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Subject:
From:
"Malcolm (Tom) Sanford, Florida Extension Apiculturist" <[log in to unmask]>
Reply To:
Discussion of Bee Biology <[log in to unmask]>
Date:
Mon, 6 Jun 1994 14:41:22 -0500
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        USR:[MTS]INTERNET.DIS;19
FILENAME:  JUNAPIS.94
 
            Florida Extension Beekeeping Newsletter
    Apis--Apicultural Information and Issues (ISSN 0889-3764)
                 Volume 12, Number 6, June 1994
 
                   INTERESTING JOB OPPORTUNITY
 
     Although I generally do not include employment opportunities
in this newsletter, a recent one deserves attention.  Mr. Randall
Johnson, past president, American Beekeeping Federation, has an
opening at Honeygold Corporation, 720 Fletcher Dr., Nampa, ID
83686, ph 208/467-5195.  The person sought is one who can provide
a "high level of technical assistance in the areas of evaluating
bee diseases, maintaining adequate parasite control, studying
pollination effectiveness and evaluating queen rearing and bee
nutrition programs."  A degree in entomology, biology or similar
science is highly desirable.
 
     This is one of the few times I have seen an employment
opportunity like this in the beekeeping industry.  If this position
is filled, it may represent a paradigm shift.  In the past, only
those with practical bee experience were sought by the industry and
they often started at the lowest possible wage.  Now that exotic
bee mites, pollination concerns and African honey bees have become
issues of importance, it appears that individuals with a broader,
higher level of training are becoming more desirable.  Whether the
industry has the resolve and/or financial resources to support
employees of the caliber sought by Mr. Johnson, however, remains to
be seen.
 
               AHB MATERIALS AVAILABLE IN ARIZONA
 
     Larry Stanford, program specialist, Arizona Department of
Agriculture reports that an African honey bee information program
is well underway.  A video has been produced entitled "What
Arizonans Need to Know."  Produced in the desert southwest by Dr.
Steve Thoenes, the video is available for $6.00 and carries no
copyright restrictions.  In addition, thirteen (13) fact sheets
have been printed for distribution.  For further information,
contact Mr. Stanford, Arizona Dept. of Agriculture, P.O. Box 234,
Phoenix, AZ 85001, ph 602/407/2982.
 
                 4-H ESSAY CONTEST NEEDS ENTRIES
 
     What does it take to get 4-Hers to sit down and write an
essay?  That's the burning question those at the American
Beekeeping Federation (ABF) and myself are asking after looking at
the results of last year's 4-H essay contest.  Only fifteen (15)
states submitted winners and Florida was not among them.  In
addition, the vast majority of these states only had only one to
two entries to choose from.  There are three top cash prizes each
year ($250, $100 and $50), plus the winner in each state is awarded
a book on beekeeping.  This boils down to one fact:  there's a
great opportunity to win something by simply entering!
 
     The rules for this year's contest have just been announced.
The topic this year is much different than from previous contests.
The essayist is asked to write an original story on honey bees
suitable for a teacher to read to second-grade students.  Suggested
titles include:  The Busy Little Bee, I Like Honey, A Trip to the
Apiary, and My Friend, the Beekeeper.  There's plenty of time to
get a story together for this year's contest; deadline is April 1,
1995!  Full contest rules are available from myself or the ABF
Office, ph 912/427-8447.
 
                    BEE POISONING BY PLANTS?
 
     Reports of severe bee losses in southern Florida this spring
resulted in investigation by Mr. Laurence Cutts and his crew of bee
inspectors at the Division of Plant Industry.  Varroa did not
appear to be the problem and tracheal mite levels were low.
Veteran bee inspector Tom Dowda suggested analyzing gut contents.
Bees' intestines were found to be loaded with pollen from yellow or
Carolina jessamine, Gelsemium sempervirens.  Investigation by the
Beltsville Bee Laboratory confirmed the pollen identification and
revealed no diseases.
 
