Help ID this tree

Hi everyone,

I just saw this picture and was curious to know what plant it is. Never seen anything like it. The only info I got is that it is a tree common along the Colorado River.

http://www.flickr.com/photos/ivoryblushroses/4542006849/sizes/o/

I am from South America, so I'm not familiar with North American plants.

Thanks!

Candida

 

It looks like the flowers of Acer negundo. Common name Boxelder.

http://images.google.co.uk/imgres?i...-gb:IE-SearchBox&rlz=1I7SUNA_en-GB&tbs=isch:1

 

Definitely Acer negundo, also called Manitoba Maple. It's a weedy species even in its natural range.

 

Native range extends as far south as Guatemala.

 

Thank you, guys!

So those are the male flowers... really intriguing and beautiful. The flower adaptations to pollination always amazes me. They almost look like the hanging stamens of many grasses.

Thanks, again!

 

That's actually pretty logical when you consider that both this tree and most grasses depend on the wind for pollination.

 

Exactly, lorax ... and a different strategy of other wind pollinated species, such as Salix and Betula , with long flexible catkins.

Instead of a long drooping central stem bearing flowers, why not make long drooping flowers? :)

 

I think the difference there is the fundamental one between Monocots and Dicots. For the Monocots (like the grasses), there really isn't any other option than to create a drooping central stem bearing the flowers, since branching in the normal sense is pretty much unheard of in that division (bamboos being the sort-of exception). Meanwhile, the Dicots, which are free to branch, can create both long-stamened, drooping flowers (like Theobroma cacao does) and drooping central stems of flowers (like Betula and Salix do). Whence the grand diversity of the plant kingdom!

However, I'd also suspect that the drooping central stem with flowers is more efficient for the plant, energy-wise, and poses less of a problem with the loss of flowers or vital flower parts. A stem or rachis or raceme is sturdier than a simple floral peduncle, and can therefore stand up to more wind.

 

Agave americana? Puya raimondii?

 

Upright central stems bearing flowers as well. My bad. However, since I was referring to the monocots that rely on the wind for pollination..... For the Agaves and Puyas, I happen to know the pollinators are hummingbirds; P. raimondii in particular relies on the Andean Hillstar.

 

lorax, I agree with your suspicion that the drooping central stem with flowers seems to be more efficient. However, it could be that those peduncles are not less sturdier than an inflorescence rachis. And when you think about those stamens in inflorescences of wind pollinated monocots, hanging out with their long filaments... they must be sturdy enough, otherwise it also represents a vital part which can be lost. Gee! This discussion can go on and on! lol!

Thank you guys. All these info are of great value. I really appreciate your time and efforts.

 

I think it all comes down to the intensity and frequency of the wind in the places where these plants grow naturally. Plants from tornado-prone areas would naturally produce sturdier inflorescences than those that are from areas that only experience a light but constant breeze.