CAPPings – March 2020

March 5, 2020


Well, here it is, the first ever edition of our newsletter, CAPPings, “Happenings of the Clemson Apiculture and Pollinator Program.”  We at Clemson University are excited to write this new chapter in our legacy of beekeeper education and pollinator protection.  Along with a brand new website and an apiculture Facebook page, this newsletter is a first step in developing a completely new extension program for South Carolina’s amazing beekeepers.  The program also plans to engage the general public on the topic of pollinator protection and invertebrate conservation.  This combined approach is intended to protect the critical ecosystem services that honey bees and native pollinators provide to South Carolina.

Ben Powell, Apiculture and Pollinator Program Coordinator

Over this first year, our new coordinator, Ben Powell, will be working on several objectives in addition to launching the website, facebook page and newsletter.  

Needs Assessment Already underway is a needs assessment survey for beekeepers.  This survey will help guide the program to ensure we are addressing the needs of beekeepers statewide.  Ben is visiting with all of the local beekeeper associations to discuss plans for the program and to issue the survey.  The survey also will be made available on the website and over email very soon. If Ben has not yet visited your local association, please contact him to schedule a talk.

Extension Pollinator Focus Group We have convened a group of extension agents, researchers and regulatory officials to focus specifically on beekeeping and pollinator issues in South Carolina.  This group will improve pollinator education training within the Extension Service and will help guide and deliver new extension programs in apiculture and pollinator conservation.

SC Beekeepers Association We are working with the South Carolina Beekeepers Association to help with its mission to support and educate beekeepers.  This includes participating in the executive board meetings, the master beekeeper program committee, and spring and summer conferences.

Technical Trainings We plan to provide advanced trainings and citizen science projects for Master Gardeners and Master Naturalists. We are developing trainings for landowners and solar farm contractors on how to install and maintain pollinator habitat at the state’s rapidly expanding number of solar energy farms.  We are working with Soil and Water Conservation Districts on this year’s education theme “Where would we bee without pollinators?” and we are presenting at libraries, schools, professional conferences and workshops to advance honey bee and pollinator awareness.

4H Honey Bee Project The 4H Honey bee project is an independent study project for youth development.  We are working to expand participation and youth learning about beekeeping in general.

Demonstration Field Sites We are expanding our apiaries and field demonstration sites to provide more opportunities for hive and forage management education and research.

We also are working behind the scenes to address concerns with pesticides, land use changes, pests, diseases and invasive species with the intent to protect honey bees and pollinators.  We look forward to sharing more on those efforts in future editions.

We appreciate your interest in our program and encourage you to visit our new website, join our facebook page and provide us with feedback on how we can serve your educational needs and address the challenges that concern you. 


An extremely mild and wet winter has made for interesting conditions across the state.  In some areas, spring seems to have already arrived with trees like redbuds, crabapples and black cherries in bloom, and it is only the end of February. Yellow jessamine, a principal indicator of the start of the nectar flow, is beginning to bloom. Reports from the lowcountry and midlands indicate nectar flows have begun, but warm spells intermittent with cold nights are leading to frost damage on many flowering trees.  Basically, it appears we are on the cusp of the full nectar flow.

Frost damaged flowers of a redbud tree

Inside the hives the queens are laying at maximum rate, and populations are expanding rapidly.  This means that two serious management problems are likely, 1) starvation or 2) swarming.  Because it is near the end of winter and populations inside of the hives are growing rapidly, most colonies are working through their stored honey and pollen quickly.  Depending on the size of the colony and the amount of reserves they have, many colonies may be running critically low on food reserves.  If warm, sunny weather persists, then there may be enough flowers for the bees to ride-out this period until the full nectar flow begins, but we are several weeks away from the typical start of the nectar flow.  Some colonies may be one hard frost away from not having enough to eat.  For this reason, beekeepers should be checking the weights of their hives and probably should be feeding.  Several feeding methods work, including powdered sugar on the inner cover, fondant on the top bars, candy boards, or heavy syrup (2:1 sugar:water) in a division board feeder are all decent winter feeding methods.  Remember, we tend to have frosts all the way through March, so you may need to continue feeding through the next month.

