tree fruit and berry pollination in virginia (and the mid-atlantic by extension)
DESCRIPTION
This program is a slightly expanded and updated version of a presentation given to Virginia beekeepers in April 2010. It covers basic terminology of pollination (cross-pollination, pollenizer, etc.), common fruit grown in the mid-Atlantic, basics of flower structure and varietal issues relating to pollination needs, honey bee (Apis mellifera) colony recommendations, and highlights non-Apis bees important for pollination. It also highlights fruit families and relationships to native flora, providing fruit for thought regarding pollination in the New World prior to introduction of honey bees. Research results regarding the role of non-Apis bees are summarized, along with buzz pollination, and land management suggestions to support pollinator populations.TRANSCRIPT
Bee Pollination of Tree Fruits & Berries in Virginia
Nancy Adamson, Richard Fell, Donald MullinsVT Entomology Department
(an expanded version of a presentation to VirginiaState Beekeepers on16 April 2010)
Program Overview
Tree fruits & berries grown in Virginia
Colony recommendations
Pollination research on non-Apis bees & a little more pollination biology
honey bee to peach
Rosaceae (rose family) apple & crab apple, pear,
serviceberry, quince caneberry (raspberry,
blackberry, black raspberry, wineberry)
peach, plum, nectarine, apricot
strawberry
Other fruit families Cucurbitaceae (cucurbit):
watermelon, musk melon Annonaceae (custard-apple):
pawpaw Grossulariaceae: gooseberry,
currant Ebonaceae (ebony): persimmon Caprifoliaceae (honeysuckle):
elderberry Actinidiaceae (Chinese
gooseberry): kiwi Passifloraceae: passion flower Cactaceae (cactus): prickly pear
Ericaceae (heath family) blueberry, cranberry,
huckleberry
Insect pollinated* fruit grown in Virginia
* Grapes and mulberries don’t depend on insects—can you think of others?
Most fruit crops benefit from cross-pollination Some crop varieties* require cross-pollination
apples, blueberries, cherries, kiwis, persimmons, sunflowers, caneberries**, and hemp (McGregor 1976, Free 1993, McConkey 2009)
*Variety is a horticultural term for plants of one species with specific characteristics• Red Delicious, Fuji, and Pink Lady apples• Bing and Rainier cherries
two apple varieties
Many caneberries** are sold as self-fertile
** Caneberries are raspberries, blackberries, black raspberries, etc.
bumble bee on blackberry
halictid bee on raspberry
Autumn Bliss (l) & Josephine (r) raspberries
Self-fertile plants—cross-pollination improves size and shape
Cross-pollination requirements/recommendations vary tremendously by variety Pollenizers are the pollen “donors” Crab apples are often used as pollenizers in apple cultivation• Bill Frieman of Doe Creek Orchard in Pembroke, VA prefers to use
compatible saleable varieties
Here, 2 varieties are in different rows
Notice larger flowers in left variety
Cross-pollination needs vary by variety
Check with nurseries for pollenizer requirements
Especially important to match pollenizers to the harvest variety by bloom time
Many of these cherry varieties are self-sterile
Some are cross-incompatible* (for ex. Emporer Frances, Bing, & Kristin)
* Cross-incompatible varieties cannot pollinate one another
http://freedomtreefarms.com/charts/cherry/
cherry pollination chart
Pollination requirements and flower structure:more ovaries require more visits
Prunus spp.: plums, cherries, peaches, apricots & almonds very early spring flowering, single* ovary forms “stone” fruits, drupes
*One visit may be adequate if the female parts are receptive, the pollen viable, and the varieties compatible.
single ovary
pollen
Flower parts may mature at different times—promotes cross-fertilization (vigor in the big scheme)
Malus spp.– apples and crab apples 5 ovaries need multiple visits, generally proterogynous (pollen is
shed after stigma is no longer receptive--prevents self-fertilization)
apple flowers & andrenid bee
stigma
(female)
anther(male)
ovaries
Aggregate* & accessory fruits (multiple ovaries & visits)
Rubus spp. – caneberries (drupelets) Fragaria spp.– strawberries (seeds are achenes)
raspberry
strawberry
blackberry
*Fleshy fruit forms from ovary. Accessory fruit (strawberries and apples) flesh forms from non-ovarial tissue.
Vaccinium spp.—blueberries & cranberries Ribes spp.—currants, gooseberries Asimona triloba--pawpaw
True berries—single ovary, multiple seeds & visits
cranberry
gooseberry
blueberry
* fetid flower odor attracts fly and beetle pollinators
photo courtesy of Margie Adamson
pawpaw*
Dr. Fell* recommends 1 to 2 honey bee colonies/acre for tree fruit (~1 to 3 are recommended for berries)
Some self-sterile, cross-incompatible, or low sugar nectar crops need more colonies Red Delicious apples,
plums, pears
http://freedomtreefarms.com/charts/cherry/
plum pollination chart
* Dr. Richard Fell is the Apiculture Extension Agent at Virginia Tech
Some single ovary early bloomers may not benefit from introduced honey bee colonies
Stone fruits, like peaches & nectarines, require thinning by hand (apples can be chemically thinned)
honey bee on peach
single stigma(leads to ovary)
Bees tend to move down rows—best to interplant pollenizers
Dwarf and semi-dwarf stock may need more colonies dwarf stock=more densely planted
http://www.taranakifarm.com
In this orchard layout, pollenizers are
interplanted
Fell’s “rule of thumb” for farmers to determine if there are adequate bees in orchards
Monitor number of bees in 1 tree on a warm, sunny day 30 seconds OK if 8 to 12 bees(including bumble, mason,and mining bees)
Average at several trees, at various distances from colonies
Osmia (mason bee) on apple
Tricky, huh?
