Soil Cultivation and Tillage

What is Tillage? The practice of keeping the soil mellow (soft) and free from weeds mechanically (physically). The practice of keeping the soil mellow (soft) and free from weeds mechanically (physically). Can be seedbed preparation or post emergence cultivation. Can be seedbed preparation or post emergence cultivation.

What are the purposes of tillage? 1) Develop soil tilth (physical condition of the soil) 1) Develop soil tilth (physical condition of the soil) 2) Kill weeds 2) Kill weeds 3) Manage crop residue 3) Manage crop residue

What is a seedbed? Place where seeds germinate & nourish young plants. Place where seeds germinate & nourish young plants.

Characteristics of a good seedbed?  Must be firm to allow seed to come in contact with soil particles to absorb moisture.  Must be porous to allow air to move, root development, water movement.  Water will not easily penetrate hard soil to get to roots.

Different Seedbed Characteristics… If soil is too loose, rain will wash away young plants. If soil is too loose, rain will wash away young plants. Some soils have excess water. Some soils have excess water. Oxygen is needed by roots so a compacted seedbed is not good. Oxygen is needed by roots so a compacted seedbed is not good. Air and water conduct heat more rapidly than soil, looser soils warm up sooner. Air and water conduct heat more rapidly than soil, looser soils warm up sooner. Plant residue on surface insulates, warms up slower. Plant residue on surface insulates, warms up slower. Residue provides a buffer against wind. Residue provides a buffer against wind.

RESIDUE ON A FIELD…

Soil Tilth   The condition of a piece of tilled land, in terms of its cultivation history and suitability for crops.   The degree of fineness of soil particles in the topmost soil layer.

How is good soil tilth developed? Till at proper time to maintain proper aggregation. Till at proper time to maintain proper aggregation. Too wet during tillage makes soil lumpy, too dry during tillage makes soil too fine and likely to be at risk for wind erosion. Too wet during tillage makes soil lumpy, too dry during tillage makes soil too fine and likely to be at risk for wind erosion. Over tillage will destroy soil structure and lead to soil compaction. Over tillage will destroy soil structure and lead to soil compaction.

What is primary tillage? The first tillage operation of a season. The first tillage operation of a season. Works water and air in to the soil. Works water and air in to the soil.

What are the types of tillage equipment? Moldboard Plow Moldboard Plow  Inverts soil, turns residue under soil surface

What are the types of tillage equipment? Disk Disk  Rolling disks, similar to moldboard plow, better in sticky soils.

What are the types of tillage equipment? Chisel Plow Chisel Plow  Does not invert soil, uses chisels or sweeps that shatter the soil.  Leaves residue on surface.

What are the types of tillage equipment? Disk Harrow Disk Harrow  Similar to disk plow except smaller discs.  Cuts residue, but leaves on surface.

What are the types of tillage equipment? Rotary Hoe Rotary Hoe  Hoe wheels on long shaft dig into soil (shallow).  Usually mounted on tractor for row crops.

What is Hardpan? Compacted soil layer below the soil surface. Compacted soil layer below the soil surface. WHAT CREATES IT? Created by continuous tillage at the same depth. Created by continuous tillage at the same depth.

What is secondary tillage? All tillage operations after primary. All tillage operations after primary. Till at shallower depth. Till at shallower depth.

What is minimum tillage? Delay primary tillage until seeding. Delay primary tillage until seeding.

What are the benefits of minimum tillage? a) Soil surface is left covered residue (conserve moisture). b) Residue protects soil from erosion. c) Reduced costs (fewer operations). d) Soil tilth is improved (less compaction). e) Weeds are controlled with chemicals.

Six practices to minimize erosion No-Till No-Till Cover and green manure crops Cover and green manure crops Terraces Terraces Field windbreaks Field windbreaks Grass waterways Grass waterways Strip cropping Strip cropping

What is no-till? A planting method which the field is left almost undisturbed. A planting method which the field is left almost undisturbed. Plant materials are left on top of the soil, rather than tilled in. Plant materials are left on top of the soil, rather than tilled in. A narrow seedbed is prepared. A narrow seedbed is prepared.

What is no-till? (continued)

What is strip cropping? Alternating cropped fields with forage crops. Alternating cropped fields with forage crops.

What is contour tillage? Strip cropping so that fields are all at the same elevation (along hills.) Strip cropping so that fields are all at the same elevation (along hills.) Slows water runoff. Slows water runoff. Can reduce soil erosion by as much as 50%. Can reduce soil erosion by as much as 50%.

What is terracing? Earth structure built across the slope to hold water. Earth structure built across the slope to hold water.

What are windbreaks? A strip of trees or shrubs planted to reduce wind erosion and trap blowing snow. A strip of trees or shrubs planted to reduce wind erosion and trap blowing snow.

What are cover crops? Green plants plowed under for the purpose of building soil (AKA green manure). Green plants plowed under for the purpose of building soil (AKA green manure).

What are grass waterways? Strips of land permanently seeded to grass. Strips of land permanently seeded to grass. Controls water runoff from sloping land. Controls water runoff from sloping land. Best results when used with strip cropping. Best results when used with strip cropping.