Sunflowers, the late summer feast

Sunflowers, the late summer feast: Click for a larger view of the sunflower garden. Image courtesy and copyright Jim Cane
Stand of ornamental sunflowers
in Cache Valley
Image courtesy and Copyright Jim Cane

Click for a larger view. Image courtesy and copyright Jim CaneHoney bee foraging at sunflower
Image courtesy and Copyright Jim Cane


Click for a larger view. Image courtesy and copyright Jim CaneMale Melissodes bees and a skipper
butterfly sleeping on a sunflower at dusk
Image Courtesy and Copyright Jim Cane

Now, in late summer, the sunny golden blooms of sunflowers adorn gardens, roadsides and wild places across much of the United States. Utah is home to five sunflower species, four of them annuals. You are most likely to see Helianthus annuus, the aptly named “common sunflower”. Early domestication of common sunflower by Plains Indians led to the major oilseed crop that the world enjoys today.

Humans are not the only species seated at the sunflower dining table, however. The grub of one specialist weevil bores in sunflower stalks; as do larvae of 2 long-horned beetles. Another weevil hollows out the seeds. A third decapitates the flowerhead before ovipositing. One moth’s caterpillar gnaws the roots; several cutworm species topple seedling sunflowers, and several more kinds of butterfly caterpillars skeletonize sunflower leaves. In your garden, though, sunflowers generally escape pestilence. Chickadees and both American and Lesser Goldfinches cling to the ripe seed heads to pluck out the nutritious seeds. Listen for the plaintive call of the Lesser Goldfinch which is very distinctive.

[Lesser Goldfinch, Audio recording courtesy Kevin Colver, 7loons.com: Songbirds of the Southwest Canyon Country]

All those sunflower seeds are the direct result of pollination by bees. In the American West, more than 200 species of native bees visit sunflowers for nectar or pollen, a remarkably large fauna for any flower. None is more charming than the male of the bee genus Melissodes. They are discernible by their extra long antennae. Melissodes males dart among sunflowers all day long, seeking willing mates. Come sunset, the males bed down on the flower heads to snooze. They become drowsy enough to pet with your fingertip, and being males, have no sting. So if you have sunflowers at hand, chances are you have Melissodes bees around too. Look over your sunflowers this evening, and you may be lucky enough to find these dozing bachelor bees with their extra long antennae.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Audio: Courtesy Kevin J. Colver, 7loons.com and On Amazon.com
Photos: Courtesy and Copyright Jim Cane
Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

LeBuhn, Gretchen, Greenleaf, Sarah, Cohen, David, The Great Sunflower Project, Department of Biology, San Francisco State University, http://www.greatsunflower.org/

Charlet, Larry D., Brewer, Gary J., Sunflower Insect Pest Management in North America, Radcliff’s IPM World Textbook, University of Minnesota, http://ipmworld.umn.edu/chapters/charlet2.htm

The Native Bees of Utah

Male Melissodes Bees
Sleeping on Sunflower
Courtesy and
Copyright © 2010 Jim Cane

The industry and cooperation of honeybees have inspired many a philosopher and society, including the Mormons who settled along the Wasatch front. The hive, or more specifically a skep, was later chosen as the emblem for the new state of Utah. But the honeybee, like it’s pioneer admirers, is a recent European immigrant, brought over for the wax and honey that colonies produce.

Utah did not lack for pollinators, however, prior to European settlement. More than 1000 species of native bees inhabit Utah, with several hundred species in any given county. A few of these bees — bumblebees and sweat bees — are social. They produce annual colonies headed by a queen. However, the vast majority of our bees are not social. For these, each adult female makes her own nest with no help from her sisters or mate.

Most solitary bee species nest underground; others use old beetle burrows in deadwood. The resident female subdivides her tunnel into bee-sized cavities. Each cavity receives a cache of pollen moistened with nectar and a single egg. There each grub-like larva will feed and develop in solitude. Most solitary bees will spend the winter here in their natal home.

Bombus griseocollis Queen
Foraging on Hedysarum
Courtesy and
Copyright © 2008 Jamie Strange

Native bees pollinate many of Utah’s wildflowers, doing so inadvertently as they busily gather pollen for their progeny. Many solitary bee species are taxonomic specialists, focusing all of their pollen foraging efforts on one or a few related genera of flowering plants. Some common hosts for specialist bees in Utah include squashes, sunflowers, globemallows and penstemons. Sweet honey does not result from the labors of solitary bees, but fruits and seeds do. The industry of Utah’s native bees merits our attention and admiration.

This is Linda Kervin for Bridgerland Audubon Society.

