s39_pp - Corn Mazes America

The blue orchard bee: A native managed pollinator

Christelle Guédot Department of Entomology

Most important insect pollinators: Bees 1. Feed on nectar and pollen 2. Pollen collecting structures (scopa, corbicula) 3. Display floral constancy (strong tendency to visit flowers of the same type on a single foraging trip): important for pollination because minimizes pollen wastage and stigma clogging with pollen from other species Andrena

Osmia bicornis

Jeremy Early

Wikimedia Commons http://www.naturesdesktop.com/images/wallpapers/1600x120 0/insects/bee-collecting-pollen.jpg

John B. Pascarella, Sam Houston State University

pollinator.info

Why are bees important? Whole foods and Xerces Society "Share the Buzz" campaign (2013)

Bees • At least 25,000 known species of bees • Social vs. solitary, 90% being solitary

• ~4,500 of solitary spp. in North America • Wisconsin: ~390 spp. (Wolf and Ascher, 2008)

Stephen Buchmann

Smallest North American bee (Perdita minima) on largest female carpenter bee

Native Exotic

T'ai Roulston, University of Virginia

Bees: distinguishing characteristics Bees Robust Hairy Flat rear legs Feed on nectar and pollen

vs.

mommammia Flickr

Wasps Slender Smooth Slender legs Predators

James Cane

Life cycle of a solitary bee

Mining bee (Andrena sp.): a year in its underground nest as egg, larva, and pupa before emerging to spend a few weeks as an adult.

Photos: Dennis Briggs

Ground-nesting solitary bees ~70% of native bee species nest underground • Resemble ant-nests from above ground • Nests may be as deep as 3’

Photos: Eric Mader, Matthew Shepherd, Dennis Briggs

Cavity-nesting solitary bees ~30% of native species nest in cavities •Nest in hollow plant stems, old beetle borer holes, man-made cavities •Nest have tunnel partitions constructed of mud, leaf pieces, or sawdust •Artificially managed for some crops

Photos: Edward Ross, Darrin O’Brien, Matthew Shepherd

Bees for fruit tree pollination Impediments to bee pollination on fruit trees

- Early season; bad weather - Short flowering period: 2-3 weeks - Flowers receptive only few days Christelle Guédot, UW-Madison

- Cool temperatures slow pollen germination ovules might degenerate before fertilized - Incompatibility: bees must move between inter-compatible cultivars in different rows

Flower morphology ♀ organ ♂ organ

≡ Pistil

Apple pollination • Pollinate king blossoms (first to open, produces larger fruit) • Pollinate blossoms with large amount of compatible pollen for high number of seeds, which relates to fruit size and shape • Size of fruit affected by number fruit produced; thinning might be required

http://appleharvester.blogspot.com/2011/05/king-blossom.html Christelle Guédot, UW-Madison

The blue orchard bee • Osmia lignaria, a native

• Solitary but gregarious • Nest in pre-existing cavities • Only females provision nest

• Collect nectar and pollen for provision • Collect mud for nesting material Back

Front Egg

Cell1 Mud partitions

Provision

The blue orchard bee

Females

Male Female 0.4 - 0.6” long

Prepupa instar larva inside coccon

5th

White pupa

Black pupa

Adult

Life cycle of blue orchard bee Eggs hatch, larvae grow into pupae

Late March

April - May

June

July - Aug

Sept - March Dormant adults

Identifying females vs. males Males smaller than more robust females

Males have longer, more slender antennae

Males do not have scopa, females do

Males have more facial hair

http://seabrookeleckie.com/

Life history • Fecundity: 10 - 20 eggs / nesting female (2.5 - 6 ♀ eggs) • Longevity adult females: ~20 days • Females build ~ 2-4 nests in lifetime • Emergence:- males emerge 24-48 hrs after warming - females emerge 1-3 days later

Why the blue orchard bee? discoverlife.org: Osmia lignaria distribution

• Native • Commercial use in 1970’s • Forages in cool weather > 54°F

Designed by The Polistes Corporation

• Visits many tree species: almonds, apple, pear, cherry, apricot,…

Why the blue orchard bee? Foraging behavior and pollination effectiveness % Stigma contact

Christelle Guédot, UW-Madison

http://www.ars.usda.gov/Research/docs.htm ?docid=18333

Almond

Apple

Pear

Osmia

98.7

97.7

98.7

Apis (P)

67.3

-

51.8

Apis (N)

39.5

32.7

19.0

Why the blue orchard bee? • Blue orchard bees readily move from tree to tree and row to row • Facilitate cross-pollination, rather than pollination within a tree or within a cultivar • Preference for fruit tree pollen: 85-100%

