HINT FOR THE HIVE #125
 
                PRESERVING WOODENWARE IN BEEKEEPING OPERATIONS
 
Traditionally, most beekeepers have used a variety of methods to preserve the
woodenware of their colonies.  This has included paint and hot wax and in
Florida, where the climate and insects (termites) are especially hard on
hives, wood preservatives.  The primary rules to follow to maximize woodenware
life are:
 
(1)  PLACE HIVES ON STANDS ABOVE GROUND to avoid moisture and subsequent
decay.
 
(2)  PLACE HIVES ON STANDS ABOVE GROUND to avoid termite damage.
 
Painting bee hives:  Generally two coats of a good quality latex paint are
used on the OUTSIDE ONLY of woodenware used in beehive construction.  The
inside is not painted to allow the wood to absorb excess moisture produced by
the bees. Special attention in painting hives must be paid to the joints and
exposed end grain.  Many persons soak the ends in water-repellent
preservative before assemblying and painting.
 
Using wood preservatives:  As more and more information becomes available
concerning wood preservatives, it is clear that choices are becoming limited.
Most recent information reveals that the Environmental Protection Agency (EPA)
is taking a closer look at what beekeepers are treating their hives with.  At
least one bee supply outlet has been restricted to one material by EPA.
There is significant evidence that residues from materials have been found in
bees, brood and wax.  Finally, some materials have been found to be highly
toxic to the bees themselves.
 
A paper by M.A. Kalnins and Benjamin Detroy, "Effect of Wood Preservative
Treatment of Beehives on Honey Bees and Hive Products," Journal of
Agricultural and Food Chemistry.  Vol. 32, pp.  1176-1180, 1984 makes some
provocative conclusions:
 
Experiments show that hives treated with creosote, pentachlorophenol (PCP),
tributyl tin oxide (TBTO) and chromated copper arsenate (CCA) were associated
with adverse effect on bees and left residues of preservative chemicals in
bees, honey and wax.  All were also associated with poor winter survival of
colonies.  In particular, PCP translocated from treated hive to honey, bees
and wax (in an increasing order).  Greatest concentration of PCP was in
beeswax (30 to 55 times the controls, which had detectable levels themselves).
This is important as beeswax has a number of uses like cosmetics for which
purity is essential.
 
CCA treatment resulted in elevated arsenic and chromium levels in bees,
arsenic in some cases in the lethal range.  Chromium levels although elevated
were below 1 part per million (ppm) in both bees and honey.  TBTO treatment
resulted in tin levels of several ppm in bees and wax.  The authors suggest,
therefore, that beekeepers not use PCP, TBTO or CCA for beehive treatment.
CCA could be used only on hive parts not in contact with bees.  Any materials
with an arsenic component are potentially very damaging to bees.
 
The authors found few adverse findings resulted from treatments of beehives
with a preservative-free water-repellent solution, however, the treatment did
not appear to provide long-term protection against decay, something often
desperately required under Florida conditions.  Thus, the use of
preservatives is considered essential by many beekeepers in the state.
 
A follow-up article by Kalnins and Erickson, "Extending the Life of Beehives
With and Without Preservatives, American Bee Journal, Vol. 126, No. 7, July,
1986, pp. 488-491. indicates that copper napththenate, copper 8-quinolinolate
and acid copper chromate (ACC) are the best preservative options at present.
 
Copper Napththenate:  Usually sold as a concentrate or solution ready
to use.  The concentrate is 8 percent copper, a viscous green liquid.  For
dip, soak or bush application it usually is diluted with mineral spirits or
paint thinner to a 1 percent copper solution (temperate zones) or 2 percent
copper solution (subtropical zones).  It may bleed through some paints and
should be allowed to throroughly dry before being painted.
 
Cooper-8-quinolinolate:  Less effective than copper napththenate, yet less
hazardous and can be used to preserve wood contacting foodstuffs (refrigerator
cars, food-processing plants).  Can be obtained as a water- or solvent-soluble
concentrate or ready to use.  A solvent-type solution of about 0.045 percent
copper is commonly used for brush and dip treatments.
 
Acid Copper Chromate:  Used in some commercial treatment plants, already
treated wood can be found in certain areas.  It can be applied by brushing,
soaking or dipping, but wood is more durable if pressure treated.  The authors
recommend purchasing commercially treated wood, using dust masks when sawing,
and disposing of scrap in land fills rather than burning.
 
Caution:  Most wood preservatives are classified as pesticides and may be
injurious to humans or animals, plants, fish or other wildlife.  All must be
used according to the label which is the law.
 
Wolmanizing (R):  Pressure treated  or "Wolmanized" (R) wood is available from
many lumber supply houses.  Wolmanizing (R) is a process, and says nothing
about what specific chemicals were used in the treatment.  There have been
reports of significant losses of bees where hives were constructed  using
Wolmanized (R) treated lumber.  It is, therefore, not generally recommended
for beehive use.  Those considering such use should carefully investigate the
actual chemicals used in the treatment process and their potential effects on
bees and resultant hive products.
 
 
 
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Tom Sanford       Extension Apiculturist   University of Florida
Mailing Address:  Bldg 970, Hull Rd., Gainesville, FL 32611-0620
Voice phone  904/392-1801, Ext. 143
FAX  904/392-0190
INTERNET:  [log in to unmask]
BITNET:  MTS@IFASGNV
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