Enhancing honey production with clover: Innovative methods to use white and alsike clover in Vermont hay fields

Enhancing honey production with clover: Innovative methods to use white and alsike clover in Vermont hay fields

Summary

A decline in honeybee populations in Vermont over the past few decades has been attributed to many factors including mites, disease and a loss of nectar and pollen resources. An important stressor on honeybees in Vermont is the lack of food available to them throughout the summer.     The goal of this project is to increase the acreage of flowering clovers that provide sustained nectar flows during this critical summer period. In 2013, two farms collaborated in establishing field trials to test the feasibility of including white and/or alsike clover in their hay fields. The first trial was planted on May 10 in Weybridge, VT over seeding white clover into a predominately grass hay field using different seeding rates and methods. In 2014, we found the site to be predominated by volunteer red clover with little white clover with not observed differences in our previous treatments. Due to these changes.  Another on-farm strip trial was planted in late May 2013 in Bridport, VT comparing pure alfalfa to alfalfa mixed with one of two different white clover varieties or with alsike clover at two seeding rates. As similar trial was planted in small plots at the University of Vermont in August 2013.   Both trials were intensely monitored for clover head production, yield and quality and some bee activity in 2014.  A website was developed, http://pss.uvm.edu/vtcrops/?Page=research/SARE_Enhancing_Clover_Nectar.html, to post updates on the project as well as any outreach materials developed from the project. An update of the project was presented at the Vermont Beekeepers Association Farm Show meeting in January 2014 and at a New England Pollinator Workgroup meeting in June in Durham, NH.

Objectives/Performance Targets

The first objective is to test the feasibility of improving nectar flow for honeybees by introducing Dutch white clover into grass hay cropping systems and assess its impact on flower production and foraging honeybees. On April 10, 2013, two field trials were implemented. The first was a strip trial at the Duclos-Thompson Farm, a diversified livestock farm, in Weybridge, VT.  This trial was set up in a field that has been in hay for well over five years that is adjacent to a bee yard managed by Champlain Apiaries. The soil type is Vergennes clay, moderately well-drained. The dominate forage species is a mixture of common forage grasses (orchardgrass, bluegrass, timothy), red and white clover and some weeds particularly smooth bedstraw. Treatments were the same as outlined in the proposal including a no-treatment control plus four different seeding scenarios using Dutch white clover: two seeding rates, 2 vs. 4 lbs./a using two methods of seeding, no-till planted with a Haybuster 107C drill. Strips were 50 feet wide and 150 feet long. Due to the size of the strips and field, there were only two replications of each treatment arranged in a randomized block design.    

A second trial for Objective 1 was seeded into an existing grass hay trial located at the Horticultural Research farm at The University of Vermont. Since we did not have access to a no-till drill, we seeded two rates of Dutch white clover, 2 vs. 4 lb/a, compared to a non-planted control in narrow strips using a Carter small plot forage seeder. These were seeded along the edges of each grass plot that was part of an existing study. The soil type is a Deerfield fine sandy loan which has a drainage classification of well-drained. Visual observations were made throughout the 2013 growing season there was no evidence of white clover germination. We conclude that the site was too dry and not conducive for this type of overseeding. We plan to observe the seeded strips in 2014 before making any final conclusions.

Our second objective is to test the feasibility of improving nectar flow by growing mixtures of various early maturing legumes with alfalfa managed for hay and assess its impact on flower production, honeybee activity, forage yield and forage quality. Our hypothesis is that early maturing legumes such as medium white clover and/or alsike clover will bloom before the alfalfa is ready to cut. To test this hypothesis, we implemented two trials in 2013. The first one was a strip trial planted at the Huestis farm in Bridport, VT. The site is a Vergennes moderately well, drained clay. Mr. Art Huestis has managed this site for over 40 years successfully growing alfalfa for his dairy herd. The study includes seven treatments replicated four times two seeding rates of three clovers. Each plot is 30 by 180 feet. Mr. Huestis planted the whole area on May 3 with a single seeding rate of alfalfa at 10 lb/a. Clover treatments were then broadcast planted within each respective plot using a hand spinner spreader. The clovers included ‘Pinnacle’ and ‘Crusade” white clover and ‘common’ alsike clover seeded at two rates, 2 lbs vs 4 lbs. There is also a non-clover control consisting of alfalfa only. Due to inclement weather in 2013, there was only one cutting made in early August. In 2014, we collected clover head populations from each plot every one to two weeks starting in June after the first harvest was made. We also collected yields and made bee activity observations.

