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PNW Conservation
Tillage Handbook Series
Chapter 2 - Conservation Tillage Systems and Equipment, No. 22 (Updates
No. 19), May 1998
Direct
Seed Movement Gains Momentum
with 1998 NW Conference
Author: Roger
Veseth, WSU/UI Extension Conservation Tillage Specialist
There's been a phenomenal
increase in the use of direct seeding systems and more diverse crop rotations
across the Northwest, America and around the world. Nearly 900 Northwest
growers and Ag advisers attended the first Northwest Direct Seed Intensive
Cropping Conference on January 7-8, 1998 in Pasco, WA. The Conference
would have been even larger, but registration had to be restricted because
of space limitations. What is behind this huge interest in direct seeding
and alternative cropping systems?
Some important factors
driving these changes include: 1) increasing global market competition
and the need to reduce costs and improve profitability; 2) new crop rotation
flexibility under the 1996 Farm Program; 3) increasing grower and public
concern about cropland soil loss by water and wind erosion; 4) greater
awareness of the soil quality and productivity benefits of direct seeding
and detriments of intensive tillage; and 5) significant advances in management
and equipment technologies for direct seeding. The following provides
some examples and further explanation.
1) Competing
with the Competition -- This is the name of the game as NW growers
move into an increasingly global marketplace. Direct seeding and other
minimum tillage systems offer the potential to reduce production costs
and increase profitability.
Some examples of
1997 statistics may help provide some insight into how our national and
international competitors are moving towards direct seeding system. The
5% of PNW cropland was under no-till direct seed systems pales in comparison
to the U.S. average of 16%, Brazil - 15%, Canada - 18%, Argentina - 28%
and western Australia - 30%.
A brief review of
the rapid trend towards no-till in Argentina helps illustrate the tremendous
growth in no-till direct seed systems. In 1990, there was less than 2%
of Argentina's cropland in no-till. That grew to 6% in 1993, 19% in 1996,
and 28% in 1997, which is nearly 15 million acres. The 5% of Northwest
cropland under no-till in 1997 is about the same as Argentina's 6% in
1993. You could say that we are about four years behind Argentina in adopting
more efficient farming technologies. Western Australia is another striking
example, growing from 0.1% in 1989 to over 30%, about 10 million acres,
in 1997. There are similar trends around the world.
The potential advantage
of direct seeding on production efficiency was quite striking on a June
1997 Northwest grower tour in South Dakota. A direct seeding grower was
farming about 10,000 acres with two implements, a 100' sprayer and 60'
no-till air drill. Custom harvesters did the combining. It would be interesting
to compare the input costs of their two-pass operation with the same size
farm under conventional tillage, looking at the number of tractors and
implements needed, equipment maintenance, fuel, labor and other production
costs. If we are going to compete economically, we need to explore the
production efficiency potential of direct seeding and other minimum tillage
systems.
2) New Rotation
Flexibility -- The 1996 "Freedom to Farm Bill" finally
gave growers the cropping flexibility needed to develop crop rotations
critical to the success of direct seeding systems. For more than 50 years,
U.S. Farm Bills have been major obstacles to successful no-till and minimum
tillage systems in the Northwest and across the country. Commodity program
restrictions largely locked Northwest dryland growers into short crop
rotations in order to maintain their wheat base acreage, and high proven
yields for winter wheat. To manage weeds and diseases, they were forced
to rely on intensive tillage. Early NW attempts at no-till beginning in
the 1970's, in their traditional 2-year rotations with winter wheat, often
resulted in reduced yields or crop failures due to soilborne diseases
and winter annual grass weeds. At that time there was also little research
base or grower experience to guide growers in managing these new conservation
tillage systems.
3) Effective
Soil Erosion Control -- Water and air quality are becoming more
important issues, so the urgency for cropland erosion control will increase.
It is well documented by research and grower experience worldwide that
direct seeding systems can effectively reduce or totally eliminate water
and wind erosion. It is important, however, that all crops in the rotation
be managed under direct seeding or other minimum tillage systems to optimize
erosion control and soil productivity benefits.
4) New Insights
into Tillage Impacts and Direct Seeding Benefits -- The results
of recent research and long-term grower experiences in North America and
around the world are revolutionizing our understanding of the impacts
of tillage on soils. Contrary to the long-held belief that returning crop
residue to the soil with tillage builds soil organic matter, the real
impact of intensive tillage systems is a continual decline in soil organic
matter content. Organic matter is a critically important soil component
directly related to soil fertility, water holding capacity and infiltration,
aggregation and structure, erodibility, biological activity and a long
list of other soil properties affecting soil productivity and soil quality.
The increased oxygen
level and higher soil temperature present after tillage stimulate intense
microbial activity under moist soil conditions. A tremendous amounts of
carbon can be released as carbon dioxide during this accelerated microbial
decomposition of soil organic matter. The end result is that tillage is
biologically burning off soil organic matter faster than it can be built
with the addition of new crop residues.
Research shows that
no-till direct seeding systems result in very low carbon loss compared
to intensive tillage, consequently offering the greatest potential for
increasing soil organic matter content over time. The greater and more
frequent the soil disturbance, the greater the carbon loss potential.
With improved water conservation under direct seeding there is a corresponding
higher yield potential. For wheat, it is around 5 to 7 bushels/acre per
inch of additional water. The challenge for growers and Ag support personnel
is to develop the crop rotations and management systems to control of
pests previously controlled by intensive tillage in order to take advantage
of the higher yield potential.
