Section 6: Soil Management for Erosion

What are the main forms of organic matter we apply

green manures

▪ straw

▪ manure

What level of organic matter improves structure

OM > 2% --- improvement in

structure

What level of OM requires large amounts of additions?

For soils <1% organic content, a

large supply of organic material is

required

Why do we till?

To control weeds, disease, and form a good seedbed

What is the main issue with tilling?

It destroys aggregate and has compaction risks

What are the 5 tillage types?

Conventional

No till

Strip till

Mulch till

Conservation till

Where do you use moldbor vs disk?

Moldbor is smooth, disk in stony soil

What do you need to do with all tilling types?

Plant on the contour to reduce erosion concerns

What practice helps in contour farming?

Planting strip cropping to help curb erosion losses.

How does tillage help erosion?

It does increase the roughness of a soil

What is conservation tillage?

Leaving at least 30% cover

Why is conservation tillage not allways used?

it requires specialized equpment and is ineffective in poorly drained soils

What is no till?

Tillage restricted to planting

seeds

▪ Drilling directly into the

stubble of the previous crop

▪ Weeds are controlled by

herbicides

WHat is strip tillage

Soil is prepared for planting along narrow strips, with

the intervening areas left undisturbed.

▪ Typically, up to one-third of the soil is tilled in a

single plow-plant operation

What is mulch tillage?

Similar to strip tillage, a seedbed is prepared in rows of mulch

What is minimum tillage?

15-25% cover with a focus on some cover.

What is sand slitting

Similar to a french drain, a narrow channel is cut into the land and filled with porous material like sand for drainage

Conditioners? Use?

organic by-products, polyvalent

salts and synthetic polymers.

Used in improvements to soil structure

Where are stabilizers used?

expensive for agricultural use!

can be justified on special sites like sand

dunes, road cuttings, embankments and

stream banks

What are the 2 types of soil conditioners?

render the soil hydrophobic & decrease

infiltration and increase runoff, and

▪ render soil hydrophilic, increase infiltration and

decrease runoff.

hydrophilic,

increase infiltration and

decrease runoff.

hydrophobic

decrease infiltration and increase runoff, and

What does tillage do to OM?

reduces it due to oxidation from sun

Isohumic factors? What do values indicate?

Speed of decomposition of products. Low values decompose fast but have low stability

What can be used instead of herbicide to control weeds in no till systems?

Large swaths of cover crops and a crimper.

What does contour length do with slope?

The interval decreases as slope increases

What is conditioners role in fertilizer?

Can be added to things like poultry litter to reduce runoff (gypsum)