quiet
11-16-2004, 10:20 PM
Summaries from Iowa State's Research on CGM:
1999 Corn Gluten Meal/Urea Crabgrass Control Study - Year 2
The 2000 growing season was quite warm and dry with above-average temperatures and below-average rainfall from April through September. Supplemental irrigation was required throughout the season to keep the bluegrass in good condition.
In early May, bluegrass quality was improved on grass treated with urea. Response to CGM treatment was slower but the quality of urea and CGM treated turf was similar through June and better than the untreated control. As expected, quality improved following the sequential treatments of CGM and urea in July and August. By September, the high temperatures and below-normal rainfall caused the bluegrass to enter dormancy. Rainfall and moderate temperatures in October caused a late season greenup and on October 27, grass treated with CGM or urea on September 5 (Treatments 2 and 4) had significantly better quality than grass not receiving treatments on that date. Mean data for the entire season show that all CGM and urea-treated grass had better quality than untreated.
There were no statistically significant differences in weed populations between the treated and untreated bluegrass. Crabgrass populations were low in all plots (Table 2). There were fewer crabgrass plants in untreated bluegrass than in treated because of increased competition from broadleaf weeds in the untreated grass. Dandelion populations were similar in treated and untreated bluegrass (Table 3). There were slight numerical differences but none were statistically different. Percentage clover cover also was similar in the treated and untreated bluegrass (Table 4). Through August 29, clover cover was numerically greater in bluegrass treated with CGM and urea in split applications of 2 lb/1000 ft2 than in the untreated controls.
1991 Corn Gluten Meal Crabgrass Control Study - Year 10
Spring 2000 was quite warm and dry with above-average temperatures and below-average rainfall. At spring greenup in April, there were slight quality differences between treated and untreated turf but by mid-May, the differences were quite distinct (Table 1). Quality differences between CGM-treated turf and untreated turf were significantly different for the entire season but on some dates, the quality of turf treated at various CGM levels was not different from the untreated control. By mid- to late-July, the quality of all treated and untreated turf began to deteriorate because of the lack of rainfall. Some rainfall improved turf quality by late August. Late season data from October 27 show a definite CGM effect in turf treated with CGM at 60 lb/1000 ft2 and above.
Treatment with CGM resulted in numeric reductions in crabgrass populations for the entire season but the differences were not statistically significant (Table 2). Mean crabgrass reductions for the entire season were „ 98% for all CGM rates except 20 lb/1000 ft2 (Table 2). In 1997 through 1999, crabgrass counts were higher in turf treated with 20 lb/1000 ft2 than in untreated turf. In 2000, crabgrass counts were higher in untreated turf and CGM at 20 lb/1000 ft2 provided a 63.3% reduction in crabgrass (Table 5). Reductions in crabgrass counts for 2000 were higher than in 1997, 1998, and 1999 at all other CGM levels.
Another study worth reading in it's entirety was done by UC-Davis.
http://ucce.ucdavis.edu/freeform/slosson/documents/1999-20002063.pdf
1999 Corn Gluten Meal/Urea Crabgrass Control Study - Year 2
The 2000 growing season was quite warm and dry with above-average temperatures and below-average rainfall from April through September. Supplemental irrigation was required throughout the season to keep the bluegrass in good condition.
In early May, bluegrass quality was improved on grass treated with urea. Response to CGM treatment was slower but the quality of urea and CGM treated turf was similar through June and better than the untreated control. As expected, quality improved following the sequential treatments of CGM and urea in July and August. By September, the high temperatures and below-normal rainfall caused the bluegrass to enter dormancy. Rainfall and moderate temperatures in October caused a late season greenup and on October 27, grass treated with CGM or urea on September 5 (Treatments 2 and 4) had significantly better quality than grass not receiving treatments on that date. Mean data for the entire season show that all CGM and urea-treated grass had better quality than untreated.
There were no statistically significant differences in weed populations between the treated and untreated bluegrass. Crabgrass populations were low in all plots (Table 2). There were fewer crabgrass plants in untreated bluegrass than in treated because of increased competition from broadleaf weeds in the untreated grass. Dandelion populations were similar in treated and untreated bluegrass (Table 3). There were slight numerical differences but none were statistically different. Percentage clover cover also was similar in the treated and untreated bluegrass (Table 4). Through August 29, clover cover was numerically greater in bluegrass treated with CGM and urea in split applications of 2 lb/1000 ft2 than in the untreated controls.
1991 Corn Gluten Meal Crabgrass Control Study - Year 10
Spring 2000 was quite warm and dry with above-average temperatures and below-average rainfall. At spring greenup in April, there were slight quality differences between treated and untreated turf but by mid-May, the differences were quite distinct (Table 1). Quality differences between CGM-treated turf and untreated turf were significantly different for the entire season but on some dates, the quality of turf treated at various CGM levels was not different from the untreated control. By mid- to late-July, the quality of all treated and untreated turf began to deteriorate because of the lack of rainfall. Some rainfall improved turf quality by late August. Late season data from October 27 show a definite CGM effect in turf treated with CGM at 60 lb/1000 ft2 and above.
Treatment with CGM resulted in numeric reductions in crabgrass populations for the entire season but the differences were not statistically significant (Table 2). Mean crabgrass reductions for the entire season were „ 98% for all CGM rates except 20 lb/1000 ft2 (Table 2). In 1997 through 1999, crabgrass counts were higher in turf treated with 20 lb/1000 ft2 than in untreated turf. In 2000, crabgrass counts were higher in untreated turf and CGM at 20 lb/1000 ft2 provided a 63.3% reduction in crabgrass (Table 5). Reductions in crabgrass counts for 2000 were higher than in 1997, 1998, and 1999 at all other CGM levels.
Another study worth reading in it's entirety was done by UC-Davis.
http://ucce.ucdavis.edu/freeform/slosson/documents/1999-20002063.pdf