International Biochar Initiative IBI Technical Bulletin #102
Practical aspects of biochar application to tree crops
Biochar should always be tested for safety before applying to soil (see IBI Technical Bulletin #101: Quick tests to determine whether a biochar material contains compounds that are potentially harmful to plants). Biochar is not a single material and can vary in its composition according to how it was made and what it was made from. While IBI is aware of several tree planting projects using biochar, to our knowledge there have not been any research results published in the scientific literature in English on applying biochar to trees when establishing them. For this reason we are providing guidelines for experimenters to consider.