Monday, May 18, 2009

Foxtail’s Filters
















Take a close look at meadow foxtail grass’s flower spikes in spring and you’ll find that the youngest have just begun to produce their feathery white stigmas (bottom photo), while more advanced flower spikes are releasing pollen from their dangling stamens (second up from the bottom). Under the microscope the stigmas are revealed at feathery combs of transparent cells whose job is to filter out the airborne pollen (third photo from bottom, x100). Once they’ve trapped a pollen grain it germinates, producing a pollen tube that grows down through the stigma cells (top photo x400), carrying the male cells down to the egg cells in the flower ovary, where they fuse together and begin the process of seed formation. In the top photo you can see the pollen tube emerging from the germinating spherical pollen grain and growing down through a branch of the feathery stigma. There's more on meadow foxtail grass on my other blog at http://cabinetofcuriosities-greenfingers.blogspot.com/

7 comments:

  1. A beautiful world beneath the microscope. Great pictures and interesting info.

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  2. Absolutely amazing sequence of photos. The form and function of grass flowers is clearer to me now. To my naked eye a flowering grass looks confused but at this level I can see how superbly organised it is.

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  3. Hi Les, Thanks for your comment. Even the dreaded couch grass as beautiful flowere when you magnify them a bit.

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  5. Hi Rob., The Botanical Society of the British Isles will shortly be publishing a new guide to grasses - a successor to Hubbard's book that has been in print for half a century.

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  6. Beautiful colours and an informative text, I think I'm hooked now!

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  7. Hi Toffeeapple,it's amazing how the time flies by when you are looking at these things under the microscope. They can be totally engrossing.

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