Halvorson, M., R.R. Harwood, S.H. Halstead, and G.P. Robertson
Presented at the All Scientist Meeting (1996-07-16 to 1996-07-17 )
Long Term Ecological Research (LTER) at KBS was in its seventh cropping year in 1995. Four annual agronomic cropping systems, rotated into winter wheat from soybeans in a corn- (93) soybean (94) -wheat (95) rotation sequence. Agronomic annual cropping inputs for winter wheat was evaluated across six replicates on four different input systems. A perennial cropping system was also evaluated across six replicates for a second year alfalfa stand for yield in 1995.The annual cropping systems were planted to Chelsea winter wheat in mid-October using a John Deere no till drill in 1994. These treatments included conventional till (CT) wheat (Treatment 1) and no till (NT) wheat (Treatment 2) and had agronomic inputs applied based on best management practices (BMP). Based on soil tests taken late fall in 1994, 50 lb. N/A as ammonium nitrate (34-0-0), inorganic Nitrogen fertilizer application applied over the top in early spring using a Gandy Orbit Air Spreader and both treatments were sprayed with 2,4-D amine at a 1 pt/A rate for broadleaf weed control. A conventional broadcast sprayer was used to apply the herbicide treatment across six replicates of the conventional till and no till treatments.Two reduced agronomic input annual cropping systems were also evaluated. These were also planted to Chelsea winter wheat, however were treated with lower than BMP inputs levels. These included a Low Chemical Input wheat (Treatment 3), having a 30 lb. N/A as ammonium nitrate (34-0-0), inorganic Nitrogen fertilizer application. No herbicide application was done to this treatment in 1995. The Zero Chemical Input wheat (Treatment 4) did not have any herbicide or fertilizer applications in 1995 and is consistent with previous years treatments. Low Chemical Input (Treatment 3) and Zero Chemical Input (Treatment 4) wheat treatments were frost seeded to Mammoth Red Clover in mid-March and allowed to grow throughout the season as a cover crop to symbiotically fix nitrogen, increase organic matter (OM) levels, and increased soil structure properties. Mean yields for Chelsea wheat was 45.4 bu/A, averaged across all replicates and treatments in 1995.Treatments 1-3 did not yield significantly different from each other in 1995. Mean yields for TRT 1-3 was 49.6 bu/A. Treatment 4, the zero chemical input wheat had a mean yield of 32.6 bu/A. As expected, TRT 4 was significantly lower yielding than the other treatments.Agronomic Protocols and Yields can be viewed on the LTER World Wide Web Home Page: WWW: http://kbs.msu.edu/lter/home.html. Other information such as the LTER agronomic field logs and protocols from years 1989-1996 can also be accessed at this same home page address. In 1996, corn is in rotation in TRT 1-4 and two of four alfalfa cuts have been taken as of July 10.
Back to meeting | Show |