Rotten Oak forest blend (this is sustainably harvested from our own property Cultured and produced by my husband (Mike) who has over 30 years experience in keeping & breeding wood eating insects and invertebrates such as millipedes, pill bugs, beetles, spring tails and roaches it is one of if not the most nutritious wood fibers there is. It also contains several kinds of wood mushrooms which have been shown to have great health benefits to insects and animals. We heat treat it to 120 degrees for several hours to kill off any random insect, fungus or bacteria's that may be harmful, this leaves behind a wonderful high protein wood fiber which is filled with a great variety of health benefits and nutrition for your bugs. we have used these same procedures for years to grow some on the largest and healthiest insects and inverts.