Cherry tree and Sour cherry tree

Cherry tree noun - Any of numerous trees and shrubs producing a small fleshy round fruit with a single hard stone; many also produce a valuable hardwood.

Sour cherry tree and cherry tree are semantically related. In some cases you can replace phrase "Sour cherry tree" with "Cherry tree", this phrases are similar.

Sour cherry tree noun - Rather small Eurasian tree producing red to black acid edible fruit.

Cherry tree and sour cherry tree are semantically related. You can use "Cherry tree" instead a noun phrase "Sour cherry tree".