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When asked what t~pe hone~ their bees have produced, most beekeepers end up auessina wrona. Pollen is a honey bee 's m ajor sou rce of proteins , fatty s u bstances, mineral s, a nd vitamins. It is essen tia l for the gro wt h of larva e a nd you ng a d u lt bees . A honey bee removes po llen from an an the r by u sing her tongu e a nd mandibles . While crawling over ft.owe rs , po llen a lso a d he res to her "ha iry" legs a nd body. Th e honey bee co mbs pollen from her head, bod y, a nd forward legs , mixes it with nect ar from her mou th, a nd transfers it to th e corbiculae, or "pollen ba sket ". on her ba ck pair of legs . When "loa de d" with po llen , s he will retu rn to he r hive. Once at the hi ve , wo rk ers p a c k t he po lle n in to s pecial com b cells loca ted in the ce ntra l po rtion of th e hive surrou nd ing the brood a re a . To p revent bacteri a l growt h a nd d elay poll en germ ination, a ph ytocid a l acid is a d de d to the pollen as it is pa cked in to the co m b . Ot her e nzymes produced by worker bee s a re a lso ad ded to prevent a naerobic m et abolism a nd fer menta tion thereby a d di ng to the lo ngevity of the s tored pollen . On ce it is com plete ly proc essed for s to r age, th e po llen co m b Citrullus lanat us . s to rage a rea, refer red to a s "bee b read ," is rea dy for la ter consumption by the bees . The p rotein sou rce needed for rearing one worker bee from la rval to a dult s tage requ ires a p proximately 12 0 to 14 5 m g of pollen, An a verage bee co lony will collect a nd s tore a bou t 44 to 12 5 pou nds of po llen ea ch year. In mo st cases, the primary foraging sou rc es for pollen are the various in sect -pollina ted (entomop hilous) plants ho ney bees visi t for nect ar. However, honey bee s will a lso visit a number of s pecies of non-nectar p roducing, win d -po llinate d (anem ophilous) plants to co llect pollen. Anemophilous types s uch as Quercus s pp . (oak) , Celtis s p p. (ha ckberry), Cary a (pecan or hi ckory) , many s pe cies of grasses [Poa ceae], a n d the wind -pollinated co m posites [As tcracea ej . s uch as ra gweed (Ambro s ia s PP.I, a re a ll im po rtan t poll en s ou rces for fora ging honey bees. Accord ing to th e 1868 ed ition of Paxton 's Botan ical Dictionary, both "melissa" a nd "m elitta" mean "a bee ." Th e Aprill 2014

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scien tific name of the Eu ropea n honey bee is Apis mellifera L. Th e wo rd "mellifero us" co mes from the Latin word mellifer (honey) a nd the s u ffix -o u s meaning, "having, full of, or characterized by." Th e In tern a tional Com m ission for Bee Resea rch d efin es the word "me lissopalynology", to reflect the s tu dy of pollen in honey, which is the tenn tha t m ost people no w u se . Th e pollen recovered in a honey sample a rrives there from a number ofs ou rces. When a honey bee la nds on a flower in sea rc h of n ectar, s ome of the flower's pollen is d is lod ged a nd fa lls into the nectar tha t is then su cked u p by the bee a nd s tored in h er s to m ac h . At the sa m e time , ot her po llen gra ins from flowers that are vis ited become a tt ache d to the bee's ha irs , legs , antenna , a nd eve n the eyes . Lat er, so me of the pollen that wa s s ucke d into her s tomac h will be regurgitated with the co llected nect ar a nd d eposited into ope n co m b ce lls of the hiv e. Whi le s till in the hive that same honey bee may groom her body in an effort to remove the en tangled pollen on h er body. Duri ng tha t p roces s s ome po llen ca n fall directly in to open com b cells or on to a re a s of t he h ive whe re ot her bee s may track it in to regions of t he h ive where u n ripe honey is s till exposed . Airb orne . .po llen is a no ther potentia l, but often mi nor so u rce o f po llen in honey . Airborne pollen produ ced by plant s not u sually vis ited by honey bees ca n en te r a h ive on wind cu rren ts. These wind -po llin a ted types of po llen a re u sua lly few in number, when com pared to the poll en ca rried in to the hiv e by worker bees ; nevertheless , thos e po llen types can regularly en te r a hive on a ir cu rre n ts a nd can settle in a reas where open com b ce lls a re being filled with nect ar. Some a irbo r ne po llen mi ght a lso be d eposi ted into rip ening honey when beekeepers open the hives for in spection or remove frumes for honey extra ct ion. Fin ally, during the extractio n p rocess po llen from some of the pollen s to rage ce lls in a com b mi ght be rupture d thereby mix -

