Subject: VARROA ala natural

From: [email-masked] (Andy Nachbaur)
Date: Wed, 10 May 1995 00:51:00 GMT

originally in conference IN-BEE-LIST on (Wild Bee's BBS)
                    ----------------------------------------
From: [email-masked]
Date:         Tue, 9 May 1995 13:41:58 +0000
Subject:      Re: VARROA

Mike Bipsham wrote:

> Here in the UK varroa is now endemic.  As an  ecologically  minded
> hobby  beekeeper,  I am unsure if I want to continue beekeeping if
> it means having to treat the hives with insecticide.  Does  anyone
> know of alternative treatments?

    Please Note:  I  posted  recently  about  some  'soft'
    chemicals  we  are  using.  Someone asked me to expand
    more.  I'm unable to add very much  and  we're  'just'
    beekeepers  not  a  research  establishment, however I
    shall report what I can.   Gordon

------------------------------------------------------------------

IBRA ([email-masked]) supply an  information  pack  on  Varroa
that makes good & useful reading.

Most of the alternative methodologies are fairly labour  intensive
but  feasible.  IMHO the main alternatives are:

    1) Drone Trapping.

    Divide a frame into three sections, fit  a  starter  strip  of
    foundation  and place this near the outside of the brood nest.
    The bees will (probably :-) draw drone comb on this (which  is
    what  we  want).  Varroa prefer to lay in drone comb so we can
    cut these sections out in rotation (one per  week)  whilst  we
    find  a  significant  infestation.  Makes a significant energy
    loss for the colony as they put a lot of work into the  drones
    we kill.

    2) Trapped Queen.

    Trap the queen onto a (preferably unused) frame using a  frame
    sized  cage  of QX material to trap her on that frame.  A week
    later transfer her onto another similar frame and do it again.
    A  week  later  do it again, then remove and destroy the first
    comb which by now will be sealed.  A week  later  release  the
    queen  and  destroy  comb  two, in the final week destroy comb
    three.  A powerful method because the mites have no choice but
    to  lay  in  the trapped frames.  Knocks the colony back a bit
    though.

    3) 'Soft' Chemicals.

    Debatable what's 'soft'.  Formic acid is  the  'usual'  stuff.
    It's  a  natural and degradable pesticide used by ants.  It is
    however pretty nasty stuff  for  us.   Handle  with  _extreme_
    care.   Lactic acid (naturally from milk) is used in a lighter
    concentration (5% sprayed lightly onto the bees &  combs)  and
    is  supposed  to  work  in  a  similar but less risky way than
    Formic.  I do know that it knocks down quite a lot  of  mites.
    Our   Association   here   (Basingstoke  UK)  have  also  been
    experimenting with icing sugar or french chalk dusted onto the
    bees  & combs.  The function of these is supposed to be purely
    mechanical -- it gets onto the sticky pads on the feet of  the
    mites,  they lose their grip and slip off.  I've looked pretty
    closely at quite a few and I think it's true because I can see
    eight  white  feet.  It seems likely that vigourous fanning by
    the bees may help this happen.  We don't know if there are any
    side  effects  --  whilst  the  materials are pretty benign in
    themselves, the drying effects may be significant.  All  these
    are basically contact only on the adult mites, so treatment is
    about every four days for four treatments.

The IBRA pack offers some other methods including heat treatment.

Regards,
--
Gordon Scott          [email-masked]   Compuserve
100332,3310
                      [email-masked]
Basingstoke Beekeeper [email-masked]

<EOF>                    -30-

---

From: [email-masked] (ANTHONY MORGAN)
Date: Fri, 12 May 1995 13:03:50 GMT

>From: Gordon Scott  via Andy Nachbaur
>Subject: VARROA ala natural
>Date: Wed, 10 May 1995 00:51:00 GMT

Greetings fellow beekeepers everywhere!

I am located in mid-Norway not far from Trondheim, latitude
63-26 North (look it up on a map!).
Varroa is now widespread in southern Norway (endemic would be
too strong a term yet) but has yet not spread to mid-Norway
because of:-
a) restrictions on movement and sale of bees and used hive material etc.
and
b) the convenient existence of a mountainous area to the south of us.

I am interested in other's experiences with "natural" methods of
combating varroa and any recommendations/tips. We are barred from
using "non-natural" insecticides etc by virtue of the norwegian law.
The more complicated 'mechanical' methods appear to involve too
much work and disturbance to the colony and the 'soft' chemical
methods do not seem suitable either for the reasons that follow:-

We are lucky enough to have two honey seasons, one for so-called
summer-honey based on wild raspberries followed imediately by one
for heather honey that finishes at the beginning/middle of September.
Due to the problems with overwintering with heather honey we take
the full honey quantity and feed the colonies on sugar syrup. This
is, in fact, economically advantageous as honey is worth about seven
times the cost of sugar per kilogram! However, this means the most
suitable time for treatment with formic acid or lactic acid is when the
temperature is dropping rapidly day by day such that we sometimes
have difficulty feeding the colonies.

