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Tree Flowers (and fruits) 

Norway maple

Norway maple, Acer platanoides is a hardy European tree widely planted as a street and lawn tree. It is increasingly unpopular because of it invasive tendencies, being seen more and more in woodlands where it doesn't belong. Norway maple flowers profusely in mid-spring. Leaves and flowers emerge simultaneously. Entire trees look like giant yellow pom-poms.  

Norway maple

Norway maple. April 22, 2008, Grant Cemetery, Columbus Ohio.

Norway maple flowers, colorful and conspicuous, are visited by nectar-seeking bees.

bee visits Norway maple

Honeybee foraging Norway maple flowers. April 22, 2008. Grant Cemetery, Columbus, Ohio.

This species is variously reported as monoecious, i.e., producing unisexual flower with both sexes on the same tree, or dioecious (separate male and female individuals). Examining several trees flowering over a 2-week period only made things more confusing. Flowers with a well-developed pistil also bear stamens, but they are distinctly shorter than the stamens of obviously male flowers that lack a functional pistil.  And it seemed that some trees that produced female flowers early in the blooming period shifted over to solely staminate ones later in the season (or was it the other way around?). This aspect of the species -- its "breeding system" --requires closer monitoring. 

Norway maple staminate flowers

Staminate (male) flowers of Norway maple. April 22, 2008, Union Cemetery, Columbus, OH.   

Norway maple staminate

Pistillate flowers of Norway maple. April 22, 2008, Grant Cemetery, Columbus, OH.

Norway maple pistillate

"Studio" photo of pistillate Norway maple flower gathered
April 25, 2008 at Union Cemetery, Columbus, OH.

Norway maple young fruits

Norway maple young fruits. May 8, 2008. Union Cemetery, Columbus, Ohio.

After a period of fast growth during which the maple fruits (samaras) acheive full size, they remain on the tree all summer long with little apparent change in appearance.

Norway maple fruits

Norway maple fruits. June 5, 2008. Union Cemetery, Columbus, Ohio.

Norway maple samaras

Noway maple fruit. June 11, 2008. Union Cemetery, Columbus, OH.

It's not until October that the samaras finally fly off the tree. Many lay on the ground beneath, "littering" the streets. Nice.

Norway maple samaras on road

Norway maple samaras on the road beneath a tree.
October 22, 2008. Union Cemetery, Columbus, Ohio.