Koenders was the 1st common unit on the aeration market. Others jumped on the windmill aeration bandwagon. Newer units saw ways to improve on the original. This could explain the better performance in winter for you in Colorado. I realize you do not have access to electricity at your location. From what I can tell in the picture an electrical unit would provide a larger open area. Hopefully what you currently have will help reduce the winterkill. Update us in spring about your results this winter.

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