An online resource based on the award-winning nature guide – maryholland505@gmail.com

Posts tagged “Bumblebees

Fringed Polygala

Fringed Polygala (Polygala paucifolia) looks a bit like a miniature orchid, but it is not — it is in the Milkwort family. The structure of its ¾-inch bright magenta-pink blossoms is well-suited for its bumblebee pollinators.  The bee lands on the pink fringe at the front of the flower and its weight triggers the white “keel” to drop down.  A slit at the keel’s top opens, exposing the reproductive parts of the flower.  Pollen from the stamens is rubbed onto the bee’s hairs while it probes deeply into the base of the flower for nectar, while pollen from a previously visited Fringed Polygala is scraped off onto the stigma, where it needs to be in order for fertilization to take place.

 


Bottle Gentian

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One of our latest flowering plants is the brilliant blue bottle, or closed, gentian (Gentiana andrewsii ).  It is so-called because the tips of its petals come together like the neck of a bottle, protecting the nectar from rain.  The lure of bottle gentian for insects is both the abundance of nectar, as well as its high (40%) sugar content .  Only the strongest of insects, however, are able to struggle their way down into the flower in order to reach the nectaries.  Because of their strength and perseverance, bumblebees are the primary pollinator of bottle gentian.  Once a flower has been visited and its nectar collected, the tips of its petals turn white, signaling other bees that it would be a waste of time and energy to fight their way into the flower. (Yellow lumps are pollen in the bee’s pollen baskets, specialized hairs on the bee’s hind legs.)