How many to use: Succah 34b, 35a
Identifying the "Aravah" species: Succah 33b
A mountain willow known as "Tzaftzefah": Succah 33b, 34a
A willow which grew on land which doesn't require irrigation: Succah 33b
An Aravah which is also known by a joint-name: Succah 34a
Minimum size of the Aravah: Succah 32b
A dried-out Aravah: Succah 33b
An over-ripe Aravah: Succah 33b
If the top is clipped: Succah 33b
If the leaves are separated/splayed: Succah 33b
If some of the leaves have fallen off: Succah 33b