Credits:

Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

USDA-ARS Pollinating Insects – Biology, Management and Systematics Laboratory, http://www.ars.usda.gov/main/site_main.htm?modecode=54-28-05-00

Crop domestication facilitated rapid geographical expansion of a specialist pollinator, the squash bee Peponapis pruinosa, Margarita M. López-Uribe, James H. Cane, Robert L. Minckley, Bryan N. Danforth
Proc. R. Soc. B 2016 283 20160443; DOI: 10.1098/rspb.2016.0443. Published 22 June 2016http://rspb.royalsocietypublishing.org/content/283/1833/20160443.abstract

Pollinating Fruit Trees with Blue Orchard Bees

Audio:  mp3 Listen to WildAboutUtah

Blue Orchard Bee
Copyright Jim Cane

Apricots, plums, apples, cherries, and pears all need bees to pollinate their flowers. Traditionally, we’ve used the European honey bee, but now we know how to pollinate our fruit trees using a steely blue native bee, the blue orchard bee (Osmia lignaria). These wild bees fly nationwide.

In Utah, they live in foothill and lower montane habitats. Blue orchard bees are not social; every female is fertile and tends to her own tiny nest. Adults are the size of a chunky honeybee and are active for only 3-4 weeks in the spring. These bees naturally nest in the tunnels chewed by large wood-boring beetles in tree trunks. Each female partitions her tunnel into a series of tiny bee-sized rooms. Each room is stocked with a pea-sized provision of pollen moistened with nectar, followed by a single egg. Nest cells are partitioned, and ultimately capped, with mud, hence their other common name: “mason bees”.

Blue Orchard Bee eggs
on pollen provision mass
in nest
Copyright Jim Cane

You can have your own backyard population of blue orchard bees. An easy way to begin uses a short fat log that is seasoned and dry. Take a 5/16 bit and drill 20 or more holes radially 5 to 6 inches deep. Stand the log on end, facing the holes towards the southeast.

On cold mornings, nesting females bask in the sun before taking flight. If bees colonize your log, you will see the steely blue females busily coming and going all day long during fruit tree bloom. They tote their loads of dry yellow pollen in a brush of hair beneath the abdomen. Unloading that pollen at the nest requires some charming acrobatics that are well worth watching. While collecting pollen, female blue orchard bees pollinate your trees with hundreds of fruits resulting from each bee’s lifetime of work. Successive generations will nest for you every spring, but you’ll want to switch to replaceable nesting materials to prevent the accumulation of pathogens and parasites.

Details and links can be found at our Wild About Utah website.

This is Linda Kervin for Bridgerland Audubon Society.
Credits:

Photos: Courtesy & Copyright Jim Cane

Text: Jim Cane, Bridgerland Audubon Society
Additional Reading:

Drill Log with 5/16 holes
5 to 6 inches deep
Copyright Jim Cane

Resources:

http://www.sare.org/publications/bob.htm

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

http://www.pollinatorparadise.com/Binderboards/Hornfaced_Bees.htm

A Colonized log
Copyright Jim Cane

Utah’s wool-gathering bees

Audio:  mp3 Listen to WildAboutUtah

Fluffy contents of the reed nest
of a carder bee
Courtesy & Copyright Jim Cane

Do you grow the ornamental plants called “lamb’s ears” or rose campion in your flower gardens? These plants produce dense mats of buttery soft woolly leaves. That leaf fuzz is avidly sought by so-called “carder bees” of the genus Anthidium. In textiles, carding is the mechanical process of combing through the fibers of cotton or wool to align them before spinning. The female carder bee has multi-toothed mandibles that she uses to shave the leaf hairs, gathering the fluff into a ball to bring back to her nest.

Lamb’s ear leaf shaved of some of its hairs
Courtesy & Copyright Jim Cane

Carder bees nest solitarily in aboveground cavities, typically an old beetle burrow in deadwood. Each female lines her tunnel with the carded plant hairs. Onto this fluffy pillow she assembles a provision of pollen mixed with nectar, which constitutes the food mass soon to be eaten by her progeny, one provision per larva.

Carder bees are stout, round, relatively hairless bees marked in black and yellow. We have several species, the largest being a European escapee that is associated with lamb’s ears. The female’s nesting biology is distinctive enough, but it is the male’s behavior that you will notice first.

Male carder bee at lavender flower
Courtesy & Copyright Jim Cane

Male carder bees are aggressive, territorial suitors. They spend all day in flight, tirelessly patrolling lamb’s ears and garden flowers, particularly culinary sage and Russian sage. Males dart at all carder bees of either gender, as well as other like-sized bees. They pounce upon and wrestle these unsuspecting individuals to the ground. If it is a female of their species, they will endeavor to mate with her. Such is the brazen courtship of male carder bees. Look now for these wool gathering bees in your gardens before summer bids us farewell.

This is Linda Kervin for Bridgerland Audubon Society.
Credits:

Photos: Courtesy & Copyright Jim Cane

Text: Jim Cane, Bridgerland Audubon Society

Additional Reading:

Anthidium_manicatum, BugGuide, BugGuide.net, http://bugguide.net/node/view/7744

Anthidium_manicatum, Discover Life, Polistes Foundation, http://www.discoverlife.org/mp/20q?search=Anthidium+manicatum

Wool Carder Bee (Anthidium manicatum), Solitarybee.com, Paul Betts, http://solitarybee.com/blog/2010/08/wool-carder-bee-anthidium-manicatum/