Looking to add value to farmland? Drainage tile could be the answer. Excess water is often the limiting factor for an early spring plant, which dictates how long of a growing season a crop will receive. By adding drainage tile to a field that contains soils with water retention problems, the farm operator could plant the field earlier and grow healthier crops which would increase the land’s value. Drainage tile typically pays for itself through increased yields within five years of installation in farmland with drainage issues.

Sub surface drainage tile is a system of plastic tubing that is placed three to four feet deep under the surface of a farm field. The tile is perforated so it can absorb excess moisture from the soil around it. The excess water will travel through tile lines until it reaches an outlet, often a drainage ditch. Efficient tile should lower the water table within 24 hours of a rainfall, according to Iowa State University.

 

Tile pattern lines are electronically mapped out using GPS technology. The decision to tile a field heavily depends on the types of soils present. If certain portions of the field have efficient soils, then only low spots or poor soil quality areas require tiling. Fields can be tiled in a complete grid-style pattern, or strategically from a low spot to an outlet line.



The primary reason to install drainage tile in a farm field is to increase productivity through healthier crops. Ideal soil is made up of 50% soil, 25% water, and 25% air. When a heavy rain elevates the water table, the soil loses its 25% air make-up, which will hurt crop growth and increase soil pH levels.

Drainage tile will also allow for a field to dry faster in spring. Once the spring thaw occurs, farmers must wait until fields dry out before they can start to plant the current year’s crop. Heavy machinery cannot be driven on wet soil. Out of the 375 soils classified in Iowa, over half of them have excess water issues, according to Dan Hofstrand, co-director Ag Marketing Resource Center ISU Extension.

The earlier a farmer can get into a field and plant a crop, the longer the growing season of the crop will be. It’s not a coincidence that the more North you travel, the less yielding corn crops become. It is due to the decrease in growing degree days.

Tile is somewhat costly, but will provide additional income through increased cash rents because of higher production on the field. Tile will also immediately increase the farmland’s value and marketability. Farmers who own their own land typically see their tile projects paid off through increased yields within four to ten years.

If a portion of a field is always giving a farmer problem in spring and often doesn’t get planted due to excess water problems, that portion of the field could go from yielding zero bushels of soybeans a year to 55 bushels by simply installing drainage tile.



Environmental Reasons to Tile

Tile allows soil to work more efficiently at filtering excess water. Water runoff will carry fertilizer, chemicals and soil away from a farm field causing erosion and environmental problems in local water sources. An easy way to stop water runoff is by preventing it with tiling.

The limiting factor for growth in algae is phosphorus. Algae blooms often occur in summer when phosphorus leaks into a water source. Interestingly enough, phosphorus is immobile in soil, according to AgPhd. The only way phosphorus can leak into a water source, is if actual soil particles are carried into the water source, and that happens due to water runoff. Tile prevents phosphorus runoff, along with other chemical and fertilizers.

Not just any field can be tiled. The Natural Resources Conservation Service (NRCS) must OK if a field can be tiled. The NRCS promotes tiling, but not of any classified wetlands due to the conservation harm it could cause if water is lost. Tile can be laid through a wetland, but then the tubing cannot be perforated, rather it only acts as a transportation line for water from different areas of the field.

Increase in Value

The addition of drainage tile to the right soil types will increase annual income and value as a land owner. Since the operator will be able to produce higher yielding crops, they should afford to pay an increase in cash rents. Also, by increasing the farmability and quality of the field, the farmland’s value will increase as well. Even if it takes a while to pay for a tile project through increased rents, the project costs will be more than covered when the property is sold in the future.

- Colvin