Deep Soil Profile Sampling of Nitrate for Residual Nitrogen Credit in Winter Wheat - Texas Blacklands

Project Overview

Project Type: On-Farm Research
Funds awarded in 2016: $15,000.00
Projected End Date: 03/14/2018
Region: Southern
State: Texas
Principal Investigator:
Dr. Jake Mowrer
Texas A&M Agrilife Extension

Annual Reports


  • Agronomic: wheat


  • Soil Management: general soil management


    A study performed over the 2015/2016 wheat growing season showed that a producer could benefit from reducing nitrogen (N) fertilizer inputs based upon and deep profile soil test for residual nitrate (NO3) N. However, recovery of NO3-N was only 100% efficient to the 12” depth at this single site, contrasting with 24” recovery in warm season crops. Questions raised by the results prompted refinement of the treatment structure in year two (2016/2017) to determine whether inefficiency of overall N uptake was due to poor recovery of NO3-N from the soil or due to losses of surface applied, top-dress fertilizer.

    Project objectives:

    • Perform two studies in consecutive years on wheat recovery of residual N as measured by the deep profile soil test.
    • Communicate results of studies to producers in outreach events to encourage adoption of this conservation measure to reduce N fertilizer inputs.
    • Project goals refined in year two to work with two additional farmers to answer questions regarding efficiency of soil NO3-N uptake vs. surface applied fertilizer at Feekes growth stage 5
    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.