A. The tax levied by this chapter shall not apply to individual owners of timber who occasionally sever or cut such timber from their own premises. Such owners, however, in order to qualify for the exemption must use the timber in the construction or repair of their own structures, buildings, or improvements, or for their home consumption, or in the processing of their own farm products.
B. The tax imposed by this chapter shall apply to any forest products severed from land owned either by this Commonwealth or the United States, where the forest products severed enter commercial channels of trade for competitive markets. Such tax shall not apply to forest products severed from land owned by this Commonwealth and used by state educational institutions for experimentation in and teaching of forestry where severance is necessary for or incidental to such experimentation and teaching.