Hilchos Issurei Mizbeiach 5:4

Things that are not meant to be burned include the flesh of sin offerings and guilt offerings, the flesh of offerings of a lower degree of sanctity, the remains of the flour offering, the surplus of the omer or a bird sin offering, the showbread, the two loaves brought on Shavuos and the log of oil brought by a metzora (“leper”). If someone burned an olive-sized volume of any of these on the altar or its ramp along with leaven or honey, he is subject to the penalty of lashes. Even though none of these things is meant to be burned on the altar, since they are considered offerings, one would be liable for burning leaven or honey with them, as per Leviticus 2:12: “As a first-fruit offering you shall offer them to God.”

Hilchos Issurei Mizbeiach 5:5

It is likewise prohibited to offer on the altar any of those things we just named as not meant to be burned. According to our oral tradition, when there is something from which part is meant to be burned, it is prohibited to burn the rest of that thing.