Trial Location: Fairview Research Farm NW-5-82-3-W6 on RR #35, MD of Fairview
Research Coordinator: Dr. Akim Omokanye
From: Peace Country Beef & Forage Association 2015 Annual Report
Usually we think of cover crops in terms of reducing soil erosion and adding organic matter to the soil – but they can do much more. Cover crops add organic matter but the amount really varies depending upon the cover crop species and the conditions under which it is grown. Some cover crops fix nitrogen thereby improving soil fertility but many more require nitrogen to grow. Some cover crop species may be a non-host for a pest or may release materials that are toxic to the targeted pest. Cover crops can help to reduce compaction and improve soil structure. The addition of the plant top and, especially root matter, helps to improve water infiltration and holding capacity. It can also decrease soil bulk density. Deep rooted cover crops can help to decrease the impact of soil compaction.
Methods
Eight cover crops were seeded in small plots in two replications at Fairview Research Farm (NW5-82-3W6) on RR #35. The site used was seeded to alfalfa and had been hayed for more than 10 years. Prior to seeding, soil tests at 0-6” soil depth done at Exova Laboratory (Edmonton) showed an OM of 3.0 % and a pH of 6.9. The site was sprayed with Roundup the fall before and worked in the spring before seeding.
The crops were seeded on May 25 at the following rates: Red Proso millet - 22.0 lbs/acre, Pearl millet - 22.0, Forage sorghum (Canadian Forage Sorghum Hybrid 30, CFSH 30) - 22.0 lbs/acre, Sorghum Sudan grass - 22.0 lbs/acre, Hairy vetch - 17.5 lbs/acre, Phacelia - 4.5 lbs/acre, Buckwheat - 25 lbs/acre and Hybrid brassica - 3.2 lbs/acre. The cereals (proso millet, CFSH 30, Sudan grass and pearl millet) were sprayed with 2,4-D Ester 700 at the recommended rate and plant growth stages. Other crops were not sprayed.
All crops were harvested on August 15 and samples taken for forage quality analysis. Red proso millet was harvested at the mid-dough stage and pearl millet was at 50% flowering stage. Both CFSH 30 and sorghum Sudan grass did not flower at all, so they were both harvested at the late vegetative stage (pre-boot stage). Hairy vetch was harvested at the early-pod stage. Composite forage samples were taken per crop, dried and later shipped to Central Testing Laboratory Ltd., Winnipeg, Manitoba for feed quality analysis using standard laboratory procedures for wet chemistry.
Results
Protein: The forage crude protein (CP) content was generally above 13% for all crops. The