Tuesday, November 6, 2007 - 10:00 AM
202-3

Developing and Testing a Trafficability Index for the Texas Blackland Prairie.

Adam Helms, Soil & Crop Science, Texas A&M University, 370 Olsen Blvd, College Station, TX 77843-2474, Cristine Morgan, Department of Soil & Crop Sciences, Texas A&M University, College Station, TX 77845-2474, Gaylon Morgan, Rm 349B Heep Center, Texas A&M University - Soil and Crop Sciences, Texas A&M University, Soil & Crop Science Department, College Station, TX 77843-2474, and Kenneth Potter, USDA-ARS, 808 E Blackland Rd, Temple, TX 76502.

The Texas Blackland Prairie is one of the most productive soils yet difficult to manage properly because of its high clay percentage. Therefore, a decision support tool to aid farmers for trafficking events on their land might be beneficial for producers. This study is developing and testing a trafficking index for planting and tillage events on the Texas Blackland Prairie. The index can be incorporated into a decision support model for precision management. The Blackland Trafficability Index was developed by creating five moisture regimes and ranking them from 1 to 5; Too Dry (1), Dry Workable (2), Optimal (3), Wet Workable(4) and Too Wet(5). Experienced producers on the Texas Blackland Prairie were used to create the index in no-, strip, and conventional tillage. Preliminary Blackland Trafficability Index results indicate a narrow workable trafficability from 18 to 28%, based on volumetric water content. The three middle indexes were chosen for field evaluation; they were 0.18, 0.24, and 0.28 cm3 cm-3 for index numbers 2, 3, and 4 respectively. Corn and cotton were planted into no-tillage and conventional tillage fields at the three middle moisture indexes. After planting 0.45 x 0.30 x 0.15-m soil blocks were collected and placed into a growth chamber. After four weeks, seed furrow smearing, stand establishment, root growth and water stable aggregation were quantified. Results from the first year of data will be presented.