A Brief History of Tillage

Jon Hanson, ARS

What is Tillage?

What is Tillage?

• Tillage is the mechanical manipulation of the soil and plant residue to prepare a seedbed where crop seeds are planted for production

• A tillage system is the sequence of operations that manipulates the soil to produce a crop:

– Chopping or shredding residue.

– Applying pesticides and fertilizers.

– Tilling.

– Planting.

– Employing post emerge weed control.

– Harvesting

Conservation Tillage

• To be considered conservation tillage, a system must produce, on or in the soil, conditions that resist the erosive effects of wind, rain, and flowing water. This resistance is achieved by the following activities:

– Protecting the soil surface with crop residue or growing plants.

– Increasing surface roughness.

– Increasing soil permeability.

– Using a combination of the three.

Types of Conservation Tillage

• Conservation tillage is concerned with maintaining an effective amount of residue on the soil surface.

• More recently termed Crop Residue Management (NRCS).

• Three common types of tillage systems:

– No-till (including strip-till)

– Ridge-till

– Mulch-till

The Beginning of Tillage

Bronze Age Crops

• Emmer (broadly, tetraploid wheat)

• Einkorn (the most primitive wheat)

• Barley

• Flax

• Chickpea

• Lentil

• Pea

• Bitter Vetch

The Advancement of Tillage

• Soil preparation has always been an important component of traditional agriculture

• About 10 millennia ago, Sumerian (ancient Babylon) and other civilizations developed simple tools to place and cover seed in the soil

• Farming from the Near East was introduced into Greece and southeast Europe more than 8000 years ago

Early Tools of Tillage

• A wide variety of early tillage tools included implements from the simple digging stick to a paddle-shaped spade that could be pulled by human or animals

• A wooden plow, called an “ard,” was probably developed in Mesopotamia about 4000 to 6000 BC

• The Triptolemos ard was named after the Greek God and hero about 4000 BC

Advent of the Soil-Inverting Plow

• The plow with iron share was widely used in Europe about 5th century AD

• The Roman plow evolved into a soil-inverting plow during 8th to 10th century AD

• The major advance before 1000 A.D. was the development of the heavy plough, which was more than the simple plows farmers used earlier

• It had a coulter designed to cut a thin strip in the turf and was a precursor to the moldboard plow

The Moldboard Plow

• In the 18th century, the moldboard, a curved board that turns over the slice of earth cut by the share, was introduced in England.

• Important improvements in design and materials were made in the early part of the 19th century

– streamlined moldboards,

– replaceable shares, and

– steel plows with self-scouring moldboards.

• Standardized the moldboard plow occurred by 1870

Expanded Use of the Plow

• With widespread use of the moldboard plow came the severe problems of soil and environmental degradation culminating into the Dust Bowl of 1930’s

A Change in Practice

• The use of the moldboard plow reduced sharply from about 46 million plows in 1977 to about 750,000 by 1988

• During this period, residue management and crop rotations became the dominate conservation methods employed for soil protection and increased production

• No-till agriculture also grew in popularity during this period

Introduction of No-Till

• The no-till movement began with the invention of 2,4-D after World War II

• In the early 1960s, no-till agriculture was not widely supported among farmers and agriculture specialists in the United States

• It was intended to be a way of farming without losing a great deal of soil, but few thought that no-till would make a difference in farming

• George Elvert McKibben, an Agronomist with the University of Illinois, made no-till the accepted farming technique that it is today

• Believing in his cause, McKibben said, "I was convinced from the start that it would succeed."

Principles of No-Till

The basic principles of zero tillage agriculture include:

– A system of crop production where the soil is not traditionally tilled

– Instead of tillage, the seed is planted directly into the soil

– Special planting equipment is usually required

– Most commonly the seeders require four-wheel tractors, although the seed can be dibbled in by hand (often using sticks to make the opening), or some small equipment suitable for animals or hand tractors can be used

– The system relies on retaining surface residue that reduces evaporation and limits weed growth

– The soil typically increases in bulk density, but porosity increases which improves water infiltration

Crop Residue Management

• The primary goal of no-till agriculture is the management of crop residue

• Most tillage practices remove large amounts of crop residue, for example

– the moldboard plow retains less than 10% of the residue,

– the chisel plow and disking retains between 25 and 75% of the residue,

• No-till agriculture on the other hand retains more than 90% of the crop residue.

• No-till farming is practiced globally on about 90 million hectares of the cropland

No-Till Expansion

Effects of Soil Surface Residue

Trends in Agriculture

• During the twentieth century, agriculture has undergone vast transformations in the United States.

• The number of farmers has decreased

• More farmers are relying on off-farm income

• Agriculture’s contribution to the U.S. GDP has declined

• A minority of non-metro counties in the U.S. are farming dependent

Trends in Agriculture

• However, each farmer is producing agricultural products for more people

Movement toward No-Till

All Crops—
Total Tillage

All Crops—Conservation Tillage

Small Grain—Conservation Tillage

All Crops—No-Till

Small Grain—No-Till

Current Trends in Agriculture

• Increased land degradation

• Competing land uses

• Focus on single ecosystem service

• Increase in farm size

• Movement toward commercialization

• Genetic engineering

• Global markets

• Changing social structure

Conclusions

• The face of agriculture continues to change

• Agriculture is increasingly blending production and environmental practices

• The needs for tomorrow include new agricultural management systems that are designed to provide alternatives that are environmentally and economically compatible and sustainable while maintaining a high degree of social acceptability

• No-tillage will play a key role in emerging national and international issues

Future Challenges

• The agricultural community will face many new and difficult challenges in the years to come

• New agricultural management systems need to be developed that include consideration and inclusion of economics and economic policies, environmental sustainability, social and political concerns, and new and emerging technology

• These systems can ultimately assist land managers to develop new and improved sustainable land-use strategies to the benefit of generations to come