     Mr. Cutts' analysis of the situation is this:  In most years,
maple and willow bloom overlap.  However, in 1994, there was a gap
between these blooming periods and yellow jessamine (pronounced
like 'jasmine') was virtually the only thing in bloom.  This led to
several questions:  1) Is yellow jessamine nectar (pollen) toxic to
bees?; 2) will bees work this flower if other bloom is available?;
3) If yellow jessamine is toxic, what percent is necessary to be
lethal?
 
     These are not new concerns.  A section in Honey Bees Diseases
and Pests, Second Edition, 1990, edited by R. Morse and R.
Nowogrodzki reveals a great many plants that can be problematic at
certain times in specific areas of the world.  According to the
above volume, yellow jessamine has even been credited with death of
persons eating honey derived from it.  It remains unknown whether
the honey or pollen, or both, are responsible for bee losses.
 
     Another species the book mentions that can do a great deal of
harm is summer titi, Cyrilla racemiflora.  This species is found in
southern swamps and causes "purple brood."  Beekeepers in Florida's
panhandle are well aware of the problems caused by this plant's
abundance.  In some years, summer titi is far more prevalent than
others.  Because it is often localized, the beekeeper can simply
move bees out of the area, or feed colonies.  The latter dilutes
the nectar's potential to do harm.
 
     According to Mr. Cutts, the former strategy is not often
possible with yellow jessamine because it blooms so many places.
He suggests, therefore, that beekeepers monitor locations for this
plant and be prepared to heavily feed sugar syrup and pollen
supplements.  He also suggests a pollen trap might help, although
it remains unknown how much the plant's pollen contributes to the
problem.
 
     According to Dr. Elbert Jaycox, retired from the University of
Illinois, but who published a newsletter, Bees and Honey, for many
years, discussion of poisonous plants brings up important
questions:  1) Why are there toxic plants? and 2) If there are many
such plants, why aren't there more toxic honeys?
 
     Originally, according to Dr. Jaycox writing in 1981, toxic
compounds in plants were considered to be waste products with no
special value.   We now know this is not true.  It is generally
agreed that plants are usually producing these chemicals (called
secondary plant substances) to protect themselves from insect
consumers.   According to Dr. Jaycox, evidence for this theory is
found in the tremendous diversity of insects and plants found on
earth.  The constant development of chemical defenses by plants
coupled with strategies developed by insects to tolerate these
chemicals is a continuing battle between would be "eaters" and
those who might be "eaten."
 
     This process of constant, slow change, called "coevolution,"
is more complex in some systems where the insect not only is able
to detoxify the plant's poisonous substances, but also makes use of
them to protect itself.  The classic entomological example of this
is the monarch butterfly caterpillar.  This larval insect feeds
with impunity on the milkweed plant, which contains cardiac
glycosides, toxic to most other species.  In the process, the adult
butterfly also becomes poisonous.  The characteristic orange and
black color scheme of the adult is a "warning"; birds eating these
butterflies quickly learn the consequences (retching) and avoid
further predation.  In a further twist, the viceroy butterfly,
which is not toxic to predators, has taken on the color scheme of
the monarch in an attempt to mimic its poisonous cousin!
 
     The ability of insects to detoxify secondary plant substances
also confers on them the competency to do the same with human
produced chemicals.  This is one reason why pesticide resistance by
insects is such a common problem in much of commercial agriculture.
 
     According to Dr. Jaycox, this shifting chemistry in plants is
a two-edged sword.  Being poisonous is helpful for survival, but
not so if insect visitation is required for propagation.  Thus,
certain parts of plants may be toxic (leaves, stems), but products
(pollen, nectar) attracting pollinators may not be.  In this
changing mix, Dr. Jaycox says, toxic nectar may be produced in some
plant groups and not in others.  The yellow kowhai tree in New
Zealand and various reports about certain linden trees producing
toxic nectar are examples.  Finally, being poisonous to one kind of
organism (insects) does not necessarily mean this is the case for
others (humans).
 
