As for rice not putting on grain my guess would be you did what I did the 1st time I planted it. Not enough fert. use 500 lbs 5-10-10 or 250lbs 10-20-20 when you plant. Then when it gets 8 inches put 200lbs urea (45-0-0) or some other high N product that will give you 80-90 units of N. At the same time add 1-4 inches of water and keep water on it from then on. That water will really keep the weed out. (rice seed 75-100 lbs per acre) On the Chufa most years I plant about end of May ...Flood it mid Sept. hunt all 3 seasons and youth day, leave it flooded until March ,then drain it and let it draw turkeys in. WEEDS are the biggest problem , if it is not clean and weed free , it gives up.