Horse Fencing 101: Post Edition

Hello again! Whose ready to talk fence posts? I can feel your excitement already…I mean after all, who WOULDN’T get jazzed up over such a sensational topic! Right?

But seriously, after the hassle of deciding which type of fencing material would be best for our needs and the safety of our horses we were left with the realization that fencing materials did not come with the inclusion of fence posts. Naturally, after a few minutes of, “But why though?!”, it made perfect sense yet those few minutes were quite a sad realization.

Never one to turn down a challenge, the research began again. I don’t know if it’s possible but IF it is, I may have actually tired out the Google ‘search’ option. Now we had the option to go with metal T-Posts, Vinyl, or Wood posts to serve as the framework for our new CenFlex fence. Once again, I placed my primary need on strength and durability. as I didn’t want to have to do this again ANYTIME in the near future. Installing fence posts is a MAJOR undertaking and terribly tedious process…but I digress! Metal posts are incompatible with the particular type of Centaur fencing we chose as well as vinyl which brings us to our remaining option – wood -.

Now it IS strong and depending on the species or the treatment used can be exceptionally durable. What isn’t to love? Well… it IS the most expensive option and no one treatment type is created equal.

You have two options:

1. Natural – Osage Orange, White Oak, Redwood, or Red Oak are the best native species in the U.S. that require no chemical or pressurized treatment. I’ve listed them in order beginning with the most superior to rot, insect, mildew, and mold resistance.

Pro: No treatment necessary, each species natural resistances can offer from 15-40+ years of life before replacing.

Con: Hard to come by, expensive, and you will lose the uniform look of your fence as most are cut ‘roughly’.

2. Chemical – You have your choice of more Eco-Friendly options that are formed from water-based treatments such as CA-Preserve (Copper Azole) or more cost-effective options are that oil-based such as Creosote, CCA (Chromated Copper Arsenate), or Pentachlorophenol.

Pro: Much more cost effective than naturally resistant wood species and with certain treatments can last from 3-15 years.

Con: All chemical treatment types carry a measure of risk via handling, disposal, and how they affect the environment. Certain treatments are not suitable for residential and agricultural use -at all-.

Let me tell you, Osage Orange is near impossible to find. It’s like a wild goose chase in which you need to prepare yourself for endless circles with no answers, anywhere. I sought out white oak next. Lumber yards would not return my messages, forum posts looking for sellers went unanswered…it was a dark time in my research process. Eventually I had to consider that our only feasible option in our time crunch, would be going the chemically treated route. I feel I could write a small novel on the do’s and don’t’s of “treated wood” and its proper usages but I will spare you the essay and apply what was relevant to our situation:

Our farm is set up on well water and is used to not only irrigate the land but is our drinking and bathing water as well. When choosing a treatment for our posts I had to be certain that it would not ‘ooze’ over time (think sap dripping from tree bark) and pool about the base of our post, contaminated the soil and poisoning our horses. While ours are not cribbers or wood chewers, I had to consider the possibility they might try at some point and so the toxicity level, if ingested, came under consideration as well. Lastly, I had to be 100% certain that it would not risk the integrity of our underground fresh water source that we all count on.

That left one feasible option, which I also called and spoke with our county agricultural official on just to be safe, which was CA-Preserve or the Copper Azole treatment.

Please keep in mind, the Environmental Protection Agency (EPA) is constantly running new studies and tests on the efficiency and safety of various treatments. For example, twenty years ago Creosote was a widely accepted form of treatment based primarily around coal tar extracts, now it has been banned in nearly half of the U.S. As of right now, CA-Preserve is considered to be one of the most eco-friendly treatments available.

Once again I find myself saying, ‘You get what you paid for.’ The posts treated with CA-Preserve were over double that of any other treatment available but… not willing to risk our water source or run the potential of poisoning our soil (and consequently the acreage the horses graze on) we trimmed our budget elsewhere and went for this treatment.

Some basic rules to follow when looking to install posts for a horse fence:

1. Ideal post size/length: 4x4x8.
2. For proper strength you should have a minimum of 4″ posts though 5″ is preferable and 6″ is recommended for any corners and posts surrounding gates.
3. Your fence should be at least 5′ tall above ground and 3′ below ground for a total of 8′.
4. Posts should ideally be no more than 12′ apart. We went with 10′ for our fence. (The closer together, the stronger the fence.)
5. All end posts and posts surrounding gates should be set in concrete for stability.
6. If possible, every third post should have 2 feet of packed soil, 6″ of concrete, and 6″ of packed soil on top.
7. All other posts should be packed down tightly with soil.

I hope this helped some! Now to patiently await our lumber delivery… I can be patient, I hope…

Cheers!