You may have seen the mystery seeds from last week when you pitted an olive. The ones in the photo were lying on the ground under an olive tree, Olea europaea.

Olive trees are originally from the Mediterranean region, where much of the world’s olive oil production still occurs. In the United States, olives grow in California and Arizona.

Olives are small trees, sometimes with multiple trunks.

The trunks of older trees are often gnarled and twisted, giving the trees and interesting look.

The leaves are a lovely greyish-green.

The flowers are greenish-white and are pretty much inconspicuous. Olive pollen is a known allergen. Here in Arizona a sterile variety of olive (that doesn’t produce pollen) has been developed for those who simply want to use the tree for ornamental purposes.

The fruit of the olive is green to red at first…

Over time the fruit turn black and drop off the tree.

Many newcomers to Arizona see the olive fruit and wonder if they can eat them, but olives straight from the tree are not edible. The fruit needs to be leached in salt and vinegar and then processed before it is good to eat. Or the fruit can be processed into oil.

You can grow olives from the pits, but of course the new plants won’t necessarily resemble the parent tree. Botanists have tricks to weaken the hard pit and increase the chance of germination, such as gently cracking the surface.

All this talk about olives has made me hungry. Maybe it is time for an egg salad sandwich with olives.

Do you have a favorite way to eat olives?