5) New Direct
Seeding Technologies -- There have been some significant technology
advances since Northwest growers began trying no-till drills in the 1970's.
Many of the pest problems that occurred during the past 30 years can now
be largely avoided because of new research technologies. Here are a few
important examples.
Longer, more diverse
crop rotations have been shown to be very effective in controlling weeds,
diseases and insect pests that often occur in direct seed systems under
short crop rotations. Northwest growers, researcher, and industry representatives
are scrambling to find profitable alternate crops and crop rotations for
the different production areas of the region.
Another big technology
advance was identifying the impact and management of the "Green
Bridge," which has been a major cause of crop failures or sharply
reduced yields in direct seeded spring crops in the Northwest for over
25 years. Northwest research showed that the short time interval between
spraying a non-selective herbicide on volunteer and weeds before direct
seeding created a "green bridge" for root diseases and some
insects to attack the new crop. It can be effectively eliminated by spraying
as early as possible before seeding, beginning in the fall if possible,
and early spring at least three weeks before seeding. After this early
control, late spraying of very low populations of small, late-emerging
weeds and volunteer just before seeding will then have little "green
bridge" potential for root disease. Uniform distribution of chaff
from the combine is also an important starting point in managing the green
bridge and other concerns in direct seeding.
Research developments
on seeding equipment designs for fertilizer and seed placement have revolutionized
equipment for direct seeding. In the early 1970's, there were only about
5 models of "no-till" drills available in the Northwest, none
of which had deep fertilizer banding capability. Research has shown that
deep fertilizer placement below seed depth and near the seed row can significantly
improve yield potential under direct seeding, particularly with cereals
after cereals. Today there are over 40 drill models, nearly all with deep
fertilizer placement options. Improvements are still needed in hillside
performance and residue handling capabilities under some Northwest conditions,
but grower now have a large variety of equipment options. There are also
numerous examples of excellent grower and industry equipment modifications
to improve performance of direct seeding equipment in the region.
1998 Conference
Proceedings and Videotapes
The January 1998
Northwest Direct Seed Intensive Cropping Conference featured 48 speakers,
including 16 grower, from across the Northwest, Canada and Australia.
If you were unable to attend, you can have the next best thing to being
there!!!........Conference Proceedings and Videos. The detailed 150-page
Conference Proceedings of speaker presentation is available for $10 from:
NW Direct Seed Conference, P.O. 2002, Pasco, WA 99320, FAX 509-547-5563,
phone 547-5538. The Proceedings can also be accessed through the Internet
Home Page "PNW STEEP Conservation Tillage Systems Information Source"
(http://pnwsteep.wsu.edu). Videotapes
of the seven 2- to 3-hour Conference Focus Sessions are also available
for purchase ($15 each ) or loan. More than 100 sets of the tapes were
sold within three months after the conference. Call the WSU Crop and Soil
Sciences Dept. Extension office at 509-335-2915 (or FAX 335-1758) for
a complete video series description and order form.
The Pacific Northwest
Conservation Tillage Handbook is a large three-ring binder handbook
that is updated with new and revised Handbook Series publications. It
was initiated in 1989 as a PNW Extension publication in Idaho, Oregon
and Washington. Updates to the Handbook are provided when the updating
card is returned. By 1997, 34 new PNW Conservation Tillage Handbook Series
have been added to the original 98 publications Copies are available for
$20 through county extension offices in the Northwest or ordered directly
by calling state extension publication offices: Idaho -- (208)
885-7982; Oregon -- (541)-737-2513; Washington -- (509)
335-2999 (some shipping and handling charges and sales tax may apply).
It's now accessible on the Internet! All of the PNW Conservation Tillage
Handbook and Handbook Series are being put on the World
Wide Web Home Page (http://pnwsteep.wsu.edu)
titled Pacific Northwest STEEP III Conservation Farming Systems Information
Source. The Web site also contains recent issues of the PNW STEEP
III Extension Conservation Tillage Update, listings of other conservation
tillage information resources, coming events and much more. For more information
on the Handbook or updates to the Handbook, contact Roger Veseth, WSU/UI
Conservation Tillage Specialist, Plant Soil and Entomological Sciences
Department, University of Idaho, Moscow, ID 83844-2339, phone 208-885-6386,
FAX 208-885-7760, e-mail (rveseth@uidaho.edu).
Pacific Northwest
Conservation Tillage Handbook Series publications are jointly produced
by University of Idaho Cooperative Extension System, Oregon State University
Extension Service and Washington State University Cooperative Extension.
Similar crops, climate, and topography create a natural geographic unit
that crosses state lines in this region. Joint writing, editing, and production
prevent duplication of effort, broaden the availability of faculty, and
substantially reduce costs for the participating states.
For herbicide application
recommendations, refer to product labels and the Pacific Northwest
Weed Control Handbook, an annually revised extension publication
available from the extension offices of the University of Idaho, Oregon
State University and Washington State University. To simplify information,
chemical and equipment trade names have been used. Neither endorsement
of named products is intended, nor criticism implied of similar products
not mentioned.
Cooperative Extension
programs and policies comply with federal and state laws and regulations
on nondiscrimination regarding race, color, gender, national origin, religion,
age, disability, and sexual orientation. The University of Idaho Cooperative
Extension System, Oregon State University Extension Service and Washington
State University Cooperative Extension are Equal Opportunity Employers. |
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