Sparks opened his lab in Lincoln in 1974, offering agricultural
soil testing for area farmers and fertilizer dealerships.
By 1996, GPS was beginning to play into soil testing, and the
use of computers was becoming more important in the profession.
Phillips said these were aspects of technology that his
stepdad wasn't comfortable with, so Greg came back to help
integrate new technology into the lab. Now, all these years
later, he's still here, having taken over in 2004 as the owner
of the family business.
Using GPS in soil testing has fine-tuned the way soil samples
are taken and how they are documented for the farmers, but
beyond that, the testing business is something that really
hasn't changed a great deal over the years.
What was proven decades ago still holds true today: Soil
needs proper pH balances, phosphorus and potash in order to grow
good crops, along with nitrogen for corn.
Soil testing helps farmers see what their soils are lacking
and helps them determine how much fertilizer or chemicals that
modify acidity need to be applied to a given field in order to
produce a high-yielding crop.
It takes 0.43 pound of phosphate and 0.28 pound of potash to
produce one bushel of corn. Knowing this, farmers can examine
what is already in the soil at the end of the season and then
calculate what is needed for the next growing year.
For soybeans, the nutrient requirement is 0.85 pound of
phosphate and 1.3 pound of potash per bushel produced.
GPS can also play into saving dollars for the producer. Using
satellite imagery, Phillips creates a map of the field and then
marks where the soil samples were taken. When test results come
back, he sees where soil nutrients are richer or weaker and
adjusts fertilizer applications accordingly.
According to studies by the University of Illinois Agronomy
Department, GPS mapping can save producers as much as $3 to $5
an acre on fertilizer applications.
Several years ago there was a push in soil testing to include
analysis for micronutrients such as boron, chloride, copper,
iron, manganese, molybdenum and zinc. Some of the larger, more
commercial labs have incorporated those tests into their
standard analysis, but Phillips said that on the whole, it
really hasn't panned out.
In most cases micronutrient deficiencies will show up on
plant foliage and can be identified visually. Phillips said that
from there, the best practice would be to do a plant tissue
Oddly, Phillips said, scientists are seeing a depletion of
sulfur in soils. This comes from the fact that environmental
standards regulate the amount of sulfur emissions from
coal-powered plants. Phillips said that certainly isn't a bad
thing, as we don't need the sulfur in the air, and it is better
for all of us to add sulfur to the soil when needed than to see
it coming "naturally" from acid rain.
Sulfur is needed by plants in about the same quantities as
phosphorus and, depending on the crop, removes between 10 and 80
pounds with each harvest.
In spite of the known crop needs for sulfur in relatively
large amounts, scientists have struggled to get a good handle on
this nutrient. Soil and plant analysis procedures are not yet
refined to the point where standard recommendations can be made
Looking to the future, Phillips said that what the industry
needs and is working toward is a reliable method for testing
nitrogen in soils.
"We're just waiting for a breakthrough from the ag
universities. They have been working on trying to do tests on
nitrogen, but nitrogen moves up and down in the soil, and with
our current technology it is an impossible test."
So what lies ahead?
Phillips said that Logan County farmers can look forward to
working with some of the richest soils in the state for
generations to come.
"Logan County soils are some of the best in the state," he
said. "Based on the last glacial period, they're very young
soils. Maybe a thousand years from now, farmers may have to go
to a four-crop rotation like the British did to replenish the
soil, but these are very rich soils and they are going to
continue to be for a long time."
[By NILA SMITH]
Excerpted from the LDN
2011 Farm Outlook magazine