Douglas Justice brings us another photo and write-up from his recent trip to China. He writes:
I have a habit of photographing plants in flower in Botanical Gardens and promising myself that I'll look for the label the next time I go by the plant. Well, I walked by this plant at the South China Botanical Garden in Guangzhou, at least five times. I did do a very quick, cursory look for a label, which I couldn't locate, but I was in a hurry each time I passed it. I suppose I could have asked one of the staff or botanists (the place is rife with scientists), but I didn't. The plant might be Senna bicapsularis (L.) Roxb. (winter senna), but this identification is tentative. The shrub in the photograph is about 2 m tall and wide, the individual flowers some 3 or 4 cm across. I did not see any legumes (fruit).
Senna is a genus of about 250 subtropical and tropical shrubs, sub-shrubs, lianas and herbs. Few are cold hardy enough to cultivate in temperate conditions, but Michael Dirr mentions in his Trees and Shrubs for Warm Climates (Timber Press) that S. bicapsularis overwinters (but dies to the ground in the cold) in his Georgia garden. Locally, Senna didymobotrya (popcorn plant) was a popular summer container plant for a few years. It is an attractive African species that requires frost-free conditions. It smells of buttered popcorn (really).
I love the mustachioed blossoms and the golden line around each lovely leaf. What beauty !
The flowers are truly lovely. So are the leaves. The plant is graceful. But the best part is the seed pod, which is not at all like a legume, more like a tan balloon.
I would love to see the lugumes!
Two questions:
Are the curly mustaches anthers?
Consequently, any idea what the pollinator may be?
Beautiful. I understand that the bright colours in flowers help attract pollinators. But what is the significance of the number and shape of the petals in flowers? Why do they vary? I am especially interested in the number part.
Thanks
What a facinating little structure! Love it's specilized design...while the pollinator is getting the nectar the polyps(?) are rubbing their spores on the body...how neat!
I'm no Fabaceae flower expert, but I think I can explain what we're looking at. There are 5 petals. In the classic pea flower (Subfamily Faboideae), the two lower petals are partially fused to form a "keel" that encloses the stamens and style. Here (Subfamily Caesalpinioideae), the petals are all "free" and the reproductive bits (other than the ovary) are exposed. The long, curved, green wiry structure in the centre of the flower is the style, which is the upper extension of the ovary. The ovary (which will become a legume if pollinated) is hidden behind the petals. The stigma (pollen receptive surface) is on the inside of the curved tip of the style. There are 10 stamens in 2 series, 3 curved ones and 7 short ones. I think we can safely assume the pollinators are bees.
bright happy interesting yellow flower
sunshine on sunday morn thank you
To answer Justin's question, yes the "mustache" is made by the anthers. What a very cool plant! I wonder whether it would do well in a container. It is too cold in winter here in the North Carolina mountains, but I think it would be worth the trouble to over winter indoors.
What a neat plant!
I've been trying to practice my plant ident skills with these pics by not reading the family label until I've looked at the picture - this one really got me because my instinct was telling me it was a Fabaceae, but the flowers didn't fit - guess I should go with my gut next time!
Ahhh... yet another reason to live in the subtropics.