One reason fertility recommendations have earned a bad reputation is they often involve more philosophy than science, says Greg Patterson, president of A&L Soils Canada.
“A farmer will take a fertilizer recommendation from his favourite soil lab and shop it around. He’ll take it down to a fertilizer dealer and then maybe over to an extension office,” Patterson said.
“So now he has three different opinions, three different fertilizer recommendations all based on the same soil sample. Next, he adds them all together and divides by three and that gives him a fertilizer rate he thinks is correct. Well, nothing could be further from the truth. This is not science.”
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Patterson said it’s nothing more than the average of three opinions, based on three peoples’ differing philosophies about fertilizer. It ignores the science of the soil analysis.
“Lock three agronomists in a room with the same soil report and you’ll get six different fertilizer recommendations, probably all partially correct,” he said.
“The interpretation of the raw data is all a matter of the philosophy of each individual.
“Our philosophy is different. We don’t think a soil lab should tell a grower how much fertilizer to apply. We think a soil lab should put as much scientific information as possible on the soil report so farmers and consultants can apply their own knowledge of the farm, the field history, the rotation, the markets and other factors. They can then make their own logical decisions. That’s better than me trying to do a fertility recommendation from my desk.”
Patterson said that although A&L does provide fertility recommendations, it’s a secondary part of the company’s service. He said its main emphasis is to teach people how to read a soil analysis and interpret the data for themselves.
A&L conducts training seminars during the winter, giving consultants and producers an in-depth look at what the soil report means and how the data can be used to create better profit margins.
The seminars are short courses in soil science, tailored to the soil and crops of the area. Patterson said they cover soil chemistry and plant physiology, with the goal of teaching people what the numbers mean in their specific situations.
“There’s a reason the recommendation game has been getting so beat up over the years,” he said.
“You’ll often hear a farmer or an extension person blasting one soil lab or praising another. It’s because of too much emphasis on the fertilizer numbers and not enough emphasis on the scientific process of arriving at those numbers. The process is the most important thing. The recommendation comes second.”
This doesn’t mean Patterson thinks A&L has all the answers.
“If you look across North America, you’ll see that the different provinces and states all have different ways of calculating nitrogen recommendations,” he said.
“That pretty well tells me that nobody really knows N. And we don’t know enough about it either. Nobody knows for sure.”
Patterson said the best farmers can do is immerse themselves in the soil analysis process. The more a producer can distance himself from the routine acceptance of fertilizer recommendations, the closer he is to better profits.
“We encourage farmers to write their own fertilizer recommendations. Soil labs should not write them for you,” Patterson said.
“Take a sample from your best spot in a field and another sample from the worst spot in that field. Do the two separate analyses and see what kind of numbers you get. The numbers will give you a pretty good idea of why you’re doing what you’re doing.”
Patterson said some of the information on an A&L soil report will be similar to what comes out of other labs, based on research conducted in the last half century.
But there is an important difference, Patterson said. A&L has invested in research and has developed its own proprietary soils data in recent years.
“Because we’re farmer-owned, we have made a deliberate decision to conduct our own in-field research to address soil and fertility issues pertinent to the soils we farm.”
A&L was formed 20 years ago when Ontario potato growers wanted access to better soil and fertility research to meet their needs. They bought an existing soil lab and operated it to suit their own purposes.
Although it is still an affiliate of A&L International, with offices around the world, the company remains an independent soil lab, owned and operated by the founding farmers.
Through the 1990s, as the company continued to address the requirements of its owners, it also began serving other farmers coast to coast, including the three prairie provinces, which meant expanding its research to encompass the new landscapes.
“Today, we get involved with all kinds of growers groups and researchers, working on plant health, plant nutrition and how to correct problems by addressing soil issues,” he said.
“We have data on everything from apples to zucchini, and that includes canola and wheat, of course.”
Although A&L’s lab is in London, Ont., the company does a lot of business in Western Canada. Because of increased demand from the Prairies, it has established agents in Manitoba, Saskatchewan and Alberta through an independent agency called Taurus Technology Group.
Regardless of which region of Canada is involved, a main focus of A&L research is how farmers use nitrogen. Patterson said excess nitrogen wastes money and contributes to a variety of growing and quality problems. In virtually any cropping situation, better nitrogen management leads to better quality crops and profit margins.
