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Challenges and Opportunities for Continuous No Till Systems. Brian Jones January 13, 2009. Continuous No Till. Long-term systems approach that keeps soil covered with residue, reduces soil disturbance to zero and maximizes number of days with living roots in the soil. Why?.
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Challenges and Opportunities for Continuous No Till Systems Brian Jones January 13, 2009
Continuous No Till Long-term systems approach that keeps soil covered with residue, reduces soil disturbance to zero and maximizes number of days with living roots in the soil.
Why? Long term this is the best management decision our growers can make to become more profitable! • Can we stay in business when inputs go up? • Do commodities go up too? • Can we face public that increasingly demands “environmental sustainability”? • Not with current public perception • No control of markets, inputs, public perception • Control of cropping systems, soil loss, soil cover
Why? Long term this is the best management decision our growers can make to become more profitable! • Get our growers away from short-term, and highly variable, profits • This system requires commitment but offers long-term stable profits
No-Till in the U.S. (1994-2007) 23% of Cropland in US Only 6-12% CNT (5 yrs) (CTIC, 2007)
No-Till in the U.S. (1994-2007) “Rotational tillage” • No-till used but… • Full width tillage somewhere in system • Road to nowhere • Never reach maturity • Four phases: • Initialization • Transition • Consolidation • Maintenance 23% of Cropland in US Only 6-12% CNT (5 yrs) (CTIC, 2007)
Soil structure improves Microbial activity increases Requires additional N OM increase requires fuel “Spend N to make N” Phase 3 Consolidation Phase 4 Maintenance Phase 2 Transition • Continuous flow of N and C • Maximum availability of soil water • More P available • Huge below ground biomass • Most forgiving to traffic • C accumulates • Soil WHC increases • More N mineralization and immobilization • Increase in CEC • Increase in nutrient cycling • Depend on climate and soils • OM accumulates • Aggregation improves • Microbial activity elevates • P accumulates • Increase N immobilization and mineralization 20 + 11 to 20 5 to 10 Phase 1 Initialization 0 to 5 Time (years)
No Quick Fix • Most challenges occur in initialization phase (years 0 – 5) • Have to provide good information for growers to get through • Tillage is the “quick fix”… but not really • Most challenges will be answered by the system
Pest Mgt Equipment Crop Rotations CULTURAL BIOLOGICAL NO-TILL Residue Mgt Cover Crops Nutrient Mgt Soil Health ENVIRONMENTAL
How do I deal with all that residue? Starts at the combine Even distribution SOLUTION CHALLENGE
Poorly Managed Residue • Hair-pinning • Poor soil/seed contact • Poor depth control • Poor emergence
How do I deal with all that residue? Starts at the combine Even distribution Tillage cannot redistribute Consider planter attachments SOLUTION CHALLENGE
Planter Attachments for Residue • Row cleaners • Should just skim surface • Different kinds for different residues • Will also help warm soils
Planter Attachments for Residue • Coulters • Sharp • Cut through residue
Planter Attachments for Residue • Closing wheels • Depends on soil type and preference • Must avoid sidewall compaction • May change as soil changes
I can’t rotate, I need all the feed I grow. Rotation even more important in CNT Relying on soil to work for us In continuous silage systems (corn/rye) Alfalfa or soybean ideal No-till even more critical SOLUTION CHALLENGE
Importance of Rotation in No-Till • Stimulate biological activity • Crucial to have abundance of soil organisms • Bacteria, fungi, mycorrhizae, arthropods, earthworms, plant roots • Need a balanced diet • C:N rotation • Root systems
Can’t Rotate? • Manure will help stimulate soil biology • Transition time will be slower • Be more alert for insect and disease pressure (two grass crops)
My weed control program is not working like it used to. Weed populations will shift towards perennials and biennials SOLUTION CHALLENGE
Weed Control • Requires different approach • Chemical seedbed preparation • Careful herbicide selection/application • Need to use crop protection technology • Roundup Ready • Optimum GAT • Crop rotation
I can’t control the slugs, and slug bait is too expensive. Slugs are not well understood Thrive in moist soil with high OM, i.e. a good CNT field SOLUTION CHALLENGE
Slugs #1 CNT Pest • Prefer cool and wet conditions • Have seen them in July – Sept under residue • Research underway to understand preferential feeding
General Slug Recommendations • Get plants up fast • Plant at higher soil temp • Use starter • Use row cleaners • Warm soil up • Move residue • Metaldehyde (slug bait) does work • Broadcast or maybe band apply?
I have to till because of compaction. Easy answer: stay off when wet… Not realistic Custom operators Compaction increases with soil wetness, and wet soils transmit compaction deeper “Addicted to Tillage” SOLUTION CHALLENGE
Change Management With Time • Phase 1 (0 – 5 years) • Limit axle load to 10 tons, use flotation tires • Use vertical tillage only when soil is dry • Maintain residue cover • Phase 2 and beyond (20+ years) • OM and porosity provide a firm soil matrix for air and water movement • Better supports traffic without compression (think sponge) • Aerator may relieve any surface compaction (low angle)
How will my fertilizer program change? Principles of fertility do not change May need more N in Phase 1 Will equilibrate over time SOLUTION CHALLENGE
Soil N Conserved with CNT • Samples collected from 63 sites in coastal plain (sandy soils) • No-till from 0 to 14 yrs • CNT conserved 20 lb N / acre / year (Spargo et al., 2008)
No-Till Fertility Considerations • Soil OM increases • High CEC = lower nutrient requirements in long-term systems • Less sediment loss = less nutrient loss • OM is 2% N; @ 10 T/acre soil loss = 20lb/A N • P and K bound to soil particles • Cooler soil with no-till will slow root growth, fertilizer placement important
Nutrient Stratification…No Problem 12-year average corn yields in Missouri
It costs too much to grow cover crops. Costs too much not to grow cover crops! “Close the loop” in the whole system SOLUTION CHALLENGE
Value of Cover Crops in 2006 Corn Silage AS MUCH AS $250.00 PER ACRE GREATER PROFIT BY USING COVER CROP IN 2006!!
Take Home Points • Will not have successful continuous no-till without using the whole system • Challenges will decrease with the length of the system
We (advisors) must have answers to grower’s questions as they face these challenges • Formation of the Virginia No-Tillage Alliance organization
Mission Statement: “The Virginia No-Tillage Alliance exists to maximize farm productivity and profitability by promoting the successful implementation of no-till practices through shared ideas, technology, conservation and education.” • Encourage your membership and participation • Conference on February 4th • Vendors welcome at no charge What is VANTAGE? The Virginia No-Tillage Alliance (VANTAGE) is a group of farmers, agribusinesses and local agricultural government organizations that are using no-till systems in their operations or are advising others about these systems.
THANKS QUESTIONS?