Licorice Fern

It's About Time - December 2012

Licorice Fern frond tip with one spore case cluster enlarged

They’re baaack! The mosquito ferns have reappeared in the ponds on the east side of Delta Highway. They have been inconspicuous for three years, a normal population fluctuation. We recognize them by the dark, reddish-brown surface mat on the ponds. Duckweed stays green all winter but the mosquito ferns get color in the fall. That they are still reddish brown and not shocking purple tells us that by the beginning of December we still haven’t had a hard freeze.

Jupiter continues bright in the sky this month, rising not long after sunset. It will be a sparkling ornament hugging the nearly full moon on Christmas Day. Orion is back in the evening sky when I take our dog out for our bedtime stroll. Orion and the Pleiades are old friends returning from a six month voyage to the other side of the world. If the sky is clear before dawn on the 14th, the Geminids could be the best meteor shower of the year.

The newly uncurled fronds of licorice ferns on tree branches are wonderful to behold. The bright, spring green is magical at a time of the year when most terrestrial herbaceous plants are withered and dormant. These have a reverse cycle from the ferns of the forest floor. I have counted how many sporangium clusters are on a typical leaf, how many spore cases in a typical cluster, and multiplied that by 64, the number of spores in a sporangium. Average production is four to five million spores per frond!