Active bees on a cool day in February

The other major concern for this time of year is swarming.  Strong hives may be preparing to swarm.  There are few external signals that indicate the colony is making early preparations.  Bearding at the hive entrance even on cold, rainy days may indicate congestion in the hive which is a contributing factor to swarming.  Probably the best way to determine if the colony is in the early stages is to lift the brood box(es) and inspect for swarm cells (queen cells along the bottoms of the frames).  If you find swarm cells, then the colony has “decided” that it will swarm.  In this case, you probably should consider making an emergency swarm split by removing the queen and half of the brood comb plus a couple frames of honey/pollen and place these in a new box.  This procedure mimics the conditions that occur after swarming and can disrupt the urge to leave the hive.  It does not always work, so it also makes sense to place swarm traps.  These should not be placed right next to the apiary, rather they should be placed no closer than half a kilometer from the apiary in various directions.  A couple hints for placing swarm traps are 1) elevate them off the ground at least 5 meters, 2) place them in landmark trees, 3) make sure the trap is shaded, and 4) make sure water (stream, pond, wetland) is within 200 meters.

Last, I observed that my demonstration colonies never broke the brood cycle this winter. In this case, varroa mites are able to continue reproducing, so it will be critical to check your mite loads early this year.  There are very few treatments that can be used during the nectar flow with supers on the hives.  These include HopGuard, MAQs (formic acid), installing/removing drone frames, opening screen bottom boards, and breaking the brood cycle (a method that is not recommended for honey producers).  For more information about Varroa mite treatment options, check out the Honey Bee Health Coalition’s fact sheet.

The forthcoming spring should be an exciting time.  Hopefully you have prepared your wooden ware and are set for when spring springs!  We wish you the best in this year’s nectar flow!

Brad Cavin (right) speaking with SC beekeeper

For this first edition, we thought it would be best to introduce you to Brad Cavin, the apiary inspector for South Carolina.  Brad has been working to protect South Carolina’s bee operations from infectious diseases and Africanized honey bees for many years. As a Department of Plant Industry (DPI) inspector, working with beekeepers was only one part of his job duties, but that has changed.  Clemson regulatory services recognized the need for a position dedicated to the state’s growing beekeeping industry and decided to instate Brad as the full-time apiary inspector for the state.  In this roll, Brad is charged with enforcing the South Carolina Honey Bee Act and the department’s related regulations, which are designed to protect South Carolina’s bees from infectious diseases and pests.  In this position Brad oversees the regulatory activities of Clemson University’s Department of Plant Industry Apiary Inspection Service programs in South Carolina which…

  • Conducts random inspection of beekeepers/queen breeders and investigate various trouble calls (swarms, mites, foulbrood, colony collapse, etc.).
  • Establishes protective or restrictive quarantine(s) because of disease or deleterious exotic species; seize bees, equipment, pollen or honey, if necessary, to enforce bee laws and regulations. 
  • Collaborates with Clemson University’s Apiculturist to develop education programs and practical research projects that will assist beekeepers with management of honey bee diseases, parasites, and pathogens.
  • Educates the public by giving talks about bee removal and the laws that regulate the honey bee industry.
  • Attends local, state and national apiculture meetings as appropriate.
  • Issues certificates of inspection for queen breeders; issue certificates for exportation and importation commerce for colonies of honey bees and pollination permits.

To further assist beekeepers, Brad participates is national bee health surveys and has developed lab resources to diagnose infectious bee diseases here at the university, which greatly improves accuracy and response. We are excited to work with Brad and the Apiary Inspection Program to engage and serve South Carolina’s beekeepers.  

This month’s native is Yellow Jessamine (Gelsemium sempervirens), South Carolina’s state flower.  This evergreen vine is an iconic symbol for our state, chosen because “its delicate flower suggests the pureness of gold; its perpetual return out of the dead of winter suggests the lesson of constancy in, loyalty to, and patriotism in the service of the State (SC State Legislature 1929).”  No matter where you go in the state you will find it growing along roadsides and forest edges.  It is easily recognizable this time of year because it launches the spring season with a dazzling display of yellow flowers before most other trees and flowers awake from their winter slumber.  It also has a sweet fragrance that makes it desirable as an ornamental plant for gardens.

