Oak Mistletoe
Photo @1995 St. Mary's College of CA
by Brother Alfred Brousseau
Species of the Month (December, 2007) : Oak Mistletoe
OAK MISTLETOE is an exciting plant. Not only do we humans get to kiss under it, but an amazing number of other species rely on it for food and shelter.
• The leaves of mistletoe provide rich protein for ring-tailed cats, chipmunks, porcupines, deer, and elk.
• Birds and small mammals burrow into mistletoe for warmth in winter. Martens are known to take cover in it, and dozens of birds, including Western Bluebirds and Golden-crowned Sparrows, have been seen huddling in clumps of mistletoe on a cold winter day.
• Common Bushtits, American Robins, and White-tailed Kites sometimes nest in Oak Mistletoe. Of four White-tailed Kite nests seen in Mendocino County by reliable observers, three were in the tops of clumps of mistletoe. (Dwarf Mistletoe, the spiky mistletoe seen on conifers, is home to even more bird nests: 43% of all Spotted Owl nests and, in northeast Oregon, a whopping 64% of all Cooper’s Hawk nests – as well as the nests of many other birds).1
• Mistletoe plants are either male or female. The male plants produce what may be the first nectar and pollen available in the spring for our native bees and honeybees.2
• Female mistletoe plants produce white berries that are an important cold season food for lots of birds, including Western Bluebirds, American Robins, Cedar Waxwings, Blue Grouse, American Crows, Common Ravens, California Thrashers, Mourning Doves, Band-tailed Pigeons, Phainopeplas, Varied Thrushes, and Hermit Thrushes. In the central valley Western Bluebirds choose their winter territories based on the availability of Oak Mistletoe berries!3 We don’t know the extent to which this is also true in counties west of the central valley.
• Mistletoe’s Latin name, “Phoradendron,” means “thief of the tree,” but in fact mistletoe harms trees very slowly. It synthesizes some of its own food through photo-synthesis, and sends a root-like structure called a “haustoria” down the limbs and trunks of trees to gather moisture and minerals. It is classified as a “hemi-parasite” and is an important part of healthy ecosystems. The more mistletoe in a forest, the more species of mammals and birds will live there, especially cavity-nesting birds.4
• Mistletoe is most likely to be found in places where birds like to perch, often in the tops of mature trees. Birds spread the sticky seeds by excreting them on branches or wiping them off their bills onto branches. They are sometimes transported on the feathers or fur of birds or mammals.
• Pomo Indians had ways of using mistletoe medicinally, though in most forms it is poisonous to humans. They particularly liked the Oak Mistletoe that grew on California Buckeye trees.5
• There are 1,300 species of mistletoe in the world, more than 20 of which are endangered. Excavations of Dusky-footed Woodrat middens (in which organic material is often preserved in a dark, hardened crystalline-like substance formed from urine) show that mistletoe has been around for 20,000 years.6 (Woodrats are also known as packrats, for good reason. Their urine-preserved nests serve as fascinating time capsules).
• The tradition of kissing under mistletoe may come from ancient Scandinavia, where mistletoe was considered a plant of peace. Enemies could declare truce under it, and spouses could kiss and make up.7 May mistletoe thrive and spread!
Exploring the Web of Life© is a monthly column written by Kate Marianchild of Ukiah, CA, with lots of help from her friends.
Sources:
1,2,4,6 “Not Just for Kissing: Mistletoe and Birds, Bees, and other Beasts,” USGS article: www.usgs.gov/newsroom/special/mistletoe.
3 “Winter resource wealth drives delayed dispersal and family-group living in western bluebirds,” Janis
L Dickinson and Andrew McGowan, www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1559973.
5 Plants used by the Indians of Mendocino County by V. K. Chestnut,Mendocino County Historical Society, 1974.
7 “Mistletoe,” by Sara Williams, University of Sasketchewan, Extension Division, the Department of Plant Sciences and the Provincial Government, www.gardenline.usask.ca/misc/mistleto.html
Also:
• U.S. Dept. of Agriculture, Forest Service: Mistletoes on Hardwoods in the United States,
www.fs.fed.us/r6/nr/fid/fidls/147.html
• Hastings Reserve, Oak Woodlands, Mistletoe: www.hastingsreserve.org/OakStory/Mistletoe2.html
• Bir Sur Chamber of Commerce, “Ring-tailed Cat,” www.bigsurcalifornia.org/ringtailedcat.html
• American Wildlife and Plants, A Guide to Wildlife Food Habits by Martin, Zim, and Nelson, 1951 (out of print but available online).
• Personal observations and personal communications with Jon Klein, Chuck Vaughn, and Bob Keiffer.
