Alternative honey bee nutrition: Beyond sugar syrup

2013 Annual Report for FNE12-752

Project Type: Farmer
Funds awarded in 2012: $14,888.00
Projected End Date: 12/31/2013
Region: Northeast
State: Pennsylvania
Project Leader:
Dr. Petrusia Kotlar Paslawsky
Linden Hill Farm and Apiary

Alternative honey bee nutrition: Beyond sugar syrup


Project Update

Twelve honeybee colonies were installed into a new environment, fed according to traditional and an alternative method and monitored from April-October, 2012. Qualitative testing of the honey was performed to compare products. During the second year of the study, beekeepers/farmers were surveyed to assess interest in honey bee nutrition.  A power point presentation was prepared as a  communication on honey bee feeding practices. This will be offered as part of the outreach aimed to educate beekeepers and promote an effective nutritional alternative to a common practice that is detrimental to honeybee health. 

The general practice of feeding honeybees syrup made of refined sugar cane, beet sugar, HFCS or other artificial solutions, while highly economical in dearth periods of the year, fails to provide honeybees with the broad range of nutrients they might find in natural forage. This method of manipulating the honeybee diet is widely taught to novice beekeepers and practiced in the United States. 

Michurin Biology and Pavlov Physiology prove that “feeding is a kind of mentor and the quality of the food is the factor that influences the formation and growth of the bee” (Curative Properties of Bees and Bee Venom, Naum Yoirish, Moscow, 1959, p. 117.) A poor diet of empty calories could lead to weaker health in honeybees and contribute to the appearance of various opportunistic conditions, such as Varroa mite infestations, and/or a range of other diseases that afflict the hive affecting both commercial and small scale beekeepers nationwide.

Feeding honeybees syrup of cane-sugar or HFCS during a nectar dearth fails to provide honeybees with the nutrients found in nectar.  This study tests feeding honeybees using syrup enriched with infusion of flowers from Tilia sp.  The Linden flower was chosen for its attributes as a natural miticide and its medicinal benefits to honeybee immune health.

Objectives/Performance Targets


The study included procedures of baseline sampling of 12 colonies of honeybees purchased as 3lb. packages from a reputable apiary. 
A sample of 50 bees collected in alcohol from each of the 12 hives was sent to the USDA Agricultural Research Service in Bethesda, Maryland to provide a baseline of Varroa, Nosema and trachial mites. During the course of this two year study, samples will be provided upon death (to the USDA) to monitor infestations of Varroa mites, Nosema and trachial mites. Sticky boards, an Integrative Pest Management (IPM) method, were used for a five day period monthly on all hives to monitor Varroa mites. 

The 12 colonies are labeled “A-L” with the control hives randomly placed. The counting of mites by an unbiased individual (Technical Advisor, Dr. N. Ostiguy of Penn State University agreed to perform this) will present a double blind study. 

Each hive consists of (1) 9 frame deep for brood rearing and (1) 9 frame medium was used for surplus. Foundation will be plastic coated with beeswax . Each hive contains 1 frame of drawn wax comb to allow the queen to begin laying right after installation. 

The hives were situated in an easterly facing barn/shed, an enclosed structure to protect them from winter freezing as an overwintering hazard and access to the inside of the hives will be available all year round. This design  protected the bees from predators such as bears without the need for electric fencing. 

12 packages were installed on April 11,2012. The queens were released after the third day. 

TEST GROUP 1- Four colonies were fed with 2 gallon feeder pails placed directly onto frames. The proposed feed was be 1:1 sugar syrup made with sucrose (cane sugar) combined with prepared concentrated infusion of linden flowers and leaves (Tilia sp.) 

TEST GROUP 2- Four colonies will be fed only 1:1 sugar syrup 

TEST GROUP 3- Four colonies will not be fed. 

The feed was increased to a 2:1 syrup beginning Sept. 2012 for winter preparation. 

Linden flowers and leaves (Tilia cordata sp.) is the specific medicinal/nectar plant from which the infusion will be made. It contains Farnesol, a volatile oil which gives Linden flowers its characteristic smell. It is also an antibacterial and natural pesticide against mites. It contains flavonoid glycocides including hesperidin and quercitin, saponins, condensed tannins, mucilage, manganese salts. Abundant flavonoids such as astragalin, isoquercitin, kempferitin, quercitin, tiliroside, hydroxycoumarins also exist in linden. (PDR from Herbal Medicine, Fourth Edition). The concentrated infusion will be two teabags/pint or 16 teabags per gallon of sugar syrup. 

The Bee yard was visited approximately once a week and utilized a modified summary version of 910531Hive Inspection Sheet.pdf found on the website.(see attached). 

 Data  and the Varroa mites counts have been analyzed and interpreted by the technical advisor. As a cooperator of this study, Dr. Nancy Ostiguy, entomologist of Penn State University, has been a helpful and contributing advisor regarding aspects of honey bee health and procedure. I have met with her twice at PSU campus and have had numerous exchanges with her via email and telephone. 

HIVE J was empty (6/18/12)(not dead out) 
HIVE H was empty (9/8/12) 

On July 8-10,2012 the honey was extracted manually from 10 out of the twelve hives. Samples were submitted to an independent lab for sugar profile testing using Gas Chromatography/Mass Spectrometry(GC-MS)to check for relative sugar percentages. (see attached) 


Twelve colonies were randomly divided in three groups: controls, cane-sugar-syrup, Linden flower infusion of cane-sugar-syrup.  Honeybee health variables were measured including varroa infestations, carbohydrate consumption, and winter survival rates.

From April-October 2012, fed colonies were offered 104lbs (47.2 kg) syrup or Linden- infused-syrup /colony. The consumed amount/colony ranged between 67.25-95.5 lbs (30.5-43.3kg).  GC-MS analysis of honey revealed sucrose levels between 0.16-3.91.

The highest survival rate from April-December was found to be the colonies fed the Linden-infused syrup (100% survived) while only one control colony survived (25%) during the same time period.  Seventy-five percent of the sugar-syrup fed colonies were alive prior to winter but none were alive by March.  Currently the only colony continuing to survive was treated with Linden infused-syrup.

There was a non-significant trend towards fewer mites in the colonies treated with linden-infused sucrose: controls 201.3 + 280.0, sucrose syrup 157.7 + 121.1, and linden-infused sucrose syrup 99.8 + 99.7. Weak colonies, those with the smallest number of bees, had fewer mites (p=0.03). The effect of colony strength on the total mite count was not the same across treatment. More mites were observed in weak untreated (control) colonies than the treated (linden-infused or plain sucrose syrup feed) colonies (p=0.047).

While linden-infused sucrose syrup may have a positive impact on colony health and survivorship, a larger sample size would be required to determine if the impact is statistically significant. As expected, the number of mites in a colony is influenced by how many bees are in the colony. It is interesting that small colonies had more mites if they were untreated than if the were treated. These observations indicate the importance of supplementing colonies with sucrose syrup or otherwise ensuring sufficient forage. We expect supplementation with Linden infusion may provide beekeepers with a method to improve colony survivorship as the honey stores going into winter was less in the non-infused groups compared to the infused group.

Impacts and Contributions/Outcomes


Specific to this farm, this project did not afford the costs of disc and plowing of the fields in the Spring of 2013 as these costs were not anticipated and thus not budgeted for the second year.   The surviving colonies were thus allowed to forage on the natural bee forage of the farm with supplementation with Linden flower and sugar syrup.  Overwintering survival of the honey bee colonies will be assessed in the final report of this project(Feb. 2014).

The outreach of this project was extended by being accepted and invited to be presented at the Apimondia 2013 International Apicultural Congress in Ukraine.  This abstract was reprinted in the January 2014 New Jersey Beekeepers Association Newsletter with the following introduction:
The 43rd Apimondia Congress held in Kyiv, Ukraine on September 29 – October 4, 2013 was ”Beyond the Hive: Beekeeping and Global Challenges”.  The conference had over 8000 participants and was represented by over 100 countries.  I traveled with Dr. Nancy Ostiguy, Associate Professor of
Entomology at Penn State University. Dr. Ostiguy and I presented the results of our NESARE research project in a talk including a PP presentation titled, “Alternative Honey Bee Nutrition- Beyond Sugar Syrup” on Wednesday Oct. 2 during the Bee Health plenary.

A number of individuals expressed interest in our continuing to research the micronutrients needed for bee health and the benefits of natural forage or supplemented sugar syrups. I would like to share the abstract with NJBA and individual districts.

This presentation together with a short video documentary, titled BEE DANCE is scheduled for Essex County Beekeepers  Association and at least one other state branch ie. RVBA or Morris)in January 2014.  

The web site www.thehealthyhive is being updated under the section titled THE HEALTHY HONEYBEE- The Honey bee Study and will provide specific directions to prepare the supplemental feed in time for spring feeding. . This cost effective supplement will provide a improvement to sugar syrup alone.

The results from this project so far should definitely generate a change in the method beekeepers feed honeybees and provide insight to those teaching these methods to new beekeepers.


Dr. Nancy Ostiguy

[email protected]
Assoc. Professor
Penn State
501 ASI
University Park, PA 16802
Office Phone: 8148632872