I am not totally sure what the logs are treated with. It seems to be a light reddish stain. They are available at any Home Depot. They might be able to answer what kind of stain they use. It is not pressure treated or creosote. They sell this in the landscaping supplies area so I think it is compatible for gardens. They only come in 1 length, 8 feet long. I have also seen them at Lowe's but they are a bit smaller in diameter but also a little harder wood and do not rot out as fast. When the logs are cut to be used as posts, they tend to rot out at the base and I have had to replace a few. Most of the horizontal laid pieces are doing pretty good after 4 years. It would have been better to place a barrier (black plastic mat roll) on the back side before back filling with soil.