evaporators cost *much* more, use more acid and are not
> proven in North American conditions.  Moreover, most experts agree that
> formic alone will not always control varroa sufficiently that Apistan
will
> never be needed.  Usually there is a recommendation to monitor mite
levels
> and rotate treatments where varroa is a problem.
 
This is certainly true and most Canadians I have talked to seem to be using
apistan strips as well. The Nassenheider evaporators cost  less than two
strips.  If someone in this country could perfect them and mass produce
them, they ought to cost less than one strip. They are not the perfect
delivery system, but then, for my operation anyway neither is the pad
system, and having actually compared both systems and factoring in mileage
and wear and tear on my truck and the cost of my labor, the evaporator is
by far the most efficient and ecomomic for me to use, but it may not be for
everyone.
 
>
> Of course, I am not sure about how many of the Nassenheider claims to
> believe, since, for one thing, the literature that comes with my
> Nassenheider Evaporator claims 'an acaricide effect of appr. 90% was
> achieved in sealed brood cells'.  (If this is truly the case, then we had
> better watch out because the +Tracheal Mites+ in Germany now seek out
> sealed brood, and not predominently 1 to 4 day old bees as they do here).
 
This is fascinating - could you elucidate - how do they do it - do they
actually penetrate the cappings?
>
> Anyhow, all funning aside, we can use pads spring or fall, save tons of
> money and fussing, and still get a good honey crop, something that slow
> release methods cannot guarantee when they are used in spring.
>
> And we still have the many thousands of dollars (10,000?) that we would
> have spent on Nassenheider Evaporators, if we find that next year there
is
> a fantastic breakthough.
 
Formic seems pretty good to me, in whatever form it is used. The sooner we
get it approved in the U. S.,the sooner huge amounts of tactic and maverick
will cease being used. One thing you might enlighten me on, Alan, is the
whole question of
immunity to chemicals.  It is alleged that the mites cannot develop an
immunity to formic as they are doing to fluvalinate. Is this so and if so,
why?  I think that formic is a simpler compound than fluvalinate.  If you
don't know the answer, perhaps someone with a background in chemistry can
give us the answer.
 
 
 
>
> Allen Dick                                  VE6CFK
> Rural Route One, Swalwell, Alberta  Canada T0M 1Y0
>      [log in to unmask] & [log in to unmask]
>        http://www.internode.net/HoneyBee/