1. James Carter NRECA/WQC Inc.
Utility pole species
James Carter
NRECA/WQC Inc. (:

2. SPECIES FACTORS Availability Cost Treatability Strength Shape
Under strength – density in the outer 2-3 inches, controversy over plantation grown material – note all wood is generally “managed”, no more natural stands of timber

3. Species Used for Distribution/Transmission Poles
Southern Pine
Red Pine
Ponderosa pine
Lodgepole pine
Douglas Fir
(Coastal)
Western Red Cedar

4. SOUTHERN PINE Thick sapwood layer that treats easily
80% of all wood distribution poles
Availability good in distribution sizes, poor in transmission lengths
Straightness good in distribution, poorer in transmission
Light to moderate checking
Knots well scattered, but prone to large knots in longer lengths
Fiber stress of 8000 psi
Climbability varies considerably, depending on treatment

5. RED PINE Thick sapwood layer that treats easily
Rapidly gaining popularity in distribution sizes
Availability good in distribution sizes
Straightness generally good
Moderate, occasionally large surface checking
Knots small to moderate in size, occurring in whorls
Fiber stress of 6600 psi
Climbability good

6. PONDEROSA PINE Thick sapwood layer that treats easily
Availability very limited
Straightness generally good
Moderate to large surface checking
Moderate knots, well scattered
Fiber stress 6000 psi
Climbability varies considerably depending on treatment

7. LODGEPOLE PINE Variable sapwood thickness
Availability limited
Straight
Moderate to large checking
Moderate knots, scattered, often associated with bark
Fiber stress 6600 psi
Climbability varies considerably depending on treatment

8. DOUGLAS FIR (COASTAL )
Thin sapwood layer requires modification to insure adequate treatment
80% of large wood transmission poles
Availability good in both transmission/distribution lengths
Straightness very good in all lengths
Moderate to large surface checking
Moderate knots, well scattered
Fiber stress 8000 psi
Climbability fair to good, depending on treatment

9. WESTERN RED CEDAR
Thin sapwood layer requires modification to insure adequate treatment
Availability limited/expensive
Straightness very good
Moderate to large surface checking
Knots moderate to large, scattered, often numerous
Fiber stress 6000 psi
Climbability excellent

10. Species Characteristics
WESTERN RED CEDAR
LODGEPOLE PINE
PONDEROSA PINE
RED PINE
SOUTHERN PINE
DOUGLAS FIR (COASTAL)
SHAPE
-Sweep
-Crook
Straight
N.A.
Mod. Straight
Prone to sweep
KNOTS
Mod/Large/Scat
Mod/Num/
Bark
Mod/Scat
Small/mod/whorl
Mod/large/scat
Mod/scat
CHECKS
Mod/large
Mod
Light/mod
GAFFING
-Oil
-CCA
Excellent
Good
Moderate
Mod/Poor
Good/Mod
Poor
FIBER STRESS
(psi)
6000
6600
8000
SAPWOOD THICKNESS
½ “ to ¾ “
¾ “ to 2 “
2 “ to 3 “
2 “ to 4 “

11. Wood Preservatives - Safety - Effectiveness - Permanence - Economics
Safe – Non-corrosive, non-noxious, doesn’t promote combustion
Effective – Protects against fungi & insects
Permanence – long term service life, no soil or water environmental issues
Economics – priced to be competitive with other materials

12. Major Preservative Types
Tar Oils
Creosote
Clean Creosote
Organic Solvents (Oil borne)
Penta
Copper Naphthenate
Water-borne
CCA (Chromated Copper Arsenate)
ACZA (Ammoniacal Copper Zinc Arsenate)

13. Creosote
Brownish-black oily liquid containing a large number of different chemical compounds. By-product of the coal tar distillation process. Oldest wood preservative, used worldwide for over 150 years.

14. Creosote ADVANTAGES DISADVANTAGES
Documented record of performance dating to the 1800’s
Very low solubility in water
Normally non-corrosive
High electrical resistance
Excellent climbability, flexibility
Restricted use pesticide
Surface bleeding can cause handling, exposure environmental problems
Preservative migrates over time
Dark color may not be esthetically acceptable
Noxious odor
Availability limited
Common on development of clean creosote

15. Organics (Oil-borne) PENTACHLOROPHENOL (PENTA) COPPER NAPHTHENATE
A manufactured broad spectrum biocide that is dissolved in a mixture of hydrocarbon solvents for treatment. Created by the direct chlorination of phenols. In commercial production since 1936.
COPPER NAPHTHENATE
A combination of metallic copper dissolved in naphthenic acid, mixed with petroleum based solvents for treatment. In commercial production since the 1930’s.

16. Pentachlorophenol (penta)
ADVANTAGES
DISADVANTAGES
Documented record of performance dating to the late 1930’s
Very low solubility in water
Non-corrosive
Excellent climbability, flexibility
Good surface cleanliness
Esthetically acceptable appearance
Availability excellent
Restricted use pesticide
Preservative migrates over time
Odor of carrier somewhat noxious
Surface bleeding can adversely affect handling

17. Copper Naphthenate ADVANTAGES DISADVANTAGES Expensive
A non-restricted use pesticide with low mammalian toxicity
Documented record of performance as a supplement since the 1930’s
Low solubility in water
Non-corrosive
Excellent climbability, flexibility
Color is esthetically acceptable
Expensive
Availability limited
Objectionable odor in fresh treated material
Requires active solution filtration to eliminate greasy surface deposits
Preservative migrates over time
Most experience is with CuNap combined with other preservatives; recent early failures caused great concern

18. Water-Bornes ACZA – Ammoniacal Copper Zinc Arsenate
A combination of copper, zinc, and arsenic dissolved in a solution of ammonia in water, used primarily to treat western species.
CCA – Chromated Copper Arsenate
A combination of copper, chrome, and arsenic dissolved in water.

19. ACZA ADVANTAGES DISADVANTAGES
Documented record of improved performance vs. ACA
Chemical fixation virtually eliminates preservative migration
Clean, dry surface
Esthetically acceptable appearance
Improved resistance to woodpecker attacks?
Availability good
Restricted use pesticide
Harder surface increases climbing difficulty
Reduced flexibility, higher susceptibility to shock loads
Potential hardware corrosion problems from residual ammonia

20. CCA ADVANTAGES DISADVANTAGES
Documented record of performance dating to the late 1930’s
Chemical fixation virtually eliminates preservative migration
Clean, dry surface
Esthetically acceptable appearance
Availability very good
Lowest priced preservative
Additives available to improve climbing
Restricted use pesticide
Harder surface increases climbing difficulty
Reduced flexibility, higher susceptibility to shock loads
“Glowing” due to chrome content may increase damage from fire