Questions before moving on to pollination research?
Is a global pollinator decline affecting Virginia?
1
Periodic honey bee disease cycle since 1915 approximately 15 to 20 year
cycle (Johnson 2010, Morse and Flottam 1997)
Status of Pollinators in N. America, 2007 (Natural Resource Council of the National Academy of Science)
Baseline data needed
Increasing pollinator dependent crop acres (Aizen 2008)
Primary research objective
halictid bee on blueberry
Investigate the role of native and other non-Apis bees in pollination of entomophilous* crops in southwest Virginia
Available Virginia crop values: apples $37.7 million apple industry value=$235 million (USDA-NASS 2009, VA Apple Board 2010)
tomatoes $88.3 million (USDA-NASS 2006)** cucumbers $4.3 million (USDA-NASS 2006)
watermelons $3.6 million (USDA-NASS 2006)
**Not dependent on bees (except in greenhouses)—bee pollination improves yield & quality in field grown tomatoes.
*Entomophilous derives from Greek for “insects” and “that which is loved.” Unlike wind pollinated plants, entomophilous plants attract insects with nectar, etc.
Study Area in SW Virginia
Undergraduate researcher, Jennifer Kilby, collecting bowl trap specimens
at a caneberry site
Virginia
Blacksburg
Methods: Bee Surveys & Pollen Samples
Survey bees in apple, blueberry, caneberry, & cucurbits• Survey only when weather
conducive to bee activity
• Visual counts & netting at flower at peak flowering time
• Bowl traps (for overall site species richness)
• Pollen load samples (netted at flower)
orchard beeon apple
fluorescent blue bowl trap (with yellow fluorescent & white bowls) in apple orchard—
soap in water breaks surface tension, bees drown
Insect pollinated fruit grown in Virginia
Study crops apple blueberry caneberry • raspberry• blackberry• black raspberry
mining beeon apple
Other insect pollinated fruit grown in Virginia
watermelon, musk melon pear, crab apple, serviceberry, quince (pome fruits) peach, plum, nectarine, apricot (stone fruits) pawpaw strawberry wineberry gooseberry, currant persimmon cranberry, huckleberry elderberry kiwi passion fruit prickly pear honey bee on prickly pear
Rosaceae (rose family) apple & crab apple, pear,
serviceberry, quince ★ caneberry (raspberry,
blackberry, black raspberry, wineberry) ★
peach, cherry, plum, nectarine, apricot★
strawberry
Other fruit families Cucurbitaceae (cucurbit):
watermelon, musk melon ★ Annonaceae (custard-apple):
pawpaw Grossulariaceae: gooseberry,
currant ★ Ebonaceae (ebony): persimmon Caprifoliaceae (honeysuckle):
elderberry Actinidiaceae (Chinese
gooseberry): kiwi Passifloraceae: passion flower Cactaceae (cactus): prickly pear
Ericaceae (heath family) blueberry, cranberry,
huckleberry ★
Crops with Virginia native relatives (shown in BLUE)—what pollinated these before honey bees were introduced?
★ Have more VA relatives not shown
Besides honey bees, what other bees are important crop pollinators in the mid-Atlantic region?
halictid (sweat) bees (various genera)
squash beesPeponapis pruinosaXenoglossa strenua
bumble beesBombus spp.
Osmia photos by T’ai Roulston, http://people.virginia.edu/~thr8z/Bee_Diversity/Blandy_Bee_Diversity.php
mason bees, Osmia spp.mining bees
Andrena spp.
Honey bees are eusocial, bumble bees are primitively eusocial, and most other bees are solitary
Bumble bee queens start a new colony in spring
Female solitary bees make and provision their nests alone
blue orchard bee
(solitary)
brood
honey pots
mining bee (solitary)
Some bees are active in cooler temperatures in spring or earlier in the morning than honey bees
early spring bees bumble bees, Bombus spp. mining bees, Andrena spp. blue orchard bees, Osmia spp. large carpenter bees, Xylocopa spp.
summertime early risers bumble bees, Bombus spp. squash bees, Xenoglossa strenua &Peponapis pruinosa large carpenter bees, Xylocopa spp.
some work later into the evening many, including bumble bees
Many native bees “buzz” pollinate—sonicating flowers improves pollination of crops like blueberry & tomato
Nightshade & heath families (tomato & blueberry, etc)
pollen is only released when sonicated, like sound is released from a tuning fork
pollen
style
stam
en
Percentages of bees visiting crop flowers (2008-2009 study)
★
★ Non-honey bees
Andrenid bees were the most common genus on apple and blueberry (27 species of Andrena in 70 total species on apple)
Andrena barbara was the most common
species on apple (1/4 of all specimens
collected).
