The spring 2019 weather oscillated between periods of rain and cold, which delayed planting and left some farmers with little choice but to seize any opportunity to get in the fields. However, in those conditions, farm machinery’s footprint poses a huge risk of soil compaction, and the consequences have long-term effects on the health of the soil and on plant development.
Phillips, an agronomist and Channel seed salesman, says his goal is to make his clients better, whether by giving hybrid seed recommendations or investigating issues with a crop to give a second opinion on management decisions. In wet, cool years like 2019, compacted soils increased the risk of root disease and overall stress to the crop, so mitigating soil compaction was one of the highest priorities he pushed throughout the season.
“Soil compaction is one of the biggest issues in agriculture, and there’s no right answer on how to manage it,” Phillips says. “Not a lot of people realize that yield loss from compaction doesn’t just happen in spring. You have to spend all year managing it. But if you put in the work up front, you can minimize compaction’s effects on yield.”
COMPACTED SOIL STRUCTURE
When soil suffers compaction, myriad challenges arise.
Compaction causes soil particles to squeeze together, reducing pore spaces that hold CO2 and oxygen. With fewer pores, water infiltration and drainage are reduced. When it rains, the water sits on the soil, putting it at risk of causing erosion and sediment loss.
Tightly compacted soil is tough for plant roots to penetrate; you’ll find poor seedling emergence due to stunted root growth, exhibiting as narrowed tomahawk or flat pancake roots. “Since 90% of a plant’s nutrition is taken up 6 inches below the seed, it must be able to access the nutrients to develop properly,” Phillips says.
In addition, compaction can adversely affect yield, depending on the degree of severity. The results of a study by University of Minnesota Extension Educator Jodi DeJong-Hughes and Frenchie Bellicot, a consultant, indicate a 17% yield decrease across seven research sites that were chisel-plowed, disk-ripped, and spring field-cultivated.
On the surface, appearances can be deceiving on the extent of the damage. It’s also difficult to calculate how long it will take to correct. Phillips says, “Compaction isn’t easily repaired. Beyond the short-term effects of compaction on the growth and development of a crop, if it isn’t managed properly, it will take years to rebuild soil structure.”
Awareness of the soil conditions and your management practices can help you develop strategies to reduce soil compaction risk year-round.
THE REYNOLDS FARM
When northwest Iowa seemed to be littered with saturated fields last spring, Dan Reynolds, a third generation farmer and his two sons, Clay and Adam, leaned on Phillips to ensure the quality of their crop and resilience of their soil.
“We rely on Andrew to make decisions for us on compacted ground,” says Dan Reynolds. “I’ve farmed for 40 seasons, but I don’t know everything. He works with us to scout the fields, check on issues for us, and help with hybrid selection.”
The brothers, fourth generation on their land, returned home after college to farm the corn and soybean operation and raise cattle and goats. Clay and Adam draw on their technology experience and ag business backgrounds to introduce new management practices. While Dan says they’re always in “go mode,” it’s been rewarding to see his sons make day-to-day decisions that have made their farm better.
The Reynolds’ recent challenges with compaction began in the fall of 2018, when rain and cold temperatures delayed harvest and fall tillage. This led them to anticipate a tough planting season with the potential for even more compaction ahead.
“We ripped up some of the wet, tacky fields to break up compaction and depended on Mother Nature’s freeze-thaw cycle to do some work, too,” Clay recalls. “The winter was so cold, though, we found broken tiles in the spring and had more to fix.”
With a name like “No Plant ’19,” the Reynoldses had to be strategic in order to successfully get their crop in on time and to minimize compaction on fields already struggling to recover from a rough fall and winter. Their game plan focused on implements, technology, seed selection, and scouting.
“We changed to tracks on our tractors, which are wide, and that lowers the PSI on the soil. Our planter can cause the most compaction in the spring, but by not filling the planter boxes full, we eliminate approximately 3,000 pounds of compaction. If we go into an 80-acre field, we only put 80 acres worth of product in,” says Dan.
In addition to these changes, Phillips recommends using good closing wheels and downforce on your planter and planting the most stress-tolerant crop or hybrid. He says a hybrid alone won’t fix compaction but will help you avoid some stress on the plant.
The Reynoldses’ planting plan is a moving target that adjusts per the weather. They make as few trips across fields as possible and do as much minimal-tillage as they can, yet they evaluate each field individually. They evaluate the soil profile, if a field is tilled or no-tilled, if it’s a ripped field vs. a disk field, and alter their approach.
