the cedars (but really they’re junipers) of texas

The Cedars (But Really They’re Junipers) of Texas

Chase T. BrookeCounty Extension Agent – Agriculture & Natural Resources, Collin CountyTexas A&M AgriLife Extension Service

Learning Objectives

• Discuss the history of juniper distribution in Texas.• Identify the primary species of Junipers (spp. Juniperus) that naturally

occur across Texas.• Review means of field ID’ing Juniper species.

The History of Junipers in Texas

Why does the history of Texas Junipers matter?While broad biogeographical distribution of juniper species has not generally changed, the prevalence within that range has by and large increased dramatically; even in recent history.

Juniper Occurrence Pre-settlement

• Pre-settlement, the prevalence juniper species in Texas varied by region.

• Generally, Texas experienced more frequent disturbances, particularly fire.

• This kept relatively fire sensitive species such as junipers relegated to drainages, ridgetops, and other areas which were less likely to burn.

Juniper Occurrence in the Modern-Day

• Today, we have a critical management issue in regards to the rapidly increasing number of junipers in our endangered grasslands, prairies, and rangelands.

• This trend has been picking up even since the mid 20th century.

• Rapid afforestation is dramatically reducing the productivity, biodiversity, and sustainability of our lands in Texas.

Afforestation

• In the tropical rainforests, Deforestation is the critical change to that ecosystem.

• In Texas and the other great plains states, afforestation – or woody plant encroachment – is the greatest threat to our grasslands.

• This can be largely attributed to the removal of fire as a means of culling young pioneer saplings in open areas.

Juniper Biology

What is a Juniper?

• A juniper is a dieceous evergreen tree/shrub that occurs across pretty much every part of Texas.

• Very common in a ‘climax’ community.• Often is a main culprit of

encroachment into grasslands and prairies.

Why are they called cedars?

• Early in settlement by the Spanish and other Europeans, the native junipers of Texas were termed cedars due to their resemblance to the cedar trees of Europe.

• This has stuck around Texas and other regions despite the best efforts of botanists and other picky plant people.

Diecious Junipers

• As a diecious tree, junipers have male and female plants.

• (top) female trees host the fruit• (bottom) male trees have more

visibly cone-like structures.

Photo credit: jsuplick (top) and dbohlmeyer (bottom) on iNaturalist

Growing up

• Junipers start off as very prickly and spindly seedlings.

• As they move through their juvenile stage, they begin to lose a lot of that prickliness and have scaley leaves.

Photo credit: patmarks on iNaturalist

Resprouting vs Non-Resprouting junipers• From a management perspective, the juniper species of

Texas can be broadly split into either resprouting or non-resprouting species.

• A critical part of managing juniper is correctly identifying the species present, as effective management of juniper depends on the biology of the plant.

• A juniper is considered to be resprouting if, once the main stem is cut, killed, or removed, new shoots will sprout from the belowground bud zone on the root collar of the plant (Fig. 1).

• This requires very different management techniques compared to non-resprouting junipers, which will die off after the main stem is burned or removed.

• Generally, non-resprouting junipers are more susceptible and sensitive to fire. Additionally, older and larger trees are able to withstand fire effects better than younger ones.

Bud zone on a redberry juniper (J. pinchotti). Photo courtesy of Dr. Darrell Uekert.

Juniper ‘berries’

• The berries commonly found on juniper are actually fleshy cones.

• The extra flesh on the cones provides sustenance for a number of wildlife species.

• Seeds are often dispersed by birds• Hence, why so many tend to pop up near

good roosting spots (fences, powerlines, et cetera).

Photo credit: jefrobodeen on iNaturalist

The Juniper Species of Texas

Eastern Redcedar (J. virginiana)

• Common names: • Eastern red cedar • Red cedar

• Common juniper species found across the eastern portion of the state and the eastern United States.

Distribution of J. virginiana across Texas. (Brooke & Treadwell, 2019)


• Physical Characteristics• Tall, single trunked tree• Non-resrpouting• 40-70ft tall at maturity• Shallow rooted• Not as drought adapted as more

western species• Aromatic oils make the wood good

for repelling insects.

