The following is the results of your search for shittah-tree.
Shittah-tree: (Isaiah 41:19) (R.V., "acacia tree"). Shittah wood was employed in making
the various parts of the tabernacle in the wilderness, and must
therefore have been indigenous in the desert in which the Israelites
wandered. It was the acacia or mimosa (Acacia Nilotica and A. seyal).
"The wild acacia (Mimosa Nilotica), under the name of sunt,
everywhere represents the seneh, or senna, of the burning bush. A
slightly different form of the tree, equally common under the name of
seyal, is the ancient 'shittah,' or, as more usually expressed in
the plural form, the 'shittim,' of which the tabernacle was made."
Stanley's Sinai, etc.