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. Comparisons of the wind direction-partitioned 69 EUs with all available 98 EUs revealed that basically all the seeding signal was contained within the 69 EUs where targeting was highly likely. The same partition excluded northwest flow EUs which were expected to transport seeding plumes south of the target gauges. . A dual partition used the same wind direction partition combined with exclusion of the larger 20% of natural precipitation amounts observed at the crosswind control gauge. Overall results were encouraging, suggesting that real seeding effects were particularly detectable when natural snowfalls were no more than moderate. . Results were presented for several other single and dual partitions, the latter always including the southwest quadrant winds at the seeding site. These results were mixed, ranging from strongly suggestive to somewhat suggestive to inconclusive depending upon the particular partition, gauge, statistical test, and number of experimental units available. A number of partitions provided interesting suggestions but none of the results were as convincing as the wind direction partition or entire population testing. . There were suggestions that seeding may have been more effective when SL W cloud (icing) was detected, when seeding plume temperatures were warmer and when wind speeds were lighter. But all of these interesting but mostly inconclusive suggestions would require a larger sample size than available for rigorous testing. Funding was not available for an experiment longer than a single winter, or for one with a larger target area including the more downwind portions of the plateau. The main reason for using propane seeding is to treat mildly supercooled cloud, too warm for effective AgI seeding. The frequency of such cloud over Colorado's mountains is discussed in Secs 2 and 5 and Appendix A, and the topic is briefly covered below. However, there are other good reasons for consideration of propane seeding as an adjunct or replacement for ground-based AgI seeding. Propane dispensers are relatively simple devices, significantly less complex than remote-controlled AgI generators which must use corrosive solutions. This makes them more amenable for fully automatic deployment. Consequently, propane dispensers are significantly more reliable and less expensive. Few remote-controlled AgI generators have been capable of monitoring the relatively low flow rates of AgI in solution as this is an expensive option. A number of cases have been documented where the remote generator was believed to be producing AgI smoke but where no AgI was detected. Silver iodide generators capable of monitoring solution flow rates have recently been fielded in the Snowy Mountains of Australia and are planned for a State of Wyoming program to begin during the 2005/06 winter. The authors consider it essential that any remote-controlled AgI generator provide positive evidence of both solution flow rate and flame temperature to insure that seeding is actually occurring. Personal communications with people familiar with these newer generators have suggested their purchase price is at least a factor of two higher than propane dispensers, and probably the factor is much higher for the Snowy Mountain generators. The reliability of these newer and more expensive generators has yet to be demonstrated. The authors' considerable experience with propane dispensers indicates that they are highly reliable, and both propane flow rate and temperature downstream of the expansion nozzle can easily be monitored. Cloud temperatures in the SL W zone over windward slopes and crestlines have largely been based on mountain-top measurements. For example, Boe and Super (1986) noted that the greatest 24