Another Brooklyn blogger reports:
One crisis I've been tasked with dealing with [from a co-op board meeting] is one of our ginkgo trees in the front of our building has apparently decided to change its sex - from male to female; or at least one branch of it has done so.
- Thoughts While Looking Up, Ink Lake, 2009-11-17
Ginkgo biloba is a dioecious species, with male and female flowers on different plants (usually). The fruit of Ginkgos, which arise only from the flowers of female plants, is notoriously messy and smelly, hence the co-op's concern. We had a close encounter with some on the Sustainable Flatbush Street Tree Walking Tour a few weeks ago.
The gender of dioecious flowering plants can't be determined until they flower; male and female plants must be selected and copied through vegetative propagation techniques as cultivars, i.e.: clones. Hollies, Ilex, are also dioecious, and gardeners who want berries on their Hollies must purchase known-female cultivars and ensure that compatible males are close enough for pollination.
Flowers on the female cultivar of Ilex verticillata, Winterberry, in my backyard native plant garden. The sticky stigma, which receives the pollen from the flowers of the nearby male plant, is clearly visible in the center of the flower.
The ability of dioecious plants to change gender has been observed before, though it's unusual. The mechanisms by which individual plants "choose" their gender remains unknown; the accelerating capabilities of genetic technology are likely to change this. If any reader has some good references, please share them in a comment below.
[bit.ly]
Here's a recent paper I found about sex determination in ginkgo: http://www.bio.uaic.ro/publicatii/anale_biochimie/2006_VII/2006_GBM_18_Ll.pdf
ReplyDeleteBasically, they've gotten close to identifying a gene that they think makes the trees male -- but they don't even mention the occasional sex change trick ginkgos play! Maybe the sex change is caused by a mutation in the male gene?
The ginkgo is one of my favorite trees. I especially like the tree in the fall when its leaves will drop all at once.
ReplyDeleteold ginkgo - http://www.humanflowerproject.com/index.php/weblog/comments/gethsemanis_gingko_tree/
manipulating sex of trees - http://humanflowerproject.com/index.php/weblog/comments/girl_trees_of_beijing/
-- localecology.org
The nut within ginkgo fruit is edible. If you look here on my web site http://www.bellewood-gardens.com click on Diary, go to November and use the hot link to Ginkgo at the New York Botanical Garden there are images of gnkgo in "the other garden" and information on how to clean the fruit, plus a recipe for a Japanese savory custard.
ReplyDeleteEnjoy.
Judy
I had a delicious "chawan-mushi" just yesterday at Hasaki. In addition to morsels of shrimp, chicken and shitake, the egg custard had the requisite two gingkos. One of my fave Japanese dishes in the wintertime
ReplyDeleteLove the ginkgo photo. We have one and it put down those luscious yellow leaves this fall as well.
ReplyDelete