      Fortunately, Dr. Jaycox concludes, the potential effects of
poisonous plants on bees and humans are reduced in several ways.
In many cases, the plants that might cause problems (rhododendron)
bloom for short periods and when other more attractive nectar
sources are available which dilute the nectar's toxicity.  Often,
bees only visit toxic plants when there is no other nectar to be
had.  This appears to have been the case in the recent poisonings
in southern Florida.  Finally, nectar that is poisonous to humans,
but not to bees, is often consumed for brood rearing or used for
winter stores and thus not available to be harvested by the
beekeeper.
 
                   FLORIDA'S APIARY DIRECTORY
 
     As part of its continuing effort to provide quality service to
the beekeeping industry, the Division of Plant Industry, Florida
Department of Agriculture and Consumer Services, has published its
first Florida Certified Apiary Directory.  This nifty volume
contains an immense amount of material of interest to Florida
beekeepers and others concerned with the apiculture industry.
 
     According to the Directory, it is a snapshot of the industry
as of October, 1993.  Some 1100 registered beekeepers are listed
along with their addresses and telephone numbers.  They are broken
down into groupings based on colony numbers:  hobbyist (1-10),
sideliner (11-200), and commercial (over 200).  All Florida
officials involved in beekeeping regulation and bee inspectors are
also listed with their addresses and phone numbers.  A brief
summary of the apiary inspection law is included along with an
overview of special inspection services provided by the Division.
Finally, a listing appears of other apiary regulatory officials in
the United States and Canada.
 
     The Division of Plant Industry has distributed copies of the
Directory to other Florida agencies and educational institutions.
One has been sent to every county cooperative extension office.
Others interested in obtaining a copy should contact Mr. Laurence
Cutts, Chief Bee Inspector, P.O. Box 147100, Gainesville, FL 32614-
7100, ph 904/372-3505.  Copies are free to Florida residents, but
a small fee will be charged for those outside the state.
 
                     MORE ON BEE ATTRACTANTS
 
     Back in February, 1991, I wrote the following:  "The idea of
increasing pollination potential by applying substances  attractive
to honey bees has been around awhile.  Many substances  [e.g.
Beeline (R)] are based on using sugar to attract the insects.
However, these may also attract pests, as well as pollinating bees.
The use  of pheromones (specific odors) narrows the field by
attracting only certain species.   Honey bee pheromone-based
attractants are now on the market which appear to have  potential
to increase bee pollination, however, hard evidence of their cost
effectiveness is not yet available in all situations."
 
     A few years ago, Dr. Dewey Caron and the University of
Delaware conducted an informal survey on the use of a pheromone-
based product called Bee-Scent(R), produced by Scentry, Inc. There
is evidence that in Virginia and Georgia, the product has increased
apple pollination as well as that on pears, plums, cherries, melons
and  cucumbers.  According to Dr. Caron, Bee-Scent(R) does have a
role to play  under some circumstances, although at about $25 per
acre, another bee colony  may be a better alternative.  As reported
by Dr. Caron, Dr. R.K. Fell in  Virginia observed some increase in
pollinating activity, recommended caution in using Bee-Scent(R).
 
     Now comes a study from North Carolina State University
(Selective Bee Attractants Did Not Improve Cucumber and Watermelon
Yield, HortScience:  Vol. 29, No. 3, pp 155-158, March, 1994) which
compares both Beeline(R) and Bee-Scent(R).  Unfortunately, the
authors found that neither material improved bee visitation nor
significantly improved yield or monetary return.  Does this mean
the materials should not be used under any circumstances?  Not
necessarily.  As I quoted one consultant experienced in this issue
in 1991, "...the material is going to work best under borderline
conditions; that is, when conditions are not completely favorable
to bee activity."  Thus, it will continue to be up to the grower
and beekeeper together to determine how unfavorable conditions must
be before committing themselves to using a bee attractant.
 
 
Sincerely,
 
 
 
Malcolm T. Sanford
Bldg 970, Box 110620
University of Florida
Gainesville, FL 32611-0620
Phone (904) 392-1801, Ext. 143
FAX: 904-392-0190
BITNET Address: MTS@IFASGNV
INTERNET Address: [log in to unmask]

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