BEE CULTURE

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ing tha t pollen in with the extracted honey. When a sked what ty pe of honey th eir bees hav e produced , mo st beeke ep ers e n d up guess ing wrong . I hav e been exam in ing honey sam ples from the United States a n d m any other regi ons of th e world for over 35 years . Durin g th at t ime I h a ve look ed a t ove r 2,500 hon ey sam ples a nd I h a ve found th at a bo u t 60% of t he tim e the bee keepe r guesses wrong . Many of th e guesses may seem logical to th e beek eep e r, but they a re wrong. Wha t often hap pens is th at a beekee pe r will see bees flocking to so me plant in bloom a n d will assu me th a t th ose n ec ta r sources a re th e basis for the hon ey produced in hi s hives . So me beek eep er s will rely on th e co lor or taste of produced honey as t he best way to identify a nd label their honey, but sad ly, eve n thes e gu es ses a re often wrong. It tu rn s ou t that the easiest a nd safes t way to verify the typ e of honey bein g produced is to ex tract a n d exam ine the pollen . Th at system has been used effectively for ne arl y a centu ry and it rema ins the lea st expen s ive, fast est , a nd u su ally the best way to provi de certa inty to t he ide ntity of a h on ey sa m ple. Never th eles s, ju s t ident ifying what pollen types occur in a hon ey sam ple doesn't tell the wh ole s tory a bou t th e honey being test ed or about th e im portance of different nect ar sou rces u sed by th e bee s to make th e honey . The key to th e correct identification of specific honey typ es is much more complex. The story begin s during the early 19405, wh en two California scientist s working for th e USDA, Frank Todd a nd George Vansell, d ecid ed to exa m ine th e relationship betw een t he pollen in th e floral so u rces visited. by hon ey bees and th e la ter recovery of those same pollen types in th e honey th e bees produced [Todd a n d Van sell 1942). First, th ey wan ted to calculate th e number of pollen grai ns that one wou ld ex pect to find in one cubic centime ter (ce) of nectar collected from ea ch of over 2,000 different plant type s in California . Th ey discovered tha t for so me major necta r so urces very little pollen is trapped in th e n ectar a n d the re fore very littl e of that pollen type is collected by visiting bees . The result is that those pollen typ es a rc ra rely found in honey sam ples even wh en t he hon ey is m ade primarily from those n ect a r sou rc es . At the other Aprill 2 0 14

extre me t hey found th a t the nectar of some plants con ta ine d thousands of pollen grains per cc . For exam ple th ey found that for premium honey made from th e nect a r of bla ck locust (a ka , acacia) (Robinia p seu.doacacial, th e necta r of th at plant contai ne d only a bout 1,670 pollen grains per cc of nectar, bu t for willows (Salix spp.j, th e nectar con ta ine d a bou t 80, 000 pollen grains per cc of necta r . For most species of citru s pla nts (Citrus s pp. ) th e nectar con ta ine d a bou t 25,000 pollen grai ns per cc of ne ctar. Their stu dy was the firs t to produce a table of da ta showing th a t not all nectar so u rces are created equ al in tenns of the a mou nts of pollen they co n tai n, a nd by inference it means that the amou nt a nd types of pollen in honey will also vary accord ingly. Knowin g th at each ne ct ar source co ntains different a mo u n ts of pollen a nswere d only th e first part of th e problem. The second part of the probl em focused on how much pollen from eac h ne ctar so u rce could a honey bee remove duri ng the return trip to th e h ive. Todd and Van sell kn ew that ea rlier res earch by Wh itcomb a n d Wils on s h owed t hat a bee 's h oney stomach ca n remove u nwanted debris, incl u di ng pollen a nd fungal s pores , which might germinate a nd s poil the ga thered ne ctar be ing convert ed into hon ey. To test how efficien t honey bees were, th ey fed a caged hive only di luted ho ney th at con ta ined 5,20 0 sta r thistle (Centaurea ap p.] pollen gra ins per cc of fluid . Later, th e sealed h oneycom b ce lts produced by th e caged hon ey bees were removed a nd exa mine d . They found th at instead of th e original 5,200 a mou n t, th e newly produced hon ey containe d only 1,200 star thi stl e pollen grains per cc. Those results su rprise d Todd and Vansell beca use they expec te d th e poll e n co nce n tration of the newly produced honey to be high er , not lower , than th e a mou n t they were fed . The on1yJogical conclusion was th at th e significa nt reduction in pollen conce n tration wa s th e resu lt of th e filtration a bility of a bee's hon ey st omach , whic h wa s a pparently far mo re effective than m ost researc he rs had realized. Th ey a lso discovered that th e a mou n t of pollen a bee ca n rem ove from th e n ectar she collected dep ends on th e amount of tim e betw een when th e nectar is collected and wh en she depos its the neetar in t he hive. The longer th e interval , BEE CULTURE

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