Photo credit: lanechaffin on iNaturalist


• Ecological Characteristics• Wildlife habitat & source of forage• Dominance of J. virginiana leads to

low species diversity

Photo credit: lanechaffin on iNaturalist

Ashe Juniper (J. ashei)

• Common names: • Ashe cedar • Ash juniper • Blueberry cedar

• A common sight across the Texas Hill Country, Ashe juniper also occurs in eastern Oklahoma and Arkansas.

Distribution of J. ashei across Texas. (Brooke & Treadwell, 2019)


• Physical Characteristics• Multi-stemmed tree• Non-resprouting• Short; seldom grows over 30ft tall• Fast growing; mature at 10-20

years old• Climax species when it forms

thickets.• May have white stripes on

branches

Photo credit: dasha98 on iNaturalist


• Ecological Characteristics• Suppresses growth of understory

plants.• Fire intolerant• Critical habitat for some

endangered species.• Golden cheeked warbler

• Rapid growth and establishment threatens open prairies and upland rangelands.

Photo credit: connlindajo on iNaturalist

One-Seed Juniper (J. monosperma)

• Common names: • One-seed cedar • Sabina

• Occurs in panhandle and trans-pecos regions of Texas

• So named because each cone has one seed in it.

Distribution of J. monosperma across Texas. (Brooke & Treadwell, 2019)


• Physical Characteristics:• Non-resprouting• 10-40ft tall at maturity• Cones (berries) are dark blue

and have one seed• Slow growing, ~6in height &

~0.5in diameter per decade.• Will stop growth in periods of

drought. • Produce seed at 10-30 years of

age, with crops every 2-5 years.

Photo credit: bob777 on iNaturalist


• Ecological Notes• Climax species• Competitive in dry, shallow soiled areas• Very susceptible to fire• Good habitat and forage for deer, bighoen sheep, bison,

and numerous small mammals and birds. • Provides year-round food via berries.• Notable birds which utilize fruit include:

• Northern flicker, steller’s jay, western bluebird, cassin’s finch, and more

Photo credit: jooeyleee on iNaturalist

Pinchot’s Juniper (J. pinchotti)

• Common names: • Redberry cedar • Pinchot’s juniper

• Redberry juniper is a multi-stemmed shrubby tree commonly found in the shallow and rocky soils in the northern and western parts of the state

Distribution of J. pinchotti across Texas. (Brooke & Treadwell, 2019)


• Physical Characteristics• Relatively fast grower. • Resprouting• Short tree/shrub; Individuals grow

3–15 ft tall, and reach maturity at 12 years.

• Most common resprouting species of juniper in Texas.

• Notable red or reddish-brown fruit.

Photo credit: cliftonladd on iNaturalist


• Ecological Notes• High intensity fire may kill

individuals. • Young saplings have higher toxic

monoterpenes than older trees. • Grasses such as buffalograss,

sideoats grama, and tobosa may stunt the growth of J pinchotti.

• Berries make good wildlife forage.• Low value, unpalatable browse

• Goats and sheep may be trained to prefer it though.

Photo credit: sotexnaturalist on iNaturalist

Alligator Juniper (J. deppeana)

• Common names: • Alligator cedar • Mountain cedar • Tascate

• More often found in the trans-pecos region of Texas. More common in northern Mexico and the American southwest.

Distribution of J. deppeana across Texas. (Brooke & Treadwell, 2019)


• Physical Characteristics• Single trunked• Resprouting• Monoecious• Grows very slowly, with 0.5in

diameter through the first ~170 years.

• Maximum longevity around 500 years

Photo credit: logan-berner on iNaturalist


• Ecological Notes• Very fire resilient.• Foliage is more palatable than

other juniper species.• Mule deer prefer it more than

whitetail deer.• Very strong resprouting capability

makes it difficult to manage

Photo credit: weedwatcher on iNaturalist

How to ID your juniper

Difficulties in ID’ing juniper species

• Junipers can be difficult to ID in the field

• They all fit a general, green, shrubby, and ‘juniper’ profile.

