Biochar is made from organic waste and has been used as a soil amelioration for centuries. Biochar can be manufactured through the process of pyrolysis. In this study, the guayule plant, grown in arid regions, was used to produce biochar via pyrolysis, specifically the guayule's bagasse. The guayule plant is used to make rubber and resin, however 90% of its product yield is bagasse, which is currently considered waste. This study focuses on utilizing the bagasse in the form of soil enhancement. Guayule bagasse derived biochar (GBDB) was analyzed in two different arid region soils from Pinal County, Arizona. The cation exchange capacity and pH were both measured for the soils with the addition of the GBDB as well as a control. Addition rates of the GBDB in both soils were 0%, 2%, 5%, 10%, and 20% by mass. The results show that the addition of 10% of GBDB to both soils had the highest CEC and the addition of 20% of GBDB to both soils had the highest pH. The increased CEC with GBDB indicates that GBDB can potentially enhance the soils' fertility, structure, and organic matter. Further studies should be done to lower the pH of the GBDB in order to be in pH range more suitable for growing crops. Utilizing GBDB as a soil enhancement can increase guayule's economic status as industrial material and be an alternative to more energy-dependent and environmentally harmful agricultural and industrial techniques.
