Impact Of Wheel Tracks On Surface Drainage & Yield

Introduction

This case study examines the impact that tractor wheel tracks can have on surface drainage and then yield. The case study is from a farm in USA that grows vegetables. The field has some depression area that hold water after rainfall events but this problem is exacerbated by the small furrows create by the ‘controlled traffic’.  This is the clearest case we have seen showing the directions and depths of wheel tracks affecting drainage and then yield.  We have also seen this problem in grain crops around the world.

All tractor traffic is controlled by RTK GPS which forces the tractors to traffic over the same area each time also known as ‘controlled traffic’. Although ‘beds’ are not specifically created to grow the crop on, the continual traffic in each path compacts the traffic ‘lane’ so that  a small furrows is formed.  Soil is also pushed sideways away from the traffic lane to increase the effective depth for the furrow. The furrow created can be up to 4 inches deep (100mm).

Runoff from rainfall and irrigation concentrate in the wheel tracks and flow along the furrows towards a low point. If the wheel tracks were not there, then the water may have an opportunity to move sideways perpendicular to the furrows. But the water that stays in the wheel tracks waterlogs the crop and reduces yield.

See the video below to better understand the problem. Note how the water is standing in the furrows and the crop is decimated.

Existing Topography

Here is a map of the existing topography. Contour lines are 0.3ft apart. There is significant slope on this field.

There are only a few depression areas that would hold water if no wheel ‘furrows’ were present a show in the next map drainage.

Drainage Analysis

Drainage Analysis With Furrows Rotated 90 Degrees