Wood treatment

I have been searching for a environment friendly wood treatment.
I compiled everything in an email that I sent to David.
I am just going to transcribe the email here, so you can see the possibilities that I found, and who knows tell us about some more or your experience with the same question.

"(...)

Talked with my father and brother and they told me about:
- óleo de linhaça

- cuprinol
- óleo de teca

The first one we already know. http://www.leroymerlin.pt/Site/Produtos/Pintura-e-drogaria/Produtos-para-madeira/Vernizes-protetores-e-oleos/17709986.aspx

Cuprinol: http://www.leroymerlin.pt/Site/Produtos/Pintura-e-drogaria/Produtos-para-madeira/Tratamentos/12279323.aspx - this one is not natural
Óleo de teca: http://www.leroymerlin.pt/Site/Home.aspx#q=%25C3%25B3leo%2520de%2520teca - this is natural

From the research that I did they speak about Borax.

Pine Tar:"The product is still used to a great extent for wooden constructions such as shingles, bridges, boats, barges and cottages. The Swedish Cultural Management recommends pine tar as surface treatment of wooden church roofs and other cultural buildings made of wood. There are examples of stave churches that have been preserved with pine tar for nearly a thousand years with very few intervals of maintenance. "  at http://www.solventfreepaint.ca/pine-tar.htm
 "Pine tar is a sticky material produced by the high temperature carbonization of pine wood in anoxic conditions (dry distillation or destructive distillation). The wood is rapidly decomposed by applying heat and pressure in a closed container; the primary resulting products are charcoal and pine tar." at http://en.wikipedia.org/wiki/Pine_tar )
Aqui fica a receita que referem no mesmo site:
"An Ancient Pine Tar Recipe: Thinning with organic boiled linseed oil is recommended to obtain faster penetration and reduce stickiness. Apply warm if possible.

1. Combine equal parts of Genuine Pine Tar and Purified Organic Linseed Oil - boiled, 100% cleaned and sterilized linseed oil from Allback, Sweden.
2. Heat to 80 degrees F and mix thoroughly.
3. Apply warm if possible."

Essential oil:
"Fumigant Toxicity of Essential Oils to Reticulitermes flavipes"
http://naldc.nal.usda.gov/download/33751/PDF

Boiled Linseed oil and coal:

http://www.selfsufficiencystore.com/blog/natural-wood-treatment

Put the wood bars inside of a mix of water and lime

agriboard e hemp board
http://www.borax.com/products/solubor/ - SOLUBOR - I think is borax with something else
TIMBOR - they say is the same thing as SOLUBOR but for wood instead of agriculture: https://www.youtube.com/watch?v=iX46F5-cn7Y and https://www.youtube.com/watch?v=pFQh18da6ds - https://www.amazon.com/Tim-bor-Professional-Insecticide-Fungicide-1-5/dp/B00282L6T2
This is the company that I spoke that sells organic things for building: http://www.diretoriode.com/pt-br/biohabitat-comercio-materiais-de-construcao-lda/. They don't have an email, so I have to call them. http://www.centrohabitat.net/pt/associado/biohabitat-lda"


We decided to go with the pine tar and the linseed oil.

With love,
Raquel