Tillage

Chapter #10

What is Tillage?

the practice of keeping the soil mellow (soft) and free from weeds mechanically (physically)

can be seedbed preparation or postemergence cultivation

What are the purposes of tillage?

1) develop soil tilth (physical condition of the soil)

2) kill weeds 3) manage crop residue

What is a seedbed? place where seeds germinate & nourish

young plants must be firm to allow seed to come in

contact with soil particles to absorb moisture

must be pourous to allow air to move, root development, water movement

water will not easily penetrate hard soil to get to roots

Seedbed Characteristics if soil is too loose, rain will wash away

young plants some soils have excess water oxygen is needed by roots air and water conduct heat more rapidly

than soil, looser soils warm up sooner plant residue on surface insulates,

warms up slower, also provides buffer against wind

What is Soil Tilth?

The physical condition of the soil fitness for cultivation

How is good soil tilth developed?

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 blow

over tillage will destroy soil structure and lead to soil compaction

What is the definition of a weed?

a plant that grows out of place -tillage can cut roots or bury weeds

Is crop residue a benefit or detriment?

definitely a benefit helps control erosion, retain water,

improve tilth

What is primary tillage?

the first tillage operation of a season loosen soil to permit air and water to

penetrate dark soils absorb light, warm up quicker residue insulates, warms slower in wet areas soil is plowed in dry areas leave residue

What are the types of tillage equipment?

• Moldboard Plow: inverts soil, turns residue under soil surface

Disk Plow

rolling disks, similar to moldboard plow, better in sticky soils

One-Way Disk Plow

for dry soils, leaves more residue on soil surface than moldboard and disk plow

What is summerfallow?

tilling uncropped land in summer primary tillage is deepest, rest shallower leave residue

Chisel Plow

does not invert soil, uses chisels or sweeps that shatter the soil

leaves residue on surface

What is Hardpan?

compacted soil layer below the soil surface

created by continuous tillage at the same depth

How can hardpan be corrected?

use a subsoiler

Disk Harrow

similar to disk plow except smaller discs, tandem. cuts residue, but leaves on surface

What is secondary tillage?

all tillage operations after primary till at shallower depth

Spike-Tooth Harrow

steel spikes that break soil crust, uproot small weeds

Rod Weeder

rod turns as it is pulled beneath the soil rod turns opposite direction as wheels,

lifts weeds and coarse material to surface

packs seedbed

Rotary Hoe

hoe wheels on long shaft dig into soil (shallow)

usually mounted on tractor for row crops

What is minimum tillage?

delay primary tillage until seeding

What are the benefits of minimum tillage?

1) soil surface is left covered residue (conserve moisture)

2) redidue protects soil from erosion

3) reduced costs (fewer operations)

4) soil tilth improved (less compaction) -Weeds are controlled with chemicals

What is stripcropping?

alternating summerfallow and cropped fields

What is contour tillage?

strip cropping so that fields are all at the same elevation (along hills)

slows water runoff

What is Terracing?

earth structure built across the slope to hold water