Onnia tomentosa (Prev. Inonotus tomentosus) “Wooly Velvet Polypore” Parasitic on conifers. This young wavy polypore can be mistaken for a toothed fungus when looking from above. Below the cap surface, however, there are pores and a dark brown short stipe. Onnia tomentosa causes a white root rot and is a formidable pathogen of cultivated white spruce plantations.