Agricultural agencies sponsor winter cropland meeting for producers
Natural Resources Conservation Service (NRCS) District Conservationist Jennifer Hegge welcomed producers to the 2013 Winter Cropland Meeting at the Emmons County Courthouse in Linton on Thurs., Feb. 21.
The meeting was sponsored by the Emmons County Soil Conservation District (ECSCD), NDSU Extension Service and NRCS. Lunch was provided by the ECSCD and prepared by ECSCD Clerk Rhonda Vetsch.
On the agenda was Dr. Mark A. Liebig, Research Soil Scientist from USDAARS Northern Great Plains Research Laboratory (NGPRL) in Mandan.
Dr. Liebig has led a broad research program since 1999 at NGPRL focused on soil health and gas flux evaluations of crop, grazing lands, biofuel and integrated management systems. Based on that research, he found diverse crop rotations contributed to more stable crop yields and enhanced soil health as shown by higher soil organic matter, improved soil physical conditions and slower soil acidification.
“Native American tribes used cropping practices and rotations in river bottoms that were successful in adapting agriculture practices to our region,” Dr. Liebig said.
Following European settlement, experiments at NGPRL focused on providing information on crops that would grow well on fertile, but drought-prone prairie soils.
They found fixed sequencing limited their flexibility to address many challenges and opportunities that could lead to weed, insect and disease infestations over time. The dynamic cropping systems provided more flexibility and opportunities. Dynamic cropping systems better addressed long-term viability of yield stability and resilience and soil health.
“Soil management can serve as a cornerstone for ecological resilience, particularly during times of rapid change,” Dr. Liebig said.
“Looking to the future, we have some challenges,” Dr. Liebig said. “We need to produce food for a lot more people, we need to consider climate change effects and we need the dollars to support conservation from the private sector and the general public.”
Producing an adequate amount of food while protecting environmental quality and sustaining the economic well-being of rural communities represents a signifi- cant agricultural challenge. Liebig stressed there is an urgent need to develop crop management systems that are inherently resilient to external stressors, yet are highly productive, economically competitive and environmentally benign.
Augustin provides education to producers, technical service providers and others on current and emerging soil management practices. He reviewed the value of soil testing and interpreting plant tissue tests.
“When it comes to soil fertility management, it all starts with the soil test, knowing what you have so you can put down the right amount of fertilizer, and what you need to reach your yield goals,” Augustin said.
Two methods of doing that are central tendency and site specific. Central tendency is a field-by-field analysis, a composite of several readings that comes up with an average reading. Site-specific concentrates on a specific area in the field through grid sampling and zone sampling.
To gather data, especially for zone sampling, they focus on areas of similar crop production using yield monitoring, measuring electrical conductivity, and using remote imagery (aerial photos) to create fertility zones.
“It is important to take lots of photos and track information from that field to get a better idea of what is going on in that field with the different data that is put together,” Augustin said.
Soil surveys can also give some ideas of what the soil properties are but are not one hundred percent accurate.
When interpreting soil tests it is important to know what phosphorous test was used. This can greatly affect phosphorous application rates. Normally, the Olsen test is used in North Dakota labs.
Plant tissue analysis, a reflection of growing season up to the point of time of sampling, is a good process by showing how healthy the plant is the day they clip the plant. Procedures on how to do plant tissue analysis can be found at Agvise website www.agvise.com.
Augustin said soil testing can be sent to labs at NDSU Soil Science Department in Minot, Agvise in Northwood andAg Soil Science in Minot.
He said, regarding the timing of soil testing, it should be done every year, and it is also a good idea to use the same tester as the previous year for consistency.
“Generally people do it in the fall or the spring, and most start in October,” Augustin said. “What is important is that you be consistent as to when you do it each year.”
He said soil testing is one of the best things you can do in order to ensure what nutrients are in the ground.
NRCS District Conservationist Michelle Jezeski from Ellendale performed demonstrations on soil aggregate stability and soil slake.
On the soil aggregate stability demonstration, two soil samples were used from different management regimes. One sample was from an intensive tillage system, the other from an established no till system.
Initial observation of the aggregates (soil particles stuck together) showed several differences. The intensive tillage system aggregate had a platy appearance, no pore space or root matter. The no till aggregate had a cottage cheesy appearance, many pore spaces that varied in size and several roots.
On the slake test demonstration, both aggregates were placed on a screen and submerged in a jar of water. The purpose of the slake test was to show how a soil aggregate will respond to water, simulating what the soil will do during a rainfall event.
The intensive tillage aggregate collapsed and fell apart like a sugar cube does in hot coffee. All of the soil particles fell to the bottom of the jar. The no till aggregate maintained its structure. Very few particles fell to the bottom of the jar. Even as the aggregate soaked in water through lunch time, it still maintained the same structure and held together.
“The results of this are important because it shows how in different management systems, the soil will respond to rainfall,” Jezeski said.
Pore space is important for water and air exchange and they provide the streets and avenues that facilitate efficient root growth down through the soil profile. When aggregates collapse, they reduce or eliminate pore space and add to any existing compaction. When the pore space isn’t available for water and air exchange, the plant growth suffers. Plants must put more of their resources into root growth instead of seed production.
This all translates to reduced yields. In addition, surface applied fertilizers are not allowed to infiltrate into the root zone without pore space. If those fertilizers remain on the surface, they will not be taken up by the plant and will run off in the next rainfall event. Again, this translates to reduced yields, waste of money, and is detrimental to water quality.