vegetation, land cover classes (NLCD), soil (SSURGO) compare data freely available online versus field surveys
Next step: Compare bee species richness with landscape metrics
Management Implications: Practices that support native bee populations like protecting natural areas also benefit honey bees
Some of the best pollen & nectar sources are found in natural areas willow, tulip tree, locust, sourwood, sumac, wingstem,
goldenrod…
bees!!! on wingstem
Management Implications: Remind farmers to avoid chemical use when bees are active or reduce use all together
bumble & honey bees collecting corn pollen
You can’t move native bee nests—avoid spraying during the day Bees collect pollen from many sources (even plants that are wind-pollinated) Fungicides, though not intended for insects, harm bees
Management Implications: Native bees nest in the ground and in vegetation Protect natural areas or create
buffer zones to support bees leave brushy debris unless it may
harbor a pest species provide nesting sites such as
wood blocks, bundles of reed, or bare patches of earth
Many trees are fantastic sources of nectar and pollen stream buffers provide some of
the best habitat
Hedgerows also support other beneficial creatures spiders & predatory wasps
The following links are in a small hand-out--they include info on pollinator habitat & identification FRONT SIDE
Xerces Society: www.xerces.org Farming for Bees: Guidelines for Providing Native Bee Habitat on Farms Using Farm Bill Programs for Pollinator Conservation
Pollinator Partnership: www.pollinator.org Selecting Plants for Pollinators: A Regional Guide for Farmers, Land Managers, and Gardeners in the Southeastern Mixed Forest Province
North American Pollinator Protection Campaign: www.nappc.org Reducing Risk to Pollinators from Pesticides
Bee IdentificationDiscover Life: www.discoverlife.org/mp/20q?search=Apoidea USGS, Sam Droege: www.slideshare.net/sdroege/slideshowsVA, T'ai Roulston: people.virginia.edu/~thr8z/Bee_Diversity/Blandy_Bee _Diversity.phpFlorida (good intro): chiron.valdosta.edu/jbpascar/Intro.htm Bug Guide: bugguide.net
BACK SIDE of HAND-OUT
National Biological Information Infrastructure: pollinators.nbii.gov/portal/community/Communities/Ecological_Topics/Pollinators/Pollinator_Species/Invertebrates/Bees_and_Wasps/
USDA Sustaining Native Bee Habitat For Crop Poll’n plants.usda.gov/pollinators/Agroforestry_Sustaining_Native_Bee_Habitat_for_Crop_Pollination.pdf
SARE’s Managing Alternative Pollinators (for beekeepers, growers, and conservationists) http://www.nraes.org/nra_map.html
Mid-AtlanticVA Fruit Page: http://www.virginiafruit.ento.vt.edu/VAFS-bees.html
Mid-Atlantic Apiculture Research& Extension Consortium: maarec.psu.edu
DE Dept of Agric: dda.delaware.gov/plantind/pollinator.shtml (several terrific guides on native bees, native plants, and farming for bees)
MD DNR: www.dnr.state.md.us/wildlife/wabees.asp (Wild Backyard--Bees)
PA & NJ: www.extension.org/mediawiki/files/1/15/NativeBees2009.pdf
Acknowledgements Richard Fell, Donald Mullins--Co-
Advisors
Douglas Pfeiffer, Lisa Kennedy, & T’ai Roulston—Committee Members
Virginia State government—grant support via the Virginia Cooperative Extension
All the farmers who so generously give access to their farms for this research
Sam Droege, US Geological Survey Bee Guru
Margie Adamson, Sydney Church, Clare Davidoski, & Jennifer Kilby--behind the scenes
VT Entomology Department
Thanks for use of photos from the following web sources http://www.holtanatomical.com/ http://appleparermuseum.com/Images/AppleLongSection
230.jpeg http://comenius.susqu.edu/bi/202/ARCHAEPLASTIDA/VIRI
DIPLANTAE/Flowering%20Plants/judd-photos/Frageria-flower-l-s.jpg
http://www.biologie.uni-hamburg.de/b-online/vascular/ros.htm
http://www.inhs.uiuc.edu/~kenr/Photos/Prunus_flower.jpg http://www.beeculture.com/content/pollination_handbook
/196.gif http://www.katsushikahokusai.org/Plum-Blossom-and-the-
Moon.jpg http://knowledge.allianz.com/nopi_downloads/images/C5_
plum_pox_resistant_plum_genetically_modified_GMO_q.jpg
http://gemini.oscs.montana.edu/~mlavin/b436/labtotal.htm
http://calphotos.berkeley.edu/imgs/128x192/0000_0000/0504/0300.jpeg
http://www.naturehills.com/images/productImages/gooseberry_red_big.jpg
http://en.wikipedia.org/wiki/File:Asimina_triloba3.jpg
Hopefully I haven’t forgotten anyone. If I have or you want to share a better photo with me, please contact me at [email protected]. Other photos are my own or acknowledged within the slides.
Questions?