Orlah 2:3-4

Orlah 2:3

Orlah can nullify mixed species, mixed species can nullify orlah, and orlah can nullify orlah as follows: If a seah of orlah fell into 200 seah of regular produce, then just over a seah of orlah or of mixed species fell in, then the orlah nullifies the mixed species, the mixed species nullify the orlah, and the orlah nullifies the other orlah.

Orlah 2:4

The preceding ratios that nullify do not apply to anything that causes dough to ferment, that flavors a dish, or that creates meduma (a forbidden mixture) when combined with terumah, orlah or mixed species (because things that leaven and season food are stronger). Beis Shammai say they also transmit ritual impurity (if the spices in question are themselves ritually unclean). Beis Hillel says that they only transmit impurity in the volume of an egg.