• 3/5 species in this presentation have characteristics that allow for easy ID.

• However, differentiating between J. ashei and J. virginiana is challenging.

• Lots of misidentifications on pages like iNaturalist

A quick test – ID these junipers

Photo credit: lanechaffin & bob777 on iNaturalist

Eastern Redcedar (J. virginiana) Ashe Juniper (J. ashei)

Redberry Juniper (J. pinchotti)

How to differentiate J. ashei from J. vir.

• Differentiation of J. ashei and J. virginiana can be quite difficult when side by side.

• Easiest place to start is to look at the location of the plant in Texas.

• If east of I-35, it’s J. virginiana. if west, likely J. ashei.

• Not reliable in areas of overlap in central Texas (eg. Travis county)

Picture tagged as J. ashei in Melissa, TX. Photo credit: chris41399 on iNaturalist


• Hall (1951) Juniper Key• Leaf Margins.

• J. Ashei has denticulatelyfringed margins, while J. virginiana has entire margins.

• Generally, i have found that ashe juniper leaves are rougher and more stubby than eastern redcedar.

J. Ashei (left), J. Virginiana (right). Photo credit: sambiology and johngonzales on iNaturalist


• Hall (1951) Juniper Key• Glands

• J. Ashei will generally lack glands on leaf scales, excepting older foliage.

• Glands can be hard to see, especially if not swollen or colored.

J. Ashei foliage on a ruler. Photo credit: gcwarbler on iNaturalist

Swollen glands present on older foliage

1 centimeter

The glands of J. ashei

Glands not readily visible on new foliage

Glands visible on older foliage.

Photo credit: sambiology on iNaturalist

The glands of J. virginiana

Photo credit: paulines on iNaturalist

Glands light colored, but consistently visible on foliage.

How to differentiate J. ashei from J. virginiana

• Hall (1952) – Branching Structure• J Ashei

• Starts branching out from the primary shoot near the ground.

• Tertiary shoots are more exaggeratedly alternate

• J. Virginiana• Branches upwards along the primary

shoot. • Differentiation via branching pattern

works on trees in their ‘shrub’ pattern. J. ashei in thickets may branch more similarly to J. virginiana.

Branching pattern of J. Ashei and J. Virginiana (Hall 1952)


J. ashei (top), J. virginiana (right). Note the branching structure from the primary stem.

Photo credit: rayallen84 and johngonzalez from iNaturalist.

My rules of thumb for field juniper ID

• Start by looking at botanical characteristics.

• Red fruit, glanded scales -> J. pinchotti• One fruit, brown seed, glands elliptic & flat ->

J. monosperma• Alligator-like bark scales -> J. deppeana• Blue fruit? -> J. ashei or J. virginiana.

• Another shortcut is to look at the location of the plant. Eg. J. pinchotti will not naturally occur in E. Texas.

Map of general distributions of 5 main juniper species in Texas. (Brooke & Treadwell, 2019).

Resources and Works Cited

• Anderson, Michelle D. 2003. Juniperus virginiana. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/junvir/all.html [2019, October 18]

• Brooke, C., Treadwell, M. (2019). Managing Texas Juniper with Prescribed Burning. Texas A&M AgriLife Extension Service.

• Hall, M. T. (1952). Variation and hybridization in Juniperus. Annals of the Missouri Botanical Garden. 39(1): 1-64

• Hauser, A. Scott. 2007. Juniperus pinchotii. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/junpin/all.html [2019, October 19].

Resources and Works Cited

• Johnson, Kathleen A. 2002. Juniperus monosperma. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/junmon/all.html [2019, October 18].

• Sullivan, Janet. 1993. Juniperus ashei. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/junash/all.html [2019, October 18].

• Tirmenstein, D. 1999. Juniperus deppeana. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/tree/jundep/all.html/ [2019, October 19].

the cedars (but really they’re junipers) of texas

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