Boracare does need to be diluted depending on what you are intending to use the product for. For an active infestation of a wood destroying insect, you will use 1 gallon of hot water with 1 gallon of Boracare. The percentage of active ingredient is 23% in that dilution.
2:1 parts water to Boracare – 16% - foaming or misting application for termites or carpenter ants; hardwood floors for some wood-infesting beetles
3:1 parts water to Boracare – 13% - remedial control of Fungi and Algae on wood less than 4 inches thick
5:1 parts water to Boracare – 9% - most preventative or pre-construction treatments.Bora-Care is a very safe product and it is considered a green product as well. Typically, it takes about an hour for the surface of the wood to dry. After application has dried completely, it should be perfectly fine for children and pets to re-enter the house. Please read the BoraCare product label for complete usage instructions. Boracare does have to be applied to raw, untreated, unpainted wood.
As long as the top is sealed then you can safely apply Boracare to the underside if unsealed and it will penetrate through the wood. It would be recommended to allow the butcher block to dry for 24-48 hours before using again. Any food contact surfaces treated with Boracare must have a sealant applied after the Boracare has dried.
No Bora-Care, like any other borate product, cannot be used on trees or plants. It is for cut lumber only. Borates will kill any living plant, shrub, grass or tree. Termites do not attack live, healthy trees. If you have termites in a tree you would need to treat the nest directly by drilling holes into the dead parts of the tree where the colony is infested. This can be done with something like Dominion 2L. Most people are primarily concerned with protecting the big investment, their home, and Dominion or or Termidor would be the best product to use for that. Termidor is the top product and can last 10 years in the soil, whereas Dominion will only last 5-7 years. It is only labeled to be used adjacent to the structure, though.
Borcare can be applied to untreated wood only.
No, Boracare should only be mixed with water and applied to raw wood.
Any untreated or unstained wood, including plywood, would benefit from an application of Boracare to help protect it from wood infesting pests, fungi and dry rot. If you do have an active infestation of pests in the wood Boracare would be the best treatment for that as well before you stain. When treating wood that may be exposed to rainfall, be sure to apply a water sealant after the Boracare application has dried.