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  1. CROP PRODUCTION Unit 7: Tillage & Seeding
  2. Tillage & Seeding (149)  Tillage – manual or mechanical soil stirring actions  Tillage Systems – type and sequence of tillage operations used for proper establishment and growth of crops
  3. Goals & Purposes (149)  Seedbed Preparation – provide optimum environment for seed germination and subsequent growth – Temperature – Moisture – Aeration – Seed-to-soil contact  Incorporating and mixing – crop residues, lime, fertilizers, and/or pesticides  Weed control  Conservation of soil & water – prevent erosion conserve precipitation, and improve infiltration
  4. Tillage Vocabulary (150)  Primary Tillage – inverts or shatters soil 6-14 inches deep; leaves the soil rough – Loosen and aerate surface layer – Incorporate fertilizer – Cover plant residue  Secondary Tillage – follow primary tillage; depth is 2-6 inches deep – Prepare final seed bed – Level and firm soil – Pulverizing soil for seed-to-soil contact – Control weeds
  5. Tillage Vocabulary (150) Tillage Implements – vary widely among engineers, agronomists, manufacturers, and producers Compaction – soil has few or no pore spaces, creating a poor environment for plant roots; measured with a penetrometer (on right)
  6. Primary Tillage Implements  V-ripper  disk plow  disk ripper  sweep plow  lister/bedder  moldboard plow  powered rotary tiller  chisel plow—combo
  7. Secondary Tillage Implements  disk harrow  roller packer  field cultivator  spring- spike- & tine-tooth harrows  seed bed finisher  row-crop cultivator
  8. Tillage Systems (156) – Conventional tillage: normal primary and secondary operations – varies from region to region – Clean tillage: leave little or no residue on soil surface – Mulch tillage: leave residue to reduce soil/water loss – Conservation tillage: leave >30% residue cover on soil surface – Minimum tillage: systems that employ the least amount of tillage required
  9. Tillage Systems (Con’t) (156) – Reduced tillage: utilize fewer or less energy intensive operations – Full-width tillage: tillage of entire field surface – Strip tillage: tillage of strips, leaving undisturbed strips – No-till: seed planted directly into previously undisturbed soil – Ridge tillage: ridges/furrows established & maintained throughout the year
  10. Tillage Methods (156)  Clean, full-width tillage systems – Conventional tillage – Plow and combined secondary tillage – Plow and strip-till planting – Plow, listing, and planting – Other clean, full width tillage systems
  11. Tillage Methods (159)  Conservation tillage systems – Full width conservation tillage • Chisel plow systems • Disk (and/or field cultivating) and plant • Sweep tillage – Strip till conservation tillage • Lister-planting • Strip rotary tillage • Till-plant – No till
  12. Tillage Operations for Special Situations (164)  Sub-soiling: used to break up impervious layers which limit root growth and nutrient and water holding capacities of the soil – Depths greater than 13-14 inches  Extremely deep primary tillage: as deep as four feet; turn up soil that has been buried
  13. Tillage for Weed Control (165)  Tillage before planting – as weeds germinate and begin growth  Tillage after planting and before crop emergence is completed – both weed control and breaking soil crusts  Cultivation after crop emergence – most economical and surest method for weed control
  14. General Considerations (166)  Agronomic aspects in adopting tillage systems: – Soil and climatic factors – more crop residues = lower soil temps and higher OM levels – Seed and fertilizer placement – heavy residues interfere with seed placement, covering seed with soil and seed-to-soil contact; fertilizer may be highly unavailable – Pest control – reduced tillage systems allow weeds seeds to remain near surface – Soil conservation – erosion directly linked to surface residue  Economic aspects in adopting tillage systems – primary consideration is net profit over long period of time
  15. Objectives of Seeding (169)  Proper depth placement – large seeds have large food reserves and longer hypocotyl/mesocotyl; in some soils, moisture is unavailable at shallow depths  Good seed-to-soil contact – proper planting procedure and equipment; proper tillage; avoid “crusting”  Proper rate and distribution – germination and purity; competitive ability; other environmental factors: canopy, tillering, competition w/other species
  16. Objectives of Seeding (172)  Time of planting – late planting can lead to lower yield  Row fertilizer placement – side-band, split boot, and pop-up
  17. Manual Planting (173) Problems: – Uneven depth – Uneven spacing – Uneven covering of seed – Excessive soil compaction
  18. Mechanized Planting (173) Row-crop planters – drill patterns, hill-drop pattern, check row pattern Grain drills Broadcast seeders – disadvantages such as uneven distribution/spacing, poor soil contact, requires higher seeding rates Specialized planters – potato planters, vegetable seed planters, and tobacco planters
  19.  Website resouces: – e.htm – –  Chapter 7 – Review Questions (p. 182-184) – Thinker