According to Phillips, the best thing to do is not go into fields when it’s too wet. Utilizing tools (like Climate FieldView) that track rainfall amounts by field can help.
“If you have few opportunities to get out when it’s raining, you might have to ask yourself which field would be the best one to start with and go from there. It would surprise you how fields only miles apart can have drastically different rainfall amounts,” Phillips explains.
PLANTING PLAN AND EARLY SEASON RESULTS
Patience and planting soybeans first became two integral steps to the Reynoldses’ planting plan.
“It’s hard to wait, but we held off on planting our corn because if we were to mud it in, our top-end yield potential would be gone for the year. We only have one shot to get it right,” says Clay.
Phillips explains, “When conditions aren’t perfect for corn, you can plant soybeans, because the taproot can handle more stress. Also, if emergence on soybeans is not perfect, they will compensate by branching out and filling the gaps to minimize yield loss.”
Their patience paid off. They were able to plant their corn and finally saw it take off with a good emergence and stand once the heat of the summer kicked in. The early- planted soybeans also showed promising yield potential.
Even so, they faced some compaction challenges with known trouble spots in their fields.
“When we were done spraying the corn, we had time to replant where there was standing water in the bean fields,” Clay says. “We tried to give those areas a second chance, but during the last week in June, we got heavy rains again that killed off the beans. Sometimes it pays off, sometimes it doesn’t. Mother Nature won the battle that year.”
SECURING PLANT HEALTH
While you may be implementing specific practices to correct or avoid soil compaction, it’s also important to ensure your plants stay healthy throughout the entire growing season.
Phillips likens plant health to human health. You may battle a cold for several days, but if you are otherwise healthy and don’t face long-term health concerns, you are more capable of healing quickly and getting back to work.
“It’s not always about disease; it’s about general plant health and understanding how to get the best consistency throughout the field. You get yield by making the plants feel the best they can every day,” Phillips says. Diagnosing problems early ensures you can address the issues before it’s too late.
The Reynoldses, along with Phillips, invest a lot of time scouting their soybean fields for disease and pests and discussing which applications they should make. They navigate their cornfields checking stalk quality, looking for insect damage, and gauging the quality of the crop for harvest.
Late in the season, the weather once again turned cool and rainy. Even though the Reynoldses had few problems and little compaction to contend with, they set a plan in motion to avoid major pitfalls of compaction and to get fall fieldwork done on time, both challenges they saw in 2018.
“The biggest issue we faced in the fall was the limited opportunity to get out into the fields,” Phillips says.
He and the Reynoldses checked ground moisture early for risks like corn standability issues from crown rot, a concern because they planted in wet and cold weather in the spring; late disease pressure because fungicide was applied earlier in the growth cycle; and corn sprouting and molding in the husk because of late rains, which were unusual for the season.
Phillips anticipated heavy compaction in the fall and recommended cover crops, tillage, and changing fertilizer application in order to not make matters worse.
Every year at harvest, the Reynoldses establish limited traffic patterns for the semis, keep tracks on the tractor, plant cover crops, do a combination of no-till and tillage practices, and rely on a freeze-thaw cycle to break up crusted areas of the field.
In spite of the volatile weather, challenges with replanting, and extended cold during harvest, the Reynolds’ corn yield averaged 12 bushels more per acre than 2018 and their early planted soybeans averaged six bushels more per acre than their late-planted crop.
Soil compaction’s consequences are many and long lasting, so taking steps throughout the year to eliminate as much damage as possible will pay dividends.
Just like the Reynoldses and Phillips did in 2019, exercise patience for the right field conditions, adjust equipment, designate travel zones, plant cover crops, and build relationships with like-minded partners.
No matter how 2020 shapes up or what the calendar says, employ these strategies to ensure healthy soil, crop, and yield, so you can get fieldwork done with time to drive around peacefully admiring the land.
RECOMMENDATIONS AS SPRING PLANTING APPROACHES
Dan Reynolds: “You have to be open to change. The weather will always throw you curveballs, so you have to consider all of the options.”
Clay Reynolds: “When Mother Nature is shining, you should be driving around to your fields, checking crops every day no matter if it rained the day before and all seems well. Crop conditions can change quickly.”
Andrew Phillips: “There are a lot of tools and products you can use to create a plan (and backup plan) that fits into your specific operation, like tillage, tile drainage, hybrid varieties, grain bin storage, etc. Keep an open mind and use what Mother Nature gives you so you can be proactive today and all season long.”
This article originally ran on Successful Farming on March 10, 2020. You can find the full article at Agriculture.com.