Finding fruit trees in the wild can be a little challenging, unless they happen to be in their flowering phase. Since they are essentially just a different kind of tree, spotting them in a forest can be hard. They do however use different leaf block patterns and colours when compared to regular trees. The best signature for a fruit tree however is their trunk, since it is noticeably slimmer then the full block trunk of a regular tree.
Fruit trees can be hard to spot in the middle of other trees
The stem of a fruit tree is slimmer then a full block
Flowering fruit trees are easy to spot, however fruiting or ripe ones may be similar to their plain look
Fruit trees in various growing and seasonal stages - they are easily spotted on the map, however the cross shapes may be covered by other trees in a forest.