SEX OF THE FLORAL KIND


 “Written by Claudia Farren with assistance from Bill Boothe of Nature in Focus.” 

Flower pollinators are in decline. The loss of honeybees around the world due to pests, disease, loss of habitat, pesticides, and changing weather patterns has been widely publicized in the last few years. Native bees and other pollinators are also in decline.

Pollinators are a keystone species group; the persistence of a large number of other species depends upon them. As pollinators disappear, the effect on the health and viability of crops and native plant communities can be disastrous. – Xerces Society for Invertebrate Conservation

Pollen allows plants to reproduce by germinating seeds. Wind, humans, and other animals such as bees, butterflies, beetles, moths, and some birds  move pollen within a plant (self-pollination—anther and pistil are from the same plant, but not always from the same flower) or between plants (cross-pollination). Pollinators assist flowering plants while in turn the plants provide food for pollinators and their offspring.

What is Pollen?

Pollen is the male sex particles of plants containing protein, vitamins, steroids, lipids and minerals. Not only does it fertilize flowers but also provides food to the eggs [ovule]. Pollen is disseminated by insects, wind, birds, mammals and water.

RAGWEED POLLEN. 4000x. DARTMOUTH ELECTRON MICROSCOPE FACILITY.  Like most grasses ragweed pollen is dispersed to other ragweed plants by wind.

COLORIZED POLLEN. A RETOUCHED PICTURE FROM DARTMOUTH ELECTRON MICROSCOPE FACILITY.  This photo shows pollen from a variety of common plants: sunflower, lily, primrose, morning glory (the big green one in the middle), and castor bean.

Pollination is the transference of pollen from the anthers of one flower to the stigma of another. In flowering plants the stigma is on the end of the pistil. Once pollen is transferred to the stigma, it travels down the pistil to the ovule where fertilization takes place and seeds are produced.
 
We usually think of insects such as bees and butterflies when we think of pollination, but beetles, hummingbirds, moths, some wasps and flies, and even humans are also important in pollen dispersion.
 
SCARAB BEETLE ON A PRICKLY PEAR CACTUS. Scarab beetles are found throughout the world except for Antarctica. Some common ones are the June bug, the Japanese beetle and the dung beetle. Often brown or black in color, tropical varieties can be iridescent or have a metallic sheen like this one above.
BEETLE ON ASHE MAGNOLIA. Beetles are the largest order of insects with over 350,000 species. This one—on an Ashe magnolia flower—is covered with pollen. The Ashe magnolia grows well in northern Florida. It is a small tree with big flowers and big leaves and has a sweet smell –all excellent attractants to pollinators. 
TWIN-SPOT SKIPPER ON IRIS. Pollinators are attracted through odor, shape, color, and arrangement of the flowers.  
HELICONID BUTTERFLY WITH POLLEN ON PROBOSCIS. In invertebrates, a proboscis is an elongated tubular mouthpart used for piercing or sucking food. During feeding, it is extended to reach the nectar of flowers. When not in use it is coiled under the head.
MONARCH BUTTERFLY ON PURPLE THISTLE. This monarch butterfly is using its proboscis to extract nectar from a thistle. The thistle plant attracts many pollinators including butterflies and hummingbirds.
 
