Analysis found no statistical differences in crop emergence between either the conventionally tilled or no-till subplots or among the four weed control treatments. There was a significant interaction between crop and tillage practice and crop and weed control for both the amount of weed biomass and crop yield. However, for all three crops the response pattern in both weed biomass and crop yield were similar across tillage practices (Figs. 3, 4, and 5). There were no significant interactions between tillage practice and weed control for either weed biomass or crop yield, nor was there a three way interaction between crop, tillage practice, and weed control. For all three crops, there was a significant difference in the amount of weed biomass between the conventional tillage and no-till treatments (Figs. 3, 4, and 5). In all cases, the amount of weed biomass was greater in the conventional tilled plots. This was due to the effect of the cover crop in suppressing weed germination (data not shown). The number of germinating weed seedlings were consistently lower in the no-till plots where the rye cover crop was planted. Flaming did not reduce the number of germinating weed seedlings when compared to the non-flamed plots. In all three crops, there was a significant difference in weed biomass among the four weed control treatments (Figs. 3, 4, and 5). Hand weeding had the lowest weed biomass followed by flaming which had significantly less weed biomass than the cultivated plots. The no weed control plots always had the highest amount of weed biomass in these fields. There were no significant differences in grain or lint yield between the conventional or no-till treatments regardless of the crop planted (Figs. 3, 4, and 5). However, crop yields tended to be higher in the no-till plots. In all three crops, there were significant differences among the four weed control treatments for grain or lint yield. In all cases, the no weed control treatment had the lowest grain or lint yields. While grain yields for both the popcorn and soybean did not significantly differ between the flaming and cultivation treatments, yields were always higher in the flame weeded plots. There was a significant difference in lint yields between the flame and cultivation treatments. The flame weeded plots had higher lint yields than the plots that were cultivated. In all cases, the hand weeded plots had significantly higher grain or lint yields. Our trials showed that for burn down application you need to use maximum gas pressure at speeds of less than 2 mph to be effective. This Estates to a cost of $14.11 or more (Tables 1 and 2). For row crop weeding, pressures of 18 to 20 lbs. per sq. in. at speeds of 4 to 6 mph gave the best results. This means that costs ranged from $4.00 down to $2.08 depending on the pressure-speed combination selected.
