By RENEE JEAN, Williston Herald
Drive past an area where a pipeline has been put into a farmer's field, and it is quite likely even your untrained eye can spot the difference in the terrain. Sometimes that difference is still stark, even 20 years or more later.
North Dakota remains a land of agriculture spreading out far and wide. But as the oil game matures, more and more pipelines are being laid ahead. Figuring out what methods will work best to reclaim that lost land once a line is laid is becoming more and more of a crucial quest.
Over the years, a number of groups have looked at the problem from various vantage points. Individual farmers have tried different things with varying degrees of success. Meanwhile, the pipeline industry itself has looked for the most economical approaches and often has its own environmental teams devoted to the task.
More recently, the Williston Research Extension Center was gifted with an opportunity to study pipeline reclamation up close and personal. A roadway and then a pipeline were laid on the outer perimeter of the research farm near Williston.
Among the researchers working to reclaim that land is Austin Link, with WREC. He is working on a multi-year study that will examine the effect of different cropping rotations with annual and perennial cover crops and manure applications to rehabilitate the health of that disturbed soil.
Several rotations will be tried, including wheat on wheat and perennial alfalfa, Link told the Williston Herald. The rotations were selected based on studies performed by Don Tanaka, who has been looking at reclamation of intensely farmed fields.
The question there, Tanaka says, is whether the fields can be restored to the state they were in when they were broken out of the native range, and what's the best way to do so, from an economic standpoint.
Farmers know that the original native range is really good farmland, Tanaka adds, because when they've inadvertently tilled up a new corner in a pasture, the wheat in that little tip always does so much better.
"It's also a question a lot of people are asking, mainly because of the high price of fertilizers and other inputs," he said. "We have to put in crops with cheap crop prices, and the high price of fertilizer is making it tough to make ends meet."
Tanaka has so far identified five principles to rebuilding soil health and vitality, and these are helping to inform the choices in Link's pipeline reclamation study.
Tanaka's principles include avoiding tillage as much as possible and using cover crops to help feed the soil. Maintaining crop residue helps prevent erosion and holds in moisture, while a rotation of crops gives the microorganisms something different to eat, helping build soil diversity. He found a rotation like winter wheat, peas, corn, safflower created a better dynamic for both soil health and economic return. Safflower follows corn in the rotation because, even though both are deep-rooted crops, he found yields were better than usual that way.
Meanwhile, spring wheat after corn is not recommended. It risks scab and other diseases, which puts a damper on yields and thus isn't the most economical choice for growers.
It's the first year of the WREC pipeline reclamation study, so not a lot of data has been collected yet for producers to apply in their own fields. At the farm, white signs mark the roadway, and then the pipeline study lies just beyond that. These areas were pointed out during the MonDak Ag Showcase in July.
"Some barriers we ran into were, we had severe compaction and crusting over the pipeline and the pipeline area," Link said.
The compaction was so bad in places, drilling seed into the ground was itself problematic.
"In the alfalfa treatment, we used a True-ax drill which the NCRS is using for reclamation seeding, and it wouldn't penetrate the soil," Link said. "We used a John Deere 750 drill, and that did better."
Tests have been run at this point for compaction and infiltration, though not for pH, because there wasn't even any topsoil until May.
"Compaction was evident," Link said, "and what you'd think you'd find for a pipeline. The top was very firm, but there were also really light areas, just pointing to the fact it's probably going to settle."
Some areas had such severe compaction, the meter wouldn't go farther than 3 inches down.
"We were trying to get to 18 inches for the trial," Link said.
All of which means, reseeding in the fall is likely, along with some light tillage to prepare the seedbed.
At this point, the reclamation study is going to rely on deep-rooted plants to address compaction. Researchers said they have not ruled out some deep ripping in certain areas, particularly on the road bed area where compaction was highest, but are viewing it as a last resort. Ripping brings up a lot of rock, so it's something they hope to avoid.
Meanwhile, there are other problems that can come into play with the pipeline reclamation. Salts can be brought to the surface, as well as clay, both of which are difficult to work with.
While not much data has yet been collected, there are any number of ways such studies can go in the future, Link said.
Link will run the various cropping systems for four to five years, after which the entire study area will be put into the same wheat variety. A yield study will be done to see which system has produced the best soil for farmers.