>    loss for the colony as they put a lot of work into the  drones

It is interesting to note that many of us here use the three section
empty frame as a 'swarming barometer'. (without any starter strip
of foundation normally) This has been a known technique for many
years (e.g. Handbook of Beekeeping, R. Lunder, 3rd. ed. 1980).
Lunder says (translation):-
"Use of the building frame is recommended in apiaries where one
does not systematically use more radical methods for restricting
swarming. It takes some work to shift the super and take out the frame
on a weekly basis but on the other hand it takes significantly more
work to check the whole brood chamber for swarm cells. And as
described earlier; the building frame tends to damp down the
tendency to swarm to some extent." (as wax production is ongoing,
the queen is provided continously with extra egg-laying space and
the larva, if present, absorb some of the colonies food production)

Cheers
Tony Morgan
[email-masked]

---

From: [email-masked] (David J Trickett)
Date: 13 May 1995 08:37:35 GMT

: originally in conference IN-BEE-LIST on (Wild Bee's BBS)
:                     ----------------------------------------
: From: [email-masked]
: Date:         Tue, 9 May 1995 13:41:58 +0000
: Subject:      Re: VARROA

:     3) 'Soft' Chemicals.

:     Our   Association   here   (Basingstoke  UK)  have  also  been
:     experimenting with icing sugar or french chalk dusted onto the
:     bees  & combs.  The function of these is supposed to be purely
:     mechanical -- it gets onto the sticky pads on the feet of  the
:     mites,  they lose their grip and slip off.  I've looked pretty
:     closely at quite a few and I think it's true because I can see
:     eight  white  feet.  It seems likely that vigourous fanning by
:     the bees may help this happen.  We don't know if there are any
:     side  effects  --  whilst  the  materials are pretty benign in
:     themselves, the drying effects may be significant.  All  these
:     are basically contact only on the adult mites, so treatment is
:     about every four days for four treatments.

: Gordon Scott          [email-masked]   Compuserve

How much powder do you need, and how evenly does it need to be distributed?  
When I read about these treatments a month or so ago, here in the news 
group, it occurred to me that maybe the way to go (if these work) is to 
cut an auger hole, or set thereof, in appropriate places at the tops of 
the brood chambers or perhaps the supers.  Where exactly would depend 
upon what area needs to be dusted (I don't know).  Anyway, If these holes 
were plugged with greased wooden dowels, it would be relatively easy to 
remove the dowels and insert a turkey basting type device filled with the 
powder of choice, and squeeze away.  This would obviate the need for a 
full scale manipulation if the powder could be sufficiently dispersed.  

There are some other, similar approaches but they are still dependent 
upon the answers to the following questions:

1) Do you need to dust the frames individually, or is dusting along the 
top bars sufficient?

2) If the answer to the above is that dusting the top bars is sufficient, 
do you just dust the top supers, all the supers/deeps, or just the deeps?

I am trying a variety of approaches this year and plan to analyze the 
results using contingency tables.  I'll certainly publish the results, if 
they are worthy of dissemination.

Dave

---

From: [email-masked] (Allen Dick)
Date: 14 May 1995 16:03:54 GMT

On the matter of dusting with icing sugar:  We are warned when using it 
with TM for AFB control not to get it into open brood beacause of its 
dehydrating effect, it is allegedly lethal to larvae.

I imagine there is some amount which could be tolerated.

Someone should do an experiment to see if and how much icing sugar it 
takes to kill open brood and if the dusting being considered is a problem.

A beekeeper here used to administer TM/icing sugar mix with an old 
Cynogas dust gun in the entrance.

I tried it and used that method for a while.  Don't recall any particular 
brood mortality, but then I wasn't watching closely, and a lot of 
mortality can go unnoticed.

Allen

---

From: Gordon Scott <[email-masked]>
Date: 22 May 1995 22:15:29 +0100

In article <[email-masked]>
           [email-masked] "David J Trickett" writes:

> :     mites,  they lose their grip and slip off....
> 

We treat them by dusting both sides of each frame, trying  to  coat  the
bees  and  trying  not to dust the brood.  We just dust whichever powder
>from  a shaker for a few seconds per frame side.   Mechanical  knock-down
seems  to  take  about an hour.  We place a tray under the brood nest on
which to catch the mites as they fall and then remove the tray after the
hour and deal with the still live mites as we see fit.

I doubt that putting the dust along the top bars would work, I think  we
need to get quite a lot distributed quickly and evenly. It's quite possible
that some form of dust sprayer might work

We tend here just to dust the brood nest because we  wish  to  avoid  as
best  we  can,  getting  any  contaminants  in  the honey.  I don't mind
getting icing sugar in there, but I don't like the idea  of  talc  --  I
believe  the stuff's safe enough (although breathing _any_ dust is not a
100% good idea), but it isn't what I want in my end product.

BTW, talc *seems* to work better against the mites that icing sugar.

> they are worthy of dissemination.

If you can get enough real information I'm sure many will be interested.
One  problem  many  of  us  have is that, often at best, our results are
subjective.  By that I mean, I might get a good knock-down  because  the
treatment's  good,  or  because  the  colony  is heavily infested (maybe
because the previous treatment was _not_ good).  Unless in a position to
measure this pretty accurately, things have to remain subjective.  Daily
natural mortality can be a useful guide to infestation  level,  but  its
accuracy  is  fairly  poor.  The arival of infested bees from absconding
colonies can "blow all the sums right out of the water".

-- 
Gordon Scott	[email-masked]		100332,3310 on CompuServe
Newsletter	[email-masked]	ditto
		Beekeeper, Kendo Sandan, sometime sailor.
		Basingstoke, Hampshire, RG22 5HP, UK