True or False: Red & Mississippi Rivers Deposit Silt in the Southwest for Farmland?

False.

The Facts

• Mississippi River deposits silt in the Mississippi Delta (southeastern Louisiana) — creating some of the world's richest alluvial soil.
• Red River (of the South) joins the Mississippi/Atchafalaya in Louisiana — also deposits in the Delta/Atchafalaya Basin.
• The Southwest (AZ, NM, OK, TX west of ~100th meridian) is not fed by these rivers. It's largely arid, relying on the Colorado River, Rio Grande, and groundwater.

Why the Confusion?

Perhaps mixing up "South" (Delta) with "Southwest." The Mississippi Delta is southeastern U.S. The Southwest is a distinct climatic/physiographic region.

Great farmland from these rivers? Yes—but in Louisiana, Arkansas, Mississippi, not Arizona or New Mexico.