Given that they've outlawed just about everything that ever worked to preserve wood, I'm anxious to read the thoughts other have regarding this topic.

Greg
Southern Nevada

As I recall you were supposed to soak the wood in this preservative a minimum of 24 hours, and then let it dry.

All the ingredients in the recipe are still available.

I have to give the obligatory cautions about working with combustibles near flame/heat.

Apply with anything that will allow heavy soaking; brush, rag, dip, spray even if you have HVLP or airless, provided you obtain saturation. Recognise that the end grain has greatest absorption and is also first entry of decay.

The problem with this preservative is short longevity, perhaps 3 years in ideal conditions, which good fertile soil would not provide...as Greg said, the things that preserve longer term are either off the consumer market or possibly toxic WRT pressure treated lumber.

Hmm. Kimmsr, I don't happen to have a container adequate size to soak those boards--grin. I had figured soaking was the optimal method. The author was preparing stakes which could easily be set into a bucket for the requisite 24 hrs, then paint the mixture on the parts above the soil level.

Alphonse, I already had the ingredients out in the shop and checked at the hardware stores should I need more and you are right, they are all still available. All of them posted warnings on the containers about avoiding use around heat and flame. Besides DH is a former firefighter and he'd pound it into my head if I didn't already know.

I didn't find this product in my initial searches on line but it looks interesting and cheaper than even a single gallon of turpentine. The website says it's available at a couple of hardware chains, two of which are in my area, so I'll call the one nearest us on Monday to see if they can get me any information on it.

Here is a link that might be useful: Lifetime Wood Treatment

The original recipe was developed by the USDA Forest Products Laboratory and reported in Rodale's Growing Fruits & Vegetables Organically, page 133 (currently out of print). The time period involved is not 24 hours but rather 3 minutes. The article suggests building a trough for longer length lumber - not an easy trick for an 8' length :-) - or painting the boards with several coats.

The alternative is using cedar (Thuja plicata) left untreated. In most areas of the country outside of the perpetually winter damp PNW, untreated cedar can last 12-15 years before needing to be replaced.

Western Red Cedar is naturally rot resistant while Eastern White Cedar is not so much. Black Locust is also rot resistant.

I used raw, not "boiled" linseed oil. It works great. Just make sure you provide enought time for it to dry (2~4 weeks).
Chaff

It's all about the wood. The heartwood of well-grown southern pine species is quite rot resistant, probably will survive in the ground untreated for 5-10 years. I have some white pine boards that have served as raised bed containment for about 5 years.

The sapwood of any species will rot very quickly. If you buy boards at the lumberyard pick through and avoid the ones with large amounts of sapwood. Eastern white cedar is not typically available in boards, only as shingles. Locust is not typically available. Western red is hugely expensive, and it is a very weak wood. White and yellow (southern) pine and spruce tend to be available everywhere. Spruce is a notorious rotter. All the pressure-treated (ACQ) products are southern yellow pine. If I was going to buy wood to treat myself I'd probably use southern yellow - it is affordable, it's strong, and the heartwood has some natural resistance.

Had never thought about it before but, I wonder if applying an epoxy coat to PT lumber would work to seal in the stuff in the wood folks are concerned about and last for many years. Don't know if the epoxy would have stuff in it that would be objectionable also.

Since wood is prone to rot quicker in the presence of water and soil microorganisms (fungi), would placing a sheet of heavy mil poly between the wood and fill material extend the life of a raised bed made from a perhaps lesser grade of wood than say, White Cypress?