The sycamore (Ficus sycomorus) is a type of tree growing only in the Jordan Valley and near the Mediterranean coast. The sycamore is pictured as growing in abundance in the shephelah (lowland, 1 Kings 10:27). This is in contrast to cedars which Solomon planted in Jerusalem.
The sycamore is not the same as the tree by that name that grows in North America. The sycamore tree belongs to the nettle family, like the mulberry and fig trees. The fruit looks like a fig, but the taste is unpleasant. It is eaten by the poor. See Fauna and Flora of the Bible, 179-81.
Zaccheus climbed up into a sycamore tree at Jericho (Luke 19:4). Here is a sycamore tree at Ashkelon that reminded me of Zacchaeus. The limbs are low. Even a child could climb into the tree to get a better view.
Amos the prophet, who lived at Tekoah on the edge of the Judean wilderness, spoke of working with the sycamore fruit.
Amos replied to Amaziah, “I was not a prophet by profession. No, I was a herdsman who also took care of sycamore fig trees. (Amos 7:14, NET Bible).
This photo shows the sycamore figs on the tree.