DIS-TRAN Steel Blog

3 Common Crossarm Preservatives

Posted by Melissa Hines on Jun 22, 2015 11:03:00 AM


Are you treating your wood right?

Wood utility poles and crossarms are common objects seen throughout our communities along the streets and in our yards. These poles and crossarms are used to support and run electrical lines to our homes and businesses - making these products vital to our daily lives. Prolonging the useful life and structural integrity of these items is aided by treating the wood prior to installation.

Wood treatment refers to protecting wood from damage caused by insects, fungi, decay, climate and extreme weather conditions. Treating wood with the right chemical preservatives can extend the useful life and protect it from the harsh environment. Choosing the right wood preservative can save an utility time, frustration and money. The three most common wood treatments include:

  • Pentacholorphenol (Penta)
  • Chromated Copper Arsenate (CCA)
  • Creosote.

Pentacholorphenol (Penta) has been a preservative and maintenance staple of the Canadian and American utility industries for more than 60 years. Penta is a broad spectrum biocide and was previously used in herbicides, algaecides, fungicides and disinfectants. Today, the use of Penta in the U.S. and Canada is limited to wood preservation applied by trained-certified pesticide applicators. The production and use of Penta is regulated by the EPA and is an approved preservative in the American Wood Protection Association. (AWPA) Since its introduction in the utility industry, Penta has become the preferred wood preservative for poles and crossarms and is used extensively for treatment of laminated beams since it will neither wet the wood nor effect the glue joints. Penta can be used as a wood preservative for both Douglas Fir and Southern Yellow Pine crossarms.

Chromated Copper Arsenate (CCA) is a water based wood preservative. It is a mix of chromium, copper and arsenic. Recognized for the greenish tint it imparts to wood, CCA has been extremely common for many decades and is used primarly on Southern Yellow Pine poles and crossarms. DIS-TRAN Wood Products, LLC provides this alternative wood preservation to its customers making up about 5% of the crossarms we supply.

Creosote is one of the oldest of the commercial  preservatives. It is made by distilling coal tar and is often thinned with a light oil such as diesel fuel or mineral spirits. The color of Creosote is usually dark brown to black with an oily appearance and odor. Most wood treated with Creosote is used in marine pilings, utility poles and railroad crossties.


At DIS-TRAN Wood Products, LLC, we not only manufacture a complete line of Douglas Fir and Southern Yellow Pine crossarms, but we also house our own treatment facility. Our treatment plant is located adjacent to our manufacturing facility in Pineville, LA. DIS-TRAN Wood Products, LLC have three trained-certified applicators onsite who follow all industry and environmental standards. With these three professionals onsite, DIS-TRAN Wood Products, LLC can treat approximately 1,300 arms with Penta on a single eight hour shift. Having our own onsite treatment plant allows us to have a fast response for storm emergenies. About 95% of the crossarms we manufacture are treated with Penta. 

Using the right chemical preservative for treating wood can greatly increase the life span and save a lot of time and money. Is there a wood preservative treatment you prefer to use? Would you like to see DIS-TRAN Wood Products, LLC offer an alternative wood treatment?  Leave us a comment below.  We would love to hear from you.



Check out our Easy to follow Preparation Plan for when storms are threatening you and your customers.Preparation for Storms

Tags: wood crossarms, southern yellow pine, douglas fir, crossarms, penta, wood treatment, chemical preservative, AWPA, CCA, wood preservative

7 Obvious Signs to Look for in Wood Distribution Crossarms

Posted by Brooke Barone on Jan 23, 2014 3:45:00 PM

Without knowing all the Rural Utilities Service (RUS) or American National Standards Institute (ANSI) specifications off the top of your head, it can be hard to decipher what is considered “on grade” relative to  wood distribution crossarms. However, here are a few general signs that can help you determine if “The Wood is Good”.

1. Size- review the section size of the arm. It’s a simple measurement; when you purchase a particular size, make sure it meets that measurement.

2. Tolerance- this is the allowable variation between the size specified and what may be supplied, which for both RUS and ANSI, can be plus one-eighth of an inch to minus zero.

3. Density- for close grain material, there should be a minimum of six growth rings per inch on at least one end. There are exceptions to the rules, such as having five rings, but it has to be with half or more summerwood present.

4. Drilling Pattern- this can either be one of the industry standards or specified by the end user. However, hole diameter and spacing must be correct, regardless of the standard.

5. Splits- are a separation of the wood from one face to the opposite or adjacent face and they are not allowed.

6. Seasoning Checks- “cracks” that can form when the wood is dried. If dried improperly, the check could go too deep; they are limited in length and width.

7. Shake- separation within the same grain; generally a cause for rejection but may be considered acceptable by some if more than one inch from the face. 

wood distribution crossarm

While the seven listed above are more visual signs, there are also more in-depth ways of knowing if the quality of the wood is good. Below I’ve listed out just a few terms that can come up when inspecting wood distribution crossarms under RUS specifications.

Pitch and bark pockets are concave areas on the surface formed from collecting pitch or bark trapped between growth rings. They are limited in number and size on the top of the crossarm as they hold water.

Insect and pin holes are from insects burrowing into the wood. No insect holes are allowed over 3/32” dia. and “scattered” pin holes are allowed less than or equal to 1/16”

Wane is an absence of wood on an edge or corner due to any reason but an eased edge and though allowed is limited in size

Compression wood is abnormal and often brittle wood formed on underside of bent or leaning trees; is not allowed on any face

3 Forms of Warp:

1. Crook is permanent bending of the lumber edgewise; limited

2. Bow is permanent bending of the lumber flatwise; limited

3. Twist is a permanent spiraling of the lumber; limited

Heart and sap stain is discoloration due to exposure to the elements; heart stain is not allowed but medium stain sapwood is acceptable

Decay is disintegration of wood due to fungi and should not be present in the wood

Slope of grain is grains direction relative to the ends of the piece; limited based on section size

Heart center is when the piece of lumber includes the very center of the log; is not allowed for Douglas-Fir but is acceptable in Southern Yellow Pine

There are countless rules and requirements that we could go into, but it can get a little confusing. If you would like to know more, you can download our RUS Cheat Sheet for Wood Distribution Crossarms to find out more unique requirements. 


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Tags: wood distribution crossarms, wood crossarms, crossarm drilling pattern, pitch and bark pockets, slope of grain in wood crossarm, southern yellow pine, douglas fir, heart center of lumber, compression wood, rus rural utilities service, ansi american national standards institute, wane wood

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