I am looking for some help identifying a fungus growing around the base of a fruitless mulberry I have in my yard in the Los Angeles CA area. The fungus has been growing (elongating) for quite some time now. The new growth starts off whitish in appearance and then gradually turns brown and "knotty". Any ideas on what this might be. Can it be dangerous to pets or people?? I will attach some photos, if I can figure out how. Thanks.