Week 17 or the second week of the Spring Semester was a very full week. It started on Monday with my driving to Grand Forks North Dakota for the Red River Basin Commission (RRBC) Annual Meeting and Conference, for work for three days. Then Thursday morning it was back to Fergus Falls for our class on grass based livestock systems. This week the lecture was on considerations for a sword , which is a stand of grass forbes, legumes and everything in it (the pasture). How it grows, what is in it nutritionally, how grazing can be used to either hurt sword health or improve sword health.
Have you ever wondered about how much pasture you need to feed a certain number of cattle (or other ruminant animals) or for that matter how much feed is available in a pasture. To answer these questions first you have to figure out how much to feed say 10 head of cattle that weigh 1000 lbs each. The feed requirement or feed ration is determined in lbs of DMI (Dry Matter Intake). This is the weight of the feed if all the moisture was removed. For a starting point you can assume the animals need about 3 to 3.5% of their body weight in feed then allow about another 1% for waste. So a good starting point is to assume 4%. So if you have 100 head of cattle at 1000 lbs each your herd weight would be 100,000 lbs. Herd weight times 4% equals 4,000 lbs of DMI is required a day for the herd (at least as a starting point). So the typical pasture has about 150 to 300 lbs of dry matter forage per inch of grass eaten per acre of pasture. To be conservative for this example we will assume 200 lbs-DM/ac-in. If you had an average of 9-inches of grass in your pasture you could allow the cattle to graze it to 4-inches without overgrazing the pasture, meaning you could graze 5-inches. 5-inches * 200 lbs-DM/ac-in equals 1,000 lbs-DM/acre of pasture. Therefore you would need 4,000 lbs DM/1,000 lbs DM/ac = 4 acres of pasture per day for your herd of 100 cattle weighing 1,000 lbs each.
Friday morning we were on the road at 5:00 am heading to Aberdeen South Dakota for the Northern Plains Sustainable Agriculture Annual Conference. http://npsas.org/ At the conference the SFP Program was responsible for two children's sessions. One involved song and dance and the other included planting seeds, seed saving and farm bingo. I don't know if the kids had fun, but we all head a blast.
In addition to the kids program we had the opportunity to attend several workshops. One of the ones that I attended and found very informative was "Developing a Vision for Herd Improvement" by Gearld Fry. Mr. Fry, now in his 80's, has spent his life learning about, researching and developing cattle genetics for beef and dairy cattle that thrive on grass. It was amazing what he could tell about what a bovine would produce for off-spring and product by simply observing the animal and conducting a few simple measurements (one of which was bull testicle circumference). Mr. Fry has written a couple books on the subject as well as a website called http://www.bovineengineering.com/ which is very informative.
Another workshop that I went to was "Regenerating our Resources" by Gabe Brown. Mr. Brown and his son Paul run a 5,000 ac farm/ranch by Bismark, North Dakota where they raise primarily corn, beans and cattle. Mr Browns talk(per the program) explained the foundation of soil health and its importance in all facets of production agriculture. It covered growing and finishing cattle on tame, native and cover crop pastures, calving on pasture and winter grazing. High stock density/mob grazing and rotational grazing were also discussed. Mr. Brown also went over some of the financial numbers they are obtaining building soil health through cover cropping, which in turn has allowed them to significantly reduce or eliminate most outside inputs like commercial fertilizer and herbicides. Gabe Brown's son Paul will be speaking in Perham, Minnesota on March 15, 2013 at a workshop on "Cover Crops for Soil Health and Farm Profitability" which is sponsored by the Minnesota Dairy Initiative, NRCS, Sustainable Farming Association and the Sustainable Food Production Program at M-State Fergus Falls. The program is geared towards producers and seating is limited to 60. The North Dakota Burleigh County Soil Conservation District website has more information on building soil health with cover crops and grazing http://www.bcscd.com/?id=23
