poinsettia are not poisonousPosted: December 23, 2010
I’ve been admiring the uniqueness of poinsettia flowers, and wanted to share some botanical Christmas cheer.
Poinsettias have been associated with Christmas since the 16th century: the leaf shape is reminiscent of the star of Bethlehem, and the red crown reminds us of our Savior’s blood sacrifice.
Euphorbia pulcherrima flowers are a bit unexpected. To find the flowers, you must look past the large red showy things, which are technically modified leaves called bracts. Bring your nose in close, so you can smell its earthiness. At the heart of the little saplings (which, if given the opportunity, will grow into a full-sized tree…which you can see later in this post) you’ll see a cluster of green bulbous heads, each with a tuft of red spikes topped with yellow powder. Each of these radical hair-dos is actually a full bouquet of flowers. The botanical term for this type of flower grouping is cyathia, which is Greek for cup. Each staminous spike projecting from the cup is really a single flower with it’s own ovary and stamen. That dusting of yellow powder is pollen, akin to tiny plant sperm.
In my photo, one of the lower-right cyathias has one mature flower projecting out of it. Its ovary has grown too large to remain inside the floral cup. My favorite morphological features of this plant are the luscious yellow lips, oozing with honey. These are nectar glands. Usually individual flowers have their own nectar gland, but in the case of poinsettia the whole grouping of flowers shares the pot of gold with the lucky pollinator.
I spent some mindlessly mesmerizing time at work pasting pins onto business cards. The little glue dots reminded me of poinsettia nectar.
Another thing the glue dots and the poinsettia have in common is that they are both relatively non-toxic. I admit that I’ve more than once joined in the rumor that these Christmas plants are highly poisonous, but some recent research reveals it’s just not true. A study of 849,575 plant exposures by the American Journal of Emergency Medicine showed no know fatalities from the plant. Another study predicted a 50 pound child would have to ingest 500 bracts before any toxicity would result. It is true, however, that the plant has a milky latex-like sap that might cause some mild skin irritation. So, if you have an allergy to latex you should probably fore-go the poinsettia rub-down this year. The toxicity misconception probably arose because poinsettias belong to the genus Euphorbia, which contains some truly toxic species.
Even though I don’t have a latex allergy, I likely won’t be serving up poinsettia saplings for Christmas dinner. I just want to prevent anyone from freaking out if they catch a child or pet gnawing on a bract.
Cheers to Euphorbia pulcherrima, and Merry Christmas to you.