This data publication contains the results from 45 experimental burns and 48 smoldering tests on masticated materials from mixed-conifer forests. These data were collected from 15 study locations from 2012 through 2016 as part of the MASTIDON project. The MASTIDON project was a four-year study to describe the phyical characteristics of masticated materials that were treated with four different cutting heads in xeric and mesic environments. The main focus of the project was to evaluate how leaving the particles on the ground for varying lengths of time affected the burnability of the particles. The project was funded by the Joint Fire Sciences Program (JFSP) and RMRS between 2013 and 2016. The masticated particles were created by four different machines, including a vertical rotating head, horizontal drum, chipper, and mower. They had been decomposing in situ in wet and dry areas of Idaho, and dry areas of Colorado, New Mexico, and South Dakota since their initial treatment and were between 0 and 10 years old. The materials were burned at the RMRS Missoula Fire Sciences lab, Missoula, MT. The experimental burns were conducted in a combustion facility on a large fuel bed 0.68 square meters in size. The smoldering tests were conducted on beds 497 square centimeters in size under a fume hood in the soils laboratory. This download includes (1) data on fire behavior within the experimental burns, including rate of spread, flame height, flame duration, consumption, heat flux, moisture content, and more; (2) temperature data, burn durations, duff moistures and thicknesses from the smoldering tests; (3) photos of the experimental burn beds and smoldering beds; and (4) files describing the MASTIDON project and its goals.