Now is a good time to evaluate and perform maintenance on terraces in wheat stubble or fallow ground, saids Greg Bauer Barton County Supervisory District Conservationist
In Kansas, over 9 million acres of land is protected by more than 290,000 miles of terraces, making Kansas No. 2 in the U.S. for this soil and water conservation practice. To accomplish their purpose of erosion control and save water, terraces must have adequate capacity, ridge height and channel width.
“Without adequate capacity to carry water, terraces will be overtopped by runoff in a heavy storm. Overtopping causes erosion of the terrace ridge, terrace back slope, and lower terraces -- and may result in severe gullies.
Terraces need regular maintenance to function for a long life. Erosion by water, wind, and tillage wears the ridge down and deposits sediment in the channel, decreasing the effective ridge height and channel capacity.
“Terrace maintenance restores capacity by removing sediment from the channel and rebuilding ridge height.
Terraces degrade naturally by erosion and sediment, and can be damaged by machinery, animals, settling, and erosion.
“Check terraces and terrace outlets regularly for needed repairs. The best time to check is after rains, when erosion, sedimentation, and unevenness in elevation are easiest to spot. Specific items to note are overtopping, low or narrow terrace ridges, water ponding in the channel, terrace outlets, erosion, and sediment clogging near waterway or pipe outlets.
Terrace maintenance can be done with virtually any equipment that efficiently moves soil. Common tools include:
* Moldboard plow, disk plow, one-way, 3-point ridging disk and belt terracer
If silt bars and sediment deposits are accumulating frequently in a terrace channel, and excessive erosion is the cause, a change in tillage and cropping practices is needed to correct this problem.
“In this situation, conservation tillage and crop rotations that retain crop residue will reduce erosion substantially. This will reduce the frequency of terrace maintenance needed. Many no-till producers find terrace systems require little maintenance. Although runoff still occurs, there is very little soil movement in a no-till system.