Outdoor fence (spruce, larch and oak): how to treat?

[df woodworker]

I'm building a fence out of spruce and larch boards that still have the bark on one side, and the fence posts will be oak (10 cm x 10 cm). See the photos (raw spruce and larch boards, and an example of a completed fence made with them). The oak posts will be set in cement, and the larch/spruce boards won't come all the way to the ground. What's the best way to treat it? I see on an old thread here that it's not necessary to oil the oak. The person who made the fence in the photo used the same larch/spruce/oak mix and didn't treat it at all. I'm wondering if I should treat the larch and spruce at least. Btw I'm in northern France, where it rains a lot. Thanks.

 

[Torx]

I erected an oak fence with woven panels about 8 years ago, in England where it rains a lot. I didn’t treat it and it’s still in perfect condition. I did wrap the posts with these

https://shop.postsaver.com/product/...CtdCUv9G161nxtneEQMxvJTtfs5tWnE4aAilOEALw_wcB
I would think the bark would invite insects even if treated, and assume it will all fall off eventually anyway?

 

[df woodworker]

Thanks, I'll look at the wraps. I plan to pour the concrete in the hole up to ground level and a bit above, so I think that will prevent most of the contact from the soil, but the wraps might be a good idea. The bark will fall off eventually. I could treat it again if necessary down the road. I'm not sure that the treatment is necessary though.

 

[Inspector]

Ensure drainage out the bottom by putting the post on compacted gravel and then pouring the concrete. If you hold the post up and the concrete seals the bottom the water will sit around the post and rot it out much faster.

Pete

 

[adidat]

A 'friend' has had good results with creacote cut 50/50 with used engine oil. Smells awful for a week and gives a pretty black finish, but has held up well for 5 years.

Adidat