Yellow Jessamine flower (Gelsemium sempervirens)

But, yellow jessamine has a dark side, especially for honey bees.  This plant is toxic.  Yellow jessamine contains alkaloid toxins in its leaves, stems, roots and even its nectar.  Despite this toxin, honey bees will forage on its nectar, because they have not evolved the ability to sense the toxins.  Occasionally, we receive reports of piles of dead bees at hive entrances in early spring, a time of year when insecticide use is uncommon.  Analysis of some of these colonies has indicated large concentrations of yellow jessamine pollen in the honey, suggesting that the bees are foraging heavily on this plant. 

It is difficult to determine how much this plant is contributing to honey bee mortality, so Clemson’s Apiculture and Pollinator Program is working with phytotoxin researchers at the university to explore ways to isolate the toxins and determine if they are present in honey in the hive.  This season we will collect yellow jessamine nectar and pollen to determine the toxin profiles and then test honey from suspected hives to determine if gelsemine poisoning can be diagnosed in bees.

For the most part, gelsemine poisoning has only temporary effects on honey bee colonies, causing a brief period of mortality in early spring.  This only occurs in locations where there are large populations of yellow jessamine and very few other nectar sources.  It appears that honey bee colonies with good winter stores and alternative forages are not affected significantly by this plant.

This section will be dedicated to discussing ongoing research projects or recent publications that we think will be of interest to South Carolina beekeepers. Here is a selection of research projects published this month.

Oxytetracycline (Terramycin) inhibits protein digestion in bees, especially when fed poor protein diets such as might be occur when pollinating a single plant species du Rand et al. Antibiotic treatment impairs protein digestion in the honeybee, Apis mellifera. Apidologie 51, 94–106 (2020).

Study finds coumophos residues in new comb and cappings constructed five months after a single treatment with CheckMite strips.  This suggests that wax from colonies treated with coumophos should not be used for making new foundation or coating plastic foundation. Kast, C., Kilchenmann, V. & Droz, B. Distribution of coumaphos in beeswax after treatment of honeybee colonies with CheckMite® against the parasitical mite Varroa destructor. Apidologie 51, 112–122 (2020).

Introducing Osmia bicornis, a commercially available mason bee, increases early fruit set in sweet cherries.  This means more consistently mature fruit earlier in the season which is an advantage to fruit growers. Ryder et al.  (2020) Impact of enhanced Osmia bicornis (Hymenoptera: Megachilidae) populations on pollination and fruit quality in commercial sweet cherry (Prunus avium L.) orchards, Journal of Apicultural Research, 59:1, 77-87, DOI: 10.1080/00218839.2019.1654062

Chinese researchers determined that several essential oils have acaricidal activity on varroa mites at levels that do not harm honey bees.  Two oils (rosewood and fennel) were explored further for testing as fumigants in hives and showed some promise.  These products are not approved mite treatments in the US. Zheguang Lin, Xiaoling Su, Shuai Wang, Ting Ji, Fu-Liang Hu & Huo-Qing Zheng (2020) Fumigant toxicity of eleven Chinese herbal essential oils against an ectoparasitic mite (Varroa destructor) of the honey bee (Apis mellifera),Journal of Apicultural Research, 59:2, 204-210, DOI: 10.1080/00218839.2019.1688493

Honey bees on a Clemson hive

28 March 2020 – 4H Honey Bee Project Field Day at the Charleston Community Bee Yard, West Ashley, SC

5 April 2020 – Charleston Honey  and Bee Expo in Mt. Pleasant, SC

24,25 April 2020 – Journeyman Beekeepers Course in Conway, SC

13 June 2020 – Bees in the Backyard field day at Midlands Beekeepers Association in Lexington, SC

22-25 July 2020 – SC Beekeepers Associaiton Summer Conference in Anderson, SC

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