A nut comes from a tree and so does sap.
fir
A nut comes from a tree.
Pod
Elm
elm
ElmOak
There isn't one that begins with an 'S' A three letter word for an evergreen tree is fir.
nut
Sap is the word your looking for.
seed
...
Yew (which is a kind of tree).
It could be rot.
The word appleseed basically means the seed that will eventually bear apples. This means that the word appleseed represents the seed of an apple tree or apple tree seed.
Seed is a four-letter word for pod from the word president since a seed pod is a type of pod.
A nut is a seed or fruit of a tree.
seed