Answer: Most mesquite trees sold are deciduous, dropping their leaves in fall and releafing when temperatures warm in late February/early March. (Native Americans used the tree releafing as a signal to plant crops.) Prosopis alba or Argentine mesquite is nearly evergreen, but it will also shed old leaves as new ones appear. It is not sold as commonly as P. chilensis or Chilean mesquite. Since your tree is so young, it may have dropped its leaves earlier due to transplant shock.
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