Ever wonder why red and green are the colors of Christmas?
Back when Christmas was mainly religious, red and green represented the Holly Tree, which Christians considered symbolic of the crown of thorns worn by Jesus (others considered it a symbol of fertility, or a charm to ward off witches and bad luck).
European holly, Ilex aquifolium (source).
The Holly Tree of Christmas, Ilex aquifolium, is restricted to Europe. In Wyoming we have no hollies at all, and the nearest members of the genus Ilex grow in the southeastern United States. So we have to be creative in making homegrown botanical Christmas cards. This year I chose rich red paintbrush bracts and pale blue-green sagebrush leaves—symbolic of the sagebrush steppe that covers so much of the state.
Sagebrush steppe northwest of Daniel, Wyoming. Photo by Matt Lavin.
Photo courtesy US Fish & Wildlife Service.
Red “flowers” of paintbrush (Castilleja) are actually bracts; flowers are yellow (click image to view).
Finely-hairy drought-resistant leaves of sagebrush (Artemisia tridentata) contain camphor and other volatile oils, suggesting true sage when crushed (source).
This plant pair wasn’t just a lucky find. Paintbrush often grows next to a sagebrush, its roots penetrating the sagebrush roots to siphon off water and nutrients. Some might object to a Christmas card featuring a parasite. But wait ... the relationship may prove to be mutually beneficial.Paintbrush is only partially parasitic; it can also photosynthesize (note green leaves). Sagebrush doesn’t appear to suffer much from this relationship unless conditions are harsh (especially drought). And in some cases, paintbrush provides benefits, like increasing nitrogen availability in poor soils. Finally, given the rate at which mutually-beneficialand even mandatory symbioses are being discovered—possibly the norm rather than the exception—further research may force us to rethink our story about paintbrush and sagebrush. They may represent the sharing spirit of Christmas after all.
