Identify trees online for free

Tree Identification

Does the plant have few scale-like leaves or no leaves, just thick fleshy green branches and stems that are ribbed and covered with spines? The fruit is a large red berry. 

CLUE: the tree is a cactus.

It is a saguaro.

- OR -

Does the tree have many leaves that are scale-like or awl-shaped? Fruit not as above.