Pressure treated lumber and raised beds
 

I was in Home Depot the other day looking at lumber for building raised beds. I asked the salesman if the new pressure treated lumber (ACQ treated) was safe to use now for making vegetable raised beds, and he said a resounding NO.

Googling on line here, all the articles I find suggest the opposite. What can anyone tell me about it. They no longer use the older treatment that had arsenic in it.

If you don't use it, what have you used. I hate the thoughts of 2" thick cedar boards when I want to build them 18" deep. $$$

I've read that regular Douglas fir boards lined with plastic can last 4-5 years easily, possiblely 6, so I would just go for cheaper untreated thick lumber.
My own beds, I used double hardie plank cement boards that are painted on both sides, they are 6 years old now, no sign of any decay. It looks like they will last a long time. They are no t as easy to work with as wood, harder to drill holes and cut.

Down here where termites are a constant threat any untreated lumber won't last but a couple of years. My beds are all over 35 years old and made with the old stuff that has arsenic in it. Even with the arsenic some of my boards that obviously didn't have enough got eaten by termites but most are solid as can be but severely warped after all those years. I don't think the arsenic is a real problem any way since worms don't seem to mind it at all and tend to concentrate right up next to the boards. If it is poisoning me it is doing it really really slowly.:?:

Bill

I use pressure treated lumber and feel comfortable doing so. I have two raised beds, for now, probably will add a third one in the spring.

Well my take on this is this :

1-How much of that chemical ( whatever it is ) actually leaks out of the lumber ?
2- Say "x" amount leaks out. Where does/will it travel ? Downward or side way ?
3- How much of it gets to the vegetable roots, a foot or more away ?
4- Do plants (tomato) actually uptake any of that ?
5- If the plants uptake some of that, how much of it end up in the tomato that we eat ?
6- How harmful is that chemical in very low ppm ?

So when I put all those question together, I am comfortable taking that minute risk.

I have to add that I have only made raised bed with cedar board , up in WA where cedar lumber is not very expensive. I used the kink that is manufactured for fencing : 5/8" x 5 1/2" x 6'.
A week ago I was at Lowes . They were selling those boards for $1.58 a piece. My buddy and I bough some and made a him a bench. He wants to make few raised beds too.
I, myself am going to buy some treated lumber to make posts around the garden.
YMMV

Bill is right about the South. Non treated lumber - 2 years max. I use treated, and they are good for 7 years. No brainer.

I'm in a wet/damp climate for much of the year though winter and snow may slow down my raised beds from rotting. I use 2x12 and replace as needed...each one only once in all these years. Almost 20 now.
I have read the new pressure treated is probably safe but still an un-known 'probably'. It isn't so much the leeching for me but how often i'm working on and around the wood...kneeling on, touching all the time. Then harvesting crops and salad greens. Double digging takes soil from the edge to the middle...and i don't spray and practice organic so makes sense to me to keep pressure treated to fence posts only.

Home Depot has an expert on this sort of thing?:?

Pressure treated for me as well and the worms are as happy as a clam.

Worth

In the past, I used untreated logs notched like a cabin in the corners. They last a very long time and decomposition is natural to Mother Earth.

[QUOTE=dustdevil;602976]In the past, I used untreated logs notched like a cabin in the corners. They last a very long time and decomposition is natural to Mother Earth.[/QUOTE]

Our cedar AKA juniper would be good for that here, I have no idea what they would cost.

[url]http://www.naturalhandyman.com/iip/infxtra/infptforraisedgardens.html[/url]

To each its own.

Yes, BibVanVader, That was one of the articles I read. It is very dry here and hardly ever rains. However, the soil will get wet from being watered frequently.

Do any of you in dryer climates use the untreated lumber? If so do you stain or seal it?
Thank you all for you input. It gives me good food for thought.

[B]"RAISED BEDS AND FALSE ECONOMIES"[/B]

Erica did a comparative calculations for you of materials to use for raised beds in the article below. I think she lives near Seattle where there is a lot of rain during the winter.

[url]http://www.nwedible.com/raised-beds-and-false-economies_18/[/url]

There's a piece of research where food crops were grown in pure treated lumber sawdust as a medium, AND they used the old stuff, not the new. The only food crops that they could get to be above the government's safety threshold for arsenic in food were root crops, and even then it was only in the very tip of the root, which people would typically not eat anyway.

If there was anything toxic about lumber, it would have shown up by now and affected the countless people who work with it every day.

Some Info
 

[COLOR="DarkOrchid"][SIZE="4"][FONT="Century Gothic"][/FONT][/SIZE][/COLOR]Here is a link to a good youtube channel for you, he does an experiment with treated lumber. I personally plan to use pressure treated in my organic garden. I believe the wood at my Home Depot is MCQ...[COLOR="DarkOrchid"][/COLOR][URL="https://www.youtube.com/watch?v=KCXDo1Qjdm8&t=4s"]https://www.youtube.com/watch?v=KCXDo1Qjdm8&t=4s[/URL][SIZE="3"][SIZE="4"][/SIZE][/SIZE][FONT="Comic Sans MS"][/FONT]