Project: MLMMI 01-01-15
Objective
To conduct an economic and financial evaluation of a forage/livestock system which utilizes hog manure as the fertility source in an environmentally sustainable manner.
To measure the economic impact of 2 different livestock/forage systems as compared to traditional grain production.
To demonstrate this system under conditions which are relevant to forage/livestock producers of the Eastern/Interlake Region and for other areas of Manitoba.
To monitor for any environmental concerns related to spreading of hog manure on forage crops
Performer
Adrian Grenier
Stuartburn Piney Ag. Development Assoc.
Details
Status: Completed
Started: 2001-09-01
Completed: 2005-12-12
Funding Partners: who have contributed to MLMMI in support of this project:
Manitoba Pork Council and industry groups - $75,000
Amount Funded: $75,000.00
Performer Funded: $245,670.00
Total Cost: $320,670.00
Activity
First Progress Report received March 14/02.
Second Progress Report received Sept. 16/02.
Third Progress Report received March 6/03.
Fourth Progress Report received Oct. 15/03.
Fifth Progress Report received on March 12, 2004.
Final Report due September 1, 2004.
Extension granted for Final Report to March 31, 2005.
Draft Final Report received on April 12, 2005.
Final Report received on December 12, 2005.
Summary
Manitoba has experienced dramatic growth in the hog industry. Hog production is also expanding from traditional grain-producing areas of the province into areas primarily involved in forage and cattle production, such as southeastern Manitoba and the Interlake. Some of the forage land that is currently used or destined for receiving hog manure in the future is considered sandy or coarse-textured soil. Such soils tend to have a higher risk of leaching of nutrients than finer textured soils. Currently, there is limited information regarding the agronomic and environmental impacts of the application of hog manure to forages grown on coarse-textured soils.
Studies were initiated near Zhoda, MB, to determine the impact of the timing and rate of hog manure applied to forage grown on coarse textured soils with high water tables. Precipitation and soil groundwater data were also collected. In Experiment 1, manure treatments equivalent to 0, 60, 90, 120 lb N ac-1 were applied commencing in the summer of 2002 in summer and fall after forage harvesting; a treatment consisting of a split application of manure equivalent to 120 lb N ac-1 was also applied (60 lb ac-1 each in summer and fall). Four replicates were arranged in a completely randomized design. In Experiment 2, manure was applied at rates equivalent to 0, 100, 200, 300, and 400 lb N ac-1 in spring 2004 in three replicates in a strip plot design. Besides forage yield and quality, the distribution of nitrate- N and phosphorous in the soil profile was also monitored in both experiments.
In Experiment 1, evidence of nutrient leaching downward in the soil profile was minimal. Depending on conditions during the growing season and subsequent to manure application, N losses may have accounted for a considerable share of the N that was initially applied. Given the poor soil fertility at the site, strong yield response to applied manure was also likely a contributing factor to minimizing nutrient leaching. The evidence suggests that forages indeed are a strong candidate for manure application, especially in circumstances where inherent soil fertility is poor. Evidence of nutrient leaching was more compelling in Experiment 2. There was strong evidence of nutrient leaching downward in the soil profile for the 300N and 400N treatments. At the last sampling date, there was considerably more nitrate-N at depth in the soil profile for the 400N treatment compared to the other treatments applied. In both experiments, residual soil nutrient levels were low to very low, although there was evidence of K accumulation in both experiments as manure application rate increased. Residual soil N levels met the regulations set out by the Manitoba Manure and Mortalities Management Regulations, and were low to very low for nitrogen, phosphorous, and potassium basis the Manitoba Soil Fertility Guide. However, the evidence of nutrient leaching in Experiment 2 during the growing season indicates a real threat of downward movement of nitrate-N where application rates are excessive relative to crop demand.
Forages responded strongly to manure application with respect to nutrient uptake, nutrient content, and dry matter yield. In Experiment 1, dry matter yields increased considerably as manure application rate increased, as did nutrient uptake. The impact on forage nutrient content was less consistent across harvests, although as expected there was a trend in most instances of increasing nutrient content with increasing manure application rate. Fall-applied manure appeared to produce higher forage yields, possibly as a result of greater nutrient losses in summer-applied treatments as well as the lack of nutrient response when dry conditions prevailed during the summer period. Split N application was no more effective at increasing forage productivity than the 120N treatment when considering productivity over a production cycle (i.e. fall and summer harvest). Tming of nutrient availability is a key consideration in attempting to maximize forage productivity. In Experiment 2, for example, it was clear that nutrient availability was delayed somewhat relative to application date, as indicated by a delay in the accumulation of nitrate-N in the upper soil profile. Given the lack of leaching observed in Experiment 1 (up to target N rate of 120 lb ac-1), increasing manure application rates may be feasible relative to current recommendations. Splitting manure application rates may also provide another means of increasing manure application rates without causing adverse effects to the environment.