Fig. 6. Effects of time-of-incorporation and irrigation on the N remaining in barley straw over 320 d of decay.AI = autumn incorporated, SI = spring incorporated, Irr = summer irrigated, NIrr = nonirrigated. Symbols represent means (n = 6) of SIR expressed on an ash-free dry weight (AFDW) basis. Error bars are least significant differences (LSD) (P = 0.05, d.f. = 15) for within date comparisons.