Dandelion

http://www.swcolorado wildflowers.com

Golden currant

Why the blue orchard bee? Active at low light levels and low temperatures

• 33+ hours foraging in 5 days • 15+ hours by honey bees Usual foraging range: 300-600 ft Max. foraging range: 1,300 ft Homing ability: 4,000 ft

Apple yield with blue orchard bee Commercial Apple Orchard, Utah Apple yield (bushel)

1977 + 1978 Honey Bee

1979 + 1980 Blue orchard bee

McIntosh

4380

5186

Red Delicious

986

3248

Golden Delicious

204

288

Jonathan

430

417

Rome

184

307

Total

6184

9446

Apple Variety

53% increase

Why the blue orchard bee? Commercial cherry orchard, Utah Year

Pollinator

Cherry yield (Kg)

♀ BOB increase

1992

Honeybee

-

-

1993

Honeybee

3,040

-

1994

Honeybee

5,545

-

1995

Honeybee

4,820

-

1996

Honeybee

3,695

-

1997

Honeybee

-

-

1998

Blue orchard bee

14,875

5.44

1999

Blue orchard bee

4,150*

2.17

2000

Blue orchard bee

16,935

4.21

2001

Blue orchard bee

4,415**

1.03

2002

Blue orchard bee

-*

2.45

2003

Blue orchard bee

6,680***

0.62

* Freezing event; ** missed timing on BOB release; ***high bee predation by birds

Number of females Optimal number of nesting females for adequate pollination Blue orchard bee

Almond

Apple

# nesting females/acre

300

250

3

2.5

# females/tree

In comparison, need 1 - 2.5 honeybee hives / acre (typically 30,000 - 50,000 workers / hive)

Pollination efficiency Flower efficiency and fidelity • 75 flowers per “load” of pollen and nectar • 15-35 loads per provision Christelle Guédot, UW-Madison

• 75 X 25 (avg.) = 1,875 flower visits per provision • Female provisions 7 – 12 cells in her life • A single female visits 10,000-20,000 flowers in her lifetime! • Remember: 85-100% orchard flower pollen

How to manage the blue orchard bee What do you need to have blue orchard bees in your orchard? • Care, attention, enthusiasm • Bee stock • Nesting equipment • Appropriate storage facility • Proper handling http://www.sare.org/LearningCenter/Books/How-to-Manage-the-BlueOrchard-Bee

Where to obtain bees and materials

Nesting shelters

• Attach shelter on tree or fence post • Orient SE for longer foraging activity (and more attractive to nesting females) James Cane, USDA ARS

Shelter with wooden blocks and chicken wire

Nesting blocks Prefer wood blocks Paper straws in cavities help for handling and storage

Reeds

Wafer boards

Nesting cavities - 19/64” (7.5 mm) hole diameter - 6” (15 cm) long - Plan on 3-5 nesting cavities per female released

Nesting material • Mud is a vital nesting material • Clayey mud, not sand or loam • Need safe place for gathering mud, within 20-50ft. of nest

A typical BOB season Example for Northern Utah 1) March/April About two weeks prior to expected bloom: • Check flower development • Check weather forecast

A typical BOB season 2) March/April • • •

Set up nesting materials and mud sources Incubate bees at 72-76°F (22-25°C) Emerged bees can be held at 37-41ºF for ~a week

A typical BOB season 3) March/April Release BOB population (200-300 females + 400-600 males per acre for full pollination in almonds, cherries, apples, and pears)

A typical BOB season 4) May/June Retrieve nesting materials • Move nests to summer storage (avoid excessive heat, direct sun) • Take measures to avoid parasitism Adult female chalcid wasp, Monodontomerus

Blue orchard bee nests by black light trap Note large numbers of drowned Monodontomerus in tray Adult female chalcid wasp, Melittobia chalybii

A typical BOB season 5) June through August

Monitor development with monthly development checks • Select 10 male cocoons from different nests

A typical BOB season 6) Mid/late September Move nests to winter storage (refrigerator) • Check small sample of females from different nests to be sure that all adults • Best if population held for 1 week at 55°F before being placed in artificial wintering at 39°F • Require minimum of 3 months wintering: adults go dormant (diapause)

A typical BOB season 7) November/December • • •

Quantify population Remove parasites and diseased bees (now dead) Prepare nesting materials for the following season

Hairy-fingered pollen mite, Chaetodactylus krombeini

Chalkbrood fungus

Recently emerged male covered with migratory nymphs of hairy-fingered mite

Summary

• Blue orchard bees are superb orchard pollinators • BOBs can be used alone or along with honey bees • Easy management • Bees are safe

Spray guide

Acknowledgements

• Jordi Bosch • Theresa Pitts-Singer • William P. Kemp • USDA-ARS Beelab