Is Cotton wood safe to burn indoors?

No. Burning cottonwood or other softwoods indoors is dangerous and can cause a house fire. Softwoods, such as cottonwood, pine, and fir, burn at a much higher temperature and produce more creosote than hardwoods. This can cause the chimney to become blocked, which can lead to a house fire. Additionally, the smoke from softwoods contains more harmful pollutants, such as carbon monoxide and formaldehyde, than the smoke from hardwoods.