“In agriculture, we have this love affair with nitrogen,” he said. “It’s one of those instant gratification things. You put it on and the crop picks it up and grows and looks good.
“Other nutrients like phosphorus and potassium give us only 15 to 20 percent response in the year of application. It’s not visually gratifying. But nitrogen can give us up to 75 percent response in the year of application. It’s a very quick and very visual response, so we overapply it.
“And now, on top of all that, we’re faced with the whole environmental issue of ground water nitrates. The grower today has little choice but to become better educated and better informed in managing nitrogen inputs.”
Patterson said the lab uses soil nitrate numbers and plant tissue numbers in conjunction with nitrogen release values that the company has developed through its own research.
He said optimal nitrogen use depends on understanding the relationship between organic nitrogen in the soil and how it will release to the crop through the growing season. The various soil nitrate tests and plant tissue tests A&L conducts relate to those secrets of organic nitrogen.
“We gear all of our work to realistic yield goals for each specific soil. We put enough information on a soil report so a farmer or a consultant can make their own logical decision to maximize the efficiency of the form of nitrogen to be used in that year.”
He said that realistic is a key word in A&L’s vocabulary. Each soil has an inherent maximum level of productivity, beyond which input dollars are wasted. Everything A&L recommends must be practical and economically viable, he added.
A unique aspect of the program is its two-part soil report. One part deals exclusively with meeting the nutrient requirements of the crop in the upcoming growing season. It does not address the long-term needs of the field.
The second part concentrates on building up all nutrient levels in the soil to a point where the field is capable of achieving optimal yields over the long term.
How quickly a producer implements his soil building plan depends on how much money needs to be invested and how much cash flow can be diverted into the building process. Some growers set a time line of three years, while others stretch it over 10 years.
“Everyone in the industry pretty well agrees on how much phosphorous and potassium a crop takes out of the soil, but there’s a lot of disagreement on the optimum level of phosphorus and potassium in a particular soil.”
Patterson said the understanding of phosphorus and potassium was primitive before 1974, when scientists first began to differentiate between clay soil and sandy soil and to look at optimum levels for these two nutrients in different soils.
A&L uses the standard cation exchange capacity method, or CEC, to assess a soil’s ability to hold positively charged nutrients such as potassium, magnesium and calcium. CEC numbers relate to the amounts and types of clay minerals and organic matter and is expressed as milliequivalents per 100 grams (meq/100 g) of soil.
The rating will vary from two to 35 meq/100 g depending upon the soil type. Soil with high CEC will generally have higher levels of clay and organic matter.
For example, a silty clay loam texture would have a considerably higher CEC than a sandy loam soil. Although high CEC soil can hold more nutrients, good soil management is required if these soils are to be more productive.
“Based on this rough reference of the type of soil, and also on our own original research, we can now come up with optimum levels of phosphorus, potassium, calcium and magnesium for that soil sample,” he said.
“Another thing we do differently is to take our own precision ag research and apply it to the potash-magnesium relationship we see in the chemical analysis. We interpret that relationship and give it a numerical value on the report so the producer starts to gain an understanding of the true potential of each zone.
“That’s just the start of the soil building process. Now we get to the soil building part of the soil report. With these numerical values, we can come up with recommendations to build the nutrients up to optimal levels. We usually suggest a gradual building process of three to five years in most cases.”
Most of these soil building plans are aimed at bringing medium quality soil up to a level Patterson terms as good.
Other plans might deal with giant steps for building poor soil or small steps for maintenance plans in soil already near an optimal level. There might be a number of different plans for different areas of a field.
“If you have eight zones in a field, then we look at each one individually,” he said.
“Each zone will have it’s own optimal level. You’ll get two recommendations. One for a long-term build plan for each zone and another for crop performance in the upcoming growing season for each zone.”
Like most quality soil labs, A&L is accredited by the North American Proficiency Testing Program and the Canadian Association for Environmental Analytical Laboratories.
“We all go through the same periodic quality testing so we all know that our numbers are accurate. That’s a given,” Patterson said.
“As for ISO criteria, we are one of only two labs in Canada with the ISO 7025 certification for soil analysis.”
Patterson said the company’s price list is similar to that of other soil labs serving the Prairies.
The basic analysis for 16 factors is $27. The complete analysis for 21 factors is $41.60.
For more information, contact Greg Patterson at 519-457-2575 or visit www.alcanada.com.
