Water soluble anionic polyacrylamide (PAM) is a highly effective erosion deterrent in furrow irrigation, but little
is known about the effect of plant residue on PAM efficacy. We hypothesized that increasing plant residue in
irrigation furrows may decrease PAM's ability to control erosion. Treatments included furrows with 3.2 g and
10 g m-1 straw applications irrigated with PAM or untreated water, and conventionally irrigated furrows (no PAM
and no straw). Five irrigations were monitored on a field with 1.5% slope and silt loam soil (Durinodic Xeric
Haplocalcids). PAM was applied as a granular patch at the furrow inflow end (33 g or 1 kg active ingredient ha-').
Irrigation inflows of 23 L min' were cutback to 15 after runoff began. Adding more straw, or adding PAM to straw-treated
furrows decreased furrow sediment loss and increased net infiltration, but only for the first two irrigations
after treatment. For fresh furrows, straw treatments reduced sediment loss an average of 86% and straw + PAM
reduced sediment loss nearly 100%, compared to conventionally irrigated furrows. High-straw+PAM and lowstraw+PAM treatments produced the same furrow sediment losses and net infiltration amounts, i.e. increasing plant
residues in furrows did not decrease PAM's efficacy on these soils
