Wednesday, 1 November 2006

Puffy Land

Puffy Land

This picture was taken at Melbourne University. I had went there during the holidays to borrow books and video for my English for Academic Purposes (EAP) presentation of fossil fuels. It was spring and the trees were spitting these feathery seeds all over the South Lawn. I decided that it was too rare to miss out such an opportunity.

One of the important functions of seeds and fruits is dispersal; a mechanism to establish the embryo-bearing seeds in a suitable place away from their parental plants. There are 3 main mechanisms for seed and fruit dispersal: (1) Hitchhiking on animals, (2) Drifting in ocean or fresh water, and (3) Floating in the wind.

Parachutes include seeds or achenes (one-seeded fruits) with an elevated, umbrella-like crown of intricately-branched hairs at the top, often produced in globose heads or puff-like clusters. The slightest gust of wind catches the elaborate crown of plumose hairs, raising and propelling the seed into the air like a parachute. This is the classic mechanism of dispersal for the Eurasian dandelion (Taraxacum officinale) and includes numerous weedy and native members of the Sunflower Family (Asteraceae). A giant Eurasian version of the dandelion called salsify or goat's beard (Tragopogon dubius), is one of the most successful wind-travelers in North America. Its seeds have literally blown across mountain ranges, colonizing vast fields of open land in the western United States. Three weedy species of salsify (T. dubius, T. pratensis and T. porrifolius) have been introduced into the western United States, 2 with yellow dandelion-type flowers and one with purple flowers. The latter, purple-flowered species (T. porrifolius) has a large, edible tap root with a flavor resembling oysters, hence the name "oyster plant."



Jon said...

Shit, didnt know that can find such nice pictures in melb uni
actually not so... ur autumn pic of uni also damn cool

De Foto said...

Haha.. Thank you jon. just notice more of the unoticed side of Mel U. haha. I like the puffy land too. haha.