Which of the following methods of applying borates to wood does not involve immersion?

The method of applying borates to wood that does not involve immersion is the process of spraying or brushing on the solution. This technique allows for direct application of the borate solution onto the wood surface, creating a protective barrier against termites and other wood-destroying organisms without the need to fully immerse the wood in the solution.

In this method, the borate solution can be applied uniformly across the surface of the wood, ensuring that it penetrates adequately to provide effective protection. It is particularly advantageous for treating wood that is already part of a structure, where immersion is impractical and would risk damaging surrounding materials.

Other methods mentioned, such as momentary immersion, pressure treatment, and long-term soaking, all involve immersing the wood into a solution or subjecting it to high pressure which facilitates deeper penetration of the borates. Such methods may be effective for certain applications but are not suited for all scenarios, particularly where the wood is already installed in a building or where a quick application is preferred. Thus, spraying or brushing on borates stands out as a flexible option that is both efficient and non-invasive.