   Growing Manzanita - February 26, 2003 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County Of all the native shrubs in north central Arizona, manzanita is the most popular. Gardeners (including myself) love this plant for its graceful form, reddish bark, flowers and fruit, and drought tolerance. For these reasons, people want to plant more of it in their landscapes. However, it is not readily available in most retail nurseries probably because it is somewhat slow to grow and outplanting success can be variable. Manzanita is related to heather (Family: Ericaceae). Four species of manzanita are found in northern Arizona. In Yavapai County, we have two species: Pringlei manzanita (Archtostaphylos pringlei) and pointleaf manzanita (A. pungens). Pringlei has grayish green, rounded leaves and pointleaf has bright green leaves with a pointed leaf tip. Both grow between 2 and 4 meters tall, have reddish bark, and grow on slopes between 3,500 and 7,000 feet in elevation. The two species often grow on the same site, and under these conditions, they are probably hybridizing. These two species have been grown by local nurseries specializing in native plants. Bearberry or kinnikinnick (A. uva-ursi) is a prostrate growing manzanita species. It creeps along the soil surface reaching a height of 15 cm (6 inches) and is grown commercially by nurseries in California. It is native to Arizona in the Lukachukai Mountains of the Navajo Nation. This is a good choice for landscapes due to its low growth and decreased fire hazard. Greenleaf manzanita (A. patula) grows on the north rim of the Grand Canyon and is also commercially available. Some backyard gardeners enjoy propagating their existing manzanita plants. This is most easily done using the layering technique. Here a tender shoot is "pinned" (using a "U" shaped piece of wire) into the soil where it is left to take root for a growing season. You should slightly wound the stem with a sharp, clean knife and give it some supplemental water to promote root growth. After roots become established, the rooted plant can be severed from the mother plant, allowed to recover, and transplanted in fall following recovery. Manzanita plants can also be grown from seed although some treatment is necessary to break the hard seed coat. To prepare the seed, fruits are soaked in water to remove the fleshy pulp. Commercial growers soak seeds in sulfuric acid for 3 to 6 hours. Sulfuric acid is very caustic and not recommended for home use. In nature, manzanita seeds germinate following fire. Fire provides a combination of exposure to heat/smoke and seedbed preparation. To mimic this natural process, some propagators sow seeds in a flat and burn a 3-4 inch layer of pine needles on top of the seedbed. Seeds may take a year to germinate. Once seedlings germinate, they are transplanted to nursery containers. This is the technique I would recommend for adventurous home gardeners. Before you get totally inspired to grow manzanita, I should interject a word of caution: living manzanita plants contain a high percentage of volatile compounds, which burn like a torch when ignited. They also carry a large amount of dead wood, making them all the more flammable. Manzanita can act as a ladder fuel in landscapes, especially when planted adjacent to flammable structures such as homes, decks, fences, and trees. Ladder fuels carry fire from the ground where it can be controlled to treetops where it is difficult to control. Flame lengths of manzanita can reach eight times the height of the shrub (i.e. a five foot tall manzanita can generate a 40 foot flame). Manzanita is an integral component of our chaparral vegetation community and provides benefits for wildlife, birds, and insects. Hummingbirds and butterflies are attracted to the urn-like flowers. After reading this, I hope you can appreciate the difficulty of growing manzanita commercially. Finally, please give strong consideration to use and placement of manzanita for wildfire risk reduction. The University of Arizona Cooperative Extension has publications and information on gardening and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 ext. 14 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://ag.arizona.edu/yavapai/anr/hort/byg/. |