Fluorescent plant highlight: Dog Fennel

One of the plants we like to point out on our night walks is dog fennel. There’s a clump of it before the batch of pine trees, when we make a right on the path after the garden area. 

Dog fennel in ultraviolet light
The stems glow under UV light.
Dog fennel in white light with bonus fly!
Dog fennel in white light, with bonus fly!

The proper name for this native Florida plant is Eupatorium capillifolium. It’s in the sunflower family, so it’s no surprise it can grow to 6 feet tall, thriving in disturbed areas such as road sides and tilled fields. People also use them as ornamental garden plants. The crushed, inedible leaves are poisonous (hepatic) and have an unpleasant smell, but the oils may be good for soothing sunburns, though we haven’t tried it. The sap also makes the dried plants great for tinder. Lore has it that when they bloom, the first frost is a few weeks away.

See the Wikipedia article linked above for more pictures and info. Also neat is this page about dog fennel and how the scarlet-bodied wasp moth uses the plant toxins in mating. And here’s one more page from Ted Manzer, with good info and nice pictures of the flowers.

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