Maintaining water 18-24 inches deep in paddies during the winter controls invasive weeds and discourages waterfowl that eat wild rice seed. On heavy soils, this amount of water is enough to sustain the crop and provide for evaporation from the paddy. A supplemental water supply from wells or ponds is good insurance against weather extremes or problems with dikes. Wild rice will not grow in water that has a high salt level. Conventional wisdom indicates that wild rice seed must be held at a moisture content greater than 28 percent or germination will be significantly reduced.
Seed also requires three to four months of chilling to break seed dormancy and allow germination.
Contrary to conventional wisdom, shattered seed that has been allowed to completely dry in the fall in western Oregon fields has still produced thick rice stands the following spring. This observation and subsequent trials have confirmed that wild rice can be dried without killing the seed. Dry seed can be broadcast and harrowed into a field before fall rains fill the paddy. With this seeding method, seed dormancy is broken by chilling in the field without the added cost and problems of cold storage. Successful trials have been carried out in commercial paddies using this technique for three years.