Runoff Weed Seed, Sediment, Infiltration and Weed Establishment as Affected by PAM in Furrow-Irrigated Corn
Table 2.   Seasonal Weed Plant Counts (weeds per two meters)
Treatments Kochia Lambsquarters Redroot Pigweed Hairy Nightshade Total
PAM Herbicide 1997 1998 1997 1998 1997 1998 1997 1998 1997 1998
Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD
No PAM Dual 11 18 1 2 18 5 17 4 6 5 8 3 6 5 24 29 40 14 50 35
Eradicane 10 8 6 10 26 8 27 1 9 3 16 3 9 16 76 96 55 23 125 94
None 4 2 5 5 32 11 38 16 20 14 24 14 14 9 98 138 71 6 165 158
Average 8 10 4 6 25 10 27 12 12 10 16 10 10 10 66 91 55 19 113 106
NRCS STD Dual 16 26 7 6 16 9 27 4 9 12 6 4 16 17 22 20 57 23 62 23
Eradicane 15 15 6 5 33 16 35 7 20 10 29 12 12 17 67 65 81 56 137 71
None 4 5 5 6 24 9 36 13 30 19 29 16 12 5 53 69 71 28 123 98
Average 12 16 6 5 25 13 33 18 20 15 21 15 13 12 47 53 70 35 107 70
Patch Dual 20 32 5 5 23 3 23 7 12 11 11 3 3 4 27 35 57 24 66 42
Eradicane 9 12 4 6 23 10 38 16 12 8 21 13 7 12 65 83 51 33 129 108
None 4 6 3 3 30 6 41 26 23 11 32 20 10 1 77 107 67 11 154 154
Average 11 18 4 4 25 7 34 18 16 10 21 15 7 7 57 74 59 22 116 104
Average Dual 16 23 4 4 19 6 23 6 9 9 8 3 8 11 25 25 52 20 60 30
Eradicane 11 11 5 6 27 11 34 10 14 8 22 10 10 13 69 72 62 37 130 80
None 4 4 4 4 29 8 38 17 25 14 29 15 12 5 76 96 70 15 147 122
Table 2.   Seasonal Weed Plant Counts

Generally, PAM-treated furrows had higher weed counts than non-treated furrows.  We believe this resulted from erosion washing away partially germinated seed in control furrows, whereas PAM-treated furrows, with stabilized soil, allowed germination and emergence to occur.  Weed counts were generally suppressed by herbicides as expected, although less so in 1998 which had a cool wet spring.  Mass of weeds (not shown) was greatly reduced in all instances by herbicides.
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[Title] [Abstract] [Approach] [Table 1] [Table 2] [Table 3] [Table 4] [Conclusions]