In partial response to Young, tests with advanced numerical models are suggested for evaluation of net effects of seeding on precipitation in seeded and adjacent areas. Shower seeding in the U.S. plains cannot produce significant precipitation unless there is stimulation of the flow process that forms clouds. Several papers on cloud seeding projects in west Texas are discussed. These papers are thoughtfully developed, but some claimed effects are insignificant in magnitude, others are necessarily inconclusive at best, and important problems such as possible redistribution of natural rains by seeding are untreated in the papers and related experiments. If reasonable prudence is to attend use of resources, then future cloud seeding studies must be guided in part by advanced theoretical studies and all cloud seeding programs must be attended by carefully developed means to evaluate the results.

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