Crop residue and fertilizer management effects on nutrient use and barley production

Abstract

Cereal straw has many potential on-farm and off-farm uses. If straw is to be removed from land, the practice should not adversely impact long-term crop production and soil quality. A 10-yr experiment was conducted on a Dark Grey Solod near Beaverlodge, Alberta (55°13′N, 119°20′W) to determine the effects of fertilizer and straw management on the yield of, and nutrient (N and P) use by, continuous barley (Hordeum vulgare L.). Four straw management treatments: (i) straw removal; (ii) straw ploughed in; (iii) straw disked in; and (iv) straw disked in plus a red clover (Trifoleum pratense L.) green manure disked in every fifth year, were superimposed on four fertilizer treatments. The fertilizer treatments were application of N and P: (i) banded at soil-test recommended rates (ST,b); (ii) broadcast and incorporated at soil-test recommended rates (ST,bi); (iii) banded at soil-test rates of N+ 25 kg ha−1 and P+ 10 kg ha−1 (ST+,b); and (iv) as in (iii) but broadcast-applied and incorporated (ST+,bi). The straw ploughed-in treatment tended to produce lower annual barley yield and N uptake (by 9 and 13%, respectively) than the other three residue treatments. Barley yield and utilization of N and P were unaffected by straw removal as compared to disking-in straw. Barley yield and N uptake were higher (by 12 and 17%, respectively) with N and P application at the higher rate. At the recommended rate, broadcast-and-incorporated application of fertilizers resulted in lower yields and nutrient use than banded-in application. Treatment effects on P uptake tended to be small. The green-manured treatment used less fertilizer N, resulted in less total barley grain production, and did not increase the amount of crop residues incorporated. It is concluded that grain yield and nutrient (N and P) use of a continuous barley cropping system, fertilized at recommended rates of N and P, were unaffected by straw removal. Key words: Crop residue management, continuous barley production, fertilizer N and P