NEIGHBORHOOD GARDEN FOR JANUARY 16, 2010


Fruit and Vegetable Crop Pollination

BY MARION ELLIS

Extension Apiculturist (BEEKEEPER),

 University of Nebraska-LINCOLN


     Cross pollination, or the transfer of pollen from flower to flower, is an essential step in the production of many fruit and vegetable crops. Insect-pollinated crops produce small amounts of sticky pollen and rely on pollinating insects to transfer pollen from flower to flower. Inadequate pollination can result in deformed fruit or no fruit to harvest.
     Honey bees are the most important fruit and vegetable crop pollinators. However, populations of honey bees have diminished during the past decade due to the Varroa mite, a recently introduced parasite which has become a major pest in the region. The Varroa mite has caused extensive losses in managed colonies, and it has increased the labor and expenses required to maintain colonies. Of perhaps greater significance, the mite has killed most of the wild (feral) colonies which formerly existed in tree holes, hollow walls of buildings, and other protected cavities. This means that fewer honey bees are available in towns, cities and the surrounding countryside where homeowners have previously benefited from their pollinating activity.
     Fruit and vegetable growers can encourage native pollinators to help cover the current “pollination gap.” Providing backyard habitat for native pollinators such as bumblebees, leafcutter bees, and mason bees may become a necessary part of both urban and country gardening and fruit production. Alternately, honey bees can be kept to provide both pollination and a crop of honey. While Varroa mites have decimated wild populations of honey bees, skillful beekeepers can protect and care for honey bee colonies without suffering losses.
     Commercial growers should act quickly to ensure fruit set if pollinator activity is inadequate.  Studies show that six bee visits per blossom are required to obtain a uniform set of well-formed fruit for most apple varieties.
     Fruit and vegetable growers who have enjoyed the benefit of wild honey bee pollinators may find it necessary to manage pollinators to obtain good fruit yields in the future. Bee pollination is as essential as fertilizing, watering, pest control and other management practices. The following are things that growers can do to encourage pollinators:
          1. Plant forage plants such as sweet clover, Dutch clover, purple vetch, sunflowers, pussy willow, alfalfa or goldenrod to attract and sustain pollinators, and let them bloom so the bees can feed on the flowers.
          2. Plant shrub roses, raspberries and other brambles with hollow or pithy stems to provide nesting sites for solitary leafcutter and mason bees.
          3. Make an artificial leafcutter or mason bee habitat. Untreated 4" x 6" lumber works great. A 1/4” or 5/16" diameter hole can be drilled in smooth wood on 3/4 inch centers, 2.5 to 8" deep depending upon the size lumber used. A hole smaller than 1/4” or larger than 5/16” will attract undesirable bees and insects. A 5/16" diameter hole is important for attracting Mason Orchard Bees. Do not drill completely through the lumber. Attach a roof to provide protection from the midday sun and rain. Outside surfaces may be painted or stained, but do not use wood preservatives.

          Alternately, soda straws of similar diameter can be trimmed to the same dimensions and placed in half-gallon milk cartons.  Larger holes will not be acceptable nests, and smaller holes will result in a high proportion of male bees which do not pollinate. Drilled boards or straws should be placed in a shelter 3 to 4 feet above the ground which faces Southeast. Do not hang in a tree or on a post. The bees will find the blossoms - that is their life's work.

          This is a very good project for kids!!!!
          4. Small compost piles can be left around the yard or garden to encourage bumble bee nesting. Compost piles left for bumble bee habitat should not be turned during the period in which bumble bees are active.
          5. Keeping honey bees can be a fascinating and rewarding hobby or side-line. While other pollinators may be important in the pollination of small orchards, honey bees are still the most easily managed pollinator for growers requiring large numbers of pollinators.
          If you want to know more about pollinators and pollinator management attend one of the “Beginning Beekeeping” Workshops. These will be offered on February 27, 2010 at the Adams County Extension Office in Hastings , Nebraska , and March 13, 2010 at the Kimmel Education and Research Center in Nebraska City . Cost to attend a workshop is $20.00 per person and $6.00 for each additional family member. Registration includes lunch, refreshments, and a workbook for new beekeepers. Preregistration is required.

          A 3-day Master Beekeeping Workshop will be offered in Ithaca , Nebraska at the Agricultural Research and Development Center Headquarters Building on June 10-12, 2010 . Registration for this workshop is $100.00 and includes 5 meals, a workbook, a cap, and refreshments.

          If you have questions or want more information about any of these workshops contact your local County Extension Educator or Marion Ellis , Extension Apiculturist, University of Nebraska-Lincoln at 402-472-8696 or mellis3@unl.edu.

(Apiculture is a specialty within the Entomology Department dealing with bees.)

          “Keeping bees will raise your understanding of the natural world and the interrelatedness of all living things.  In learning about the importance of honey bee pollination, you will realize how living things depend on other living things and that, while a few insects are pests, many are essential to our survival. Keeping honey bees with a young person is a fabulous way to teach them to be patient, gentle, and good stewards of the natural world.” Marion Ellis

Copyright 2010

For more information on building a bee habitat go to:

http://www.ars.usda.gov/Main/docs.htm?docid=10743 ((Build a Nest Board, Agriculture Research Service, USDA)

http://king.wsu.edu/foodandfarms/documents/MasonBee.pdf (Orchard Mason Bees, Washington State University Extension Service in King County )

http://gage.unl.edu/artificialhabitatfortubenestingbees (How To Build Artificial Habitat For Tube Nesting Bees, UNL Extension in Gage County , NE )