As part of Objective 2, a second small plot study was seeded August 22, 2013 at the UVM Horticultural Research Farm with similar treatments as those at the Huestis farm. Besides the same treatments as at Heustis farm, it also includes a mixture of alfalfa with all three clovers combined seeded at two different seeding rates.   In 2014, we collected clover head populations from each plot every one to two weeks starting in June after the first harvest was made. We also collected yields and made bee activity observations.  

For Objective 3, a website was developed and posted to provide updates on the research and demonstrations. The URL is: http://pss.uvm.edu/vtcrops/?Page=research/SARE_Enhancing_Clover_Nectar.html

Accomplishments/Milestones

January 2014

• A project overview and update was presented at the Vermont Beekeepers Association annual meeting (n = approximately 200 people)

April 2014

• Honeybee colonies were place at each farm site by Champlain Valley Apiaries.

May 2013

• Visual observations were made for all studies.
• Plots at the UVM site were hand weeded for curly dock and white campion.

June to Sept 2013

• Collected data on clover flower counts at the Heustis and UVM site approximately once every one to two weeks from June through September. Collected measurements to estimate yield at both locations.
• Champlain Valley Apiaries maintained bee colonies to assure active, healthy hives.
• Presented an overview of the project to the New England Pollinator Habitat Working Group (a Northeast IPM supported project) in June and August
• Presented an overview of the project at a SARE Pollinator field twilight meeting sponsored by John Hayden on July 29.

Nov/Dec 2013

• Data was analyzed and samples processed for quality analysis

Impacts and Contributions/Outcomes

For Objective 1 at the Duclos study site, no measurements were collected in 2014. The whole field was dominated by volunteer red clover with little appearance of white clover. There were no visual differences in each of the treatment strips. This was not surprising since we found no differences in clover head counts the season before between the control strips and the seeded strips.

For Objective 2 for the Huestis study and the UVM study, the sites appeared in good condition at the beginning of the 2014 season and were monitored for clover bloom, bee visits, yield and quality in 2014. At the end of 2014, the data is still undergoing analysis but preliminary data shows the following:

• White clover was much more prolific at producing flowers compared to alsike clover. After the each harvest, white clover would produce bloom within the first week to 10 days after regrowth and would continue to bloom until the next harvest.   Alsike clover flowers heads took longer to develop than white clover and would not have a significant number of flower heads until at least two to three weeks after a harvest and it took three weeks to get a significant population.

• There were also differences in white clover cultivars probably due to their sensitivities to day length. At the UVM site, ‘Crusade’ had more flower heads in June but tapered off in July and August while ‘Pinnacle’ had significantly more in July and August. Extrapolating from 20 inch square quadrats, the alfalfa/ ‘Pinnacle’ white clover mixture seeded at a 15 pound alfalfa and 3 pound white clover rate per acre, we measured a flower head population that ranged from 200,000 to 288,000 per acre.

• There were no statistical differences in yield between many of the clover mixtures with that of pure alfalfa. The three way clover mixture and the ‘Crusade’ mixture was lower by a .5 to .75 tons per acre compared to the pure alfalfa but other mixtures were similar. Note that this is the first full harvest year of these stands. It will be important to evaluate the persistence of the stands over the next 2 years.

• It appeared at the Huestis site where plots were much larger that the most persistent clover was in areas of the field in which the alfalfa was thin probably due to the excessive rain and wet soil in the seeding year. This will be further evaluated in 2015.

• Although there was plenty of clover bloom in June and July in some of our treatments, we observed very few honeybees working these plots. First, there were ample supplies of nectar and pollen from other sources this year including a lot of volunteer red and white clover in surrounding fields. Honeybees tend to forage nectar sites that are abundant and consistent. With plots that varied in species and cultivars as well as flower populations, it was not surprising to not see and abundance of bees. However, we did observe more in August working the plots. We observed both honeybees as well as native bumblebees.

• Samples were collected to evaluate any differences in forage quality of the clover mixtures compared to pure stands of alfalfa. Analysis will be complete in the winter of 2015.

• At this time, we cannot make a strong recommendation to blend white clover with alfalfa for high quality, high yielding forage. It looks promising but needs further evaluation. It is also clear that planting the right cultivar into the mix is critical.

Collaborators: