“Cedar” Trees: Understanding the role of the Ashe juniper in Central Texas History and Ecosystems
Ashe Juniper
(juniperus ashei)
Not cedars at all, but members of the juniper family, the term “mountain cedar” was commonly used because the tree had a cedar-like smell.
Much maligned in Central Texas, the Ashe juniper, has a unique role in the hill country ecosystem. Not only does the mature tree provide shelter, food (berries), and nesting material (bark shreds) for native animals, when Ashe juniper seeds germinate in degraded soils, the bushy new growth that results provides critical cover and organic matter to help heal the land over time. Seeds that fall on more balanced, healthy ground usually develop into tall trees that are similar to Live oak or cypress in appearance.
Photo by Elizabeth McGreeve/mountaincedars.com
When they mature in 40 to 60 years, these “tree” cedars develop the shredded bark that is critical to the nesting habits of the endangered Golden-cheeked Warbler.
Early settlers to Texas recorded Ashe junipers in excess of 60 feet tall with trunks as large as 44 inches in diameter.
Photo of Golden Cheeked Warbler by Tom Hausler
Shaggy bark of a mature Ashe Juniper
Seasonal Pollen
“Cedar Fever”
The pollen of the Ashe juniper is irritating to most and an allergen to many. The male Ashe juniper releases its pollen in mid-winter for up to three months and the airborne particles create a dusting of yellow everywhere. This pollen can ride the wind for up to 200 miles.
Like any seasonal pollen, steps can be taken to lessen the impact on sensitive sinuses.
Cedar Pollen cones - photo by Eva Frost
Myths and Facts
Myth # 1 – “Cedars” are Water Hogs/Cause Drought
FACTS: An early study based on a single tree resulted in the myth that Ashe juniper trees use 33 gallons of water per day. Newer studies have shown that the Ashe juniper actually uses less water than similarly sized live oaks.
When situated on fractured limestone, mature Ashe juniper trees have deep root systems that help channel rain water into aquifers and make the trees fairly drought resistant.
Myth # 2 – “Cedars” cause damage to the land
FACTS: While bushy Ashe juniper are often prevalent in areas that have been over-grazed or that contain sub-standard soils, they are not the cause, but rather the result of damage.
Poor soils or exposed limestone cause Ashe junipers to develop as “pioneering” bushes instead of trees. The bushes reduce erosion caused by rain striking naked soil, add organic matter to the soil and creates shade that encourage micro-organism growth.
Cedars do not “choke out” grasses and other trees but are some of the first to appear in damaged areas.
Myth # 3 – “Cedars” are Invasive
FACTS: Junipers have been a part of Central Texas for thousands of years as evidenced by the discovery of fossilized pollen found in the Friesenhahn Cave in Bexar County, Texas.
Early writings (prior to 1860) of settlers and explorers indicate that Central Texas was a patchwork of roughly half heavily wooded and half open grassy areas. Many of the large Ashe juniper trees reported would have been several hundred years old.
Ashe junipers were largely clear-cut or burned by early settlers who needed the wood for construction and fencing and wanted clear land for farming. Very few of the original old growth trees exist today.
Managing Ashe Juniper
Matured, healthy Ashe juniper trees should not be removed because they are important to native wildlife and the ecosystem. These will be at least 40 and possibly several hundred years old and most often grow in woodlands.
Ashe juniper berries - photo by Eva Frost
Where bushy cedar growth occurs, it indicates degraded soils. If you desire to remove bushy cedar to create a more open prairie, either wait until the bushy cedars improve the soil or plan to fortify the soil following removal to support wildflower and native grasses. Avoid wholesale removal of the bushy cedar since that can result in soil erosion.
Bushy cedars are easy to remove by cutting them off below the lowest green growth. Cut thus, they will not re-grow. Cut branches can be laid on the ground across the grade to create a natural water break and a nursery for seedlings to grow.
Pollinators
Ashe juniper is a larval food plant for the Juniper Hairstreak .
Juniper Hairstreak photo by Eva Frost
Learn More
Read the book, “Wanted! Mountain Cedars; Dead and Alive, by Elisabeth McGreevy, mountaincedars.com
Watch this video: Arborist Dan Gardener dispels myths about Ashe juniper, presented by Balcones Canyonlands Preserve