 
HONEYBEE INSIDE BUTTERFLY PEA. Worker honey bees—non-reproductive females—are specialized for pollen and nectar collection. Their hind legs have a pollen basket that can carry large amounts of pollen back to the colony. European honey bees (not native to the U.S.) are social bees, meaning they share the work of building a nest and caring for the offspring. The principle social bees in the Americas are the honey bee and the bumble bee (native).
“About 75 percent of all flowering plants on Earth rely on animals to transfer their pollen, that makes about one in every three bites you eat,” says Kristen Potter, an insect physiologist at Northern Arizona University. “In fact, bees are so important to flowering crops that captive honeybees are sometimes driven from crop to crop at different times of the year to help pollinate plants around the country. However, due to a number of factors such as disease, habitat loss, and pesticides, bee colonies are currently on the decline. Both feral and captive bees have been threatened by these issues, but this is why the native bee species are especially important.”
There are around 4,000 species of native bees in North America, according to the Xerces Society for Invertebrate Conservation. “They have been maintaining flora diversity of North America for thousands to millions of years, and they’re essential to continuing that,” says Rich Hatfield, conservation biologist with the Xerces Society.
 BEE ON BARTRAM’S IXIA. Some of Florida’s native bees are digger bees, sweat bees, plasterer bees, leafcutter bees, bumble bees, cuckoo bees and carpenter bees. Carpenter bees are one of Florida’s major pollinators in wild and urban habitats. Most native bees are unlikely to sting unless disturbed, grabbed, or stepped on
.
NATIVE BEE ON BARTRAM’S IXIA_2, ULTRAVIOLET VIEW. Many flying insects are attracted to ultraviolet light. Some flowers use UV light as a “come hither beacon.”  In this photo a bee is on top of an anther.
DIGGER BEE ON RAYLESS SUNFLOWER. The females rear their young in soil tunnels underground often close to one another, but have no social structure like honeybees. In a “colony” that sometimes number in the hundreds, each female digs out nest cells and collects pollen for her young. Digger bees visit a wide variety of flowers and are important in pollination.

What you can do to help pollinators:

  1. Plant a pollinator garden of native flowering plants with blooms of varying shapes, colors, and sizes. Have something that blooms every month of the year, not just spring and fall.
  2. Plant native host and nectar plants for butterflies from the aster family, pea family, various passion vines, and the milkweed family. Some of Florida’s native milkweed host plants for monarch butterflies include: Asclepias incarnata (swamp milkweed), A. perennis (aquatic milkweed), and A. tuberosa (butterfly weed).
  3. Don’t use pesticides and herbicides.
  4. Provide nesting sites with bundles of hollow plant stems or PVC pipe in a sheltered area of your garden. Make a brush pile in your yard and leave old tree stumps and dead trees on your property. Do remove hazardous snags.
  5. Provide a water source. For butterflies and bees place rocks or sand in a bird-bath bowl that is placed on the ground.
  6. Sponsor or attend a pollinator workshop in your area. Spread the word!

If you would like to get a workshop going in the Panhandle please contact Bill or Marcia Boothe at (850) 643-2583. If you are in another area of Florida contact your local NRCS (National Resources Conservation Service) office at:  http://www.nrcs.usda.gov/wps/portal/nrcs/main/fl/contact/

More valuable information on invertebrate protection is at: http://www.xerces.org. Also an excellent source is the book Planting a Refuge for Wildlife – Creating a Backyard Habitat for Florida’s Native Animals.

Thank you to Bill and Marcia Boothe of Nature in Focus for the photos and also the title of this article. Their website is at http://NatureInFocus.com . A direct link to their butterfly and skipper photos is at http://natureinfocus.com/galleries/butterflies/ .

More pollen photos: http://remf.dartmouth.edu/pollen2/pollen_images_3/index.html

Colorized pollen photos: http://commons.wikimedia.org/wiki/File:Misc_pollen_colorized.jpg

Pollination Graphics: http://www.blog.gurukpo.com/pollination; http://corporate.britannica.com/pollination and http://corporate.britannica.com/termsofuse.html

 

More information on native milkweeds can be found at www.monarchwatch.org/bring-back-the-monarchs/milkweed/milkweed-profiles.

 

Article sources: http://www.coopext.colostate.edu/4DMG/Pests/diggers.htm; http://entnemdept.ufl.edu/creatures/MISC/BEES/euro_honey_bee.htm; http://animals.nationalgeographic.com/animals/bugs/scarab/; http://www.floridata.com/ref/m/magn_mac_ash.cfm ; http://www.britannica.com/EBchecked/topic/467948/pollination

 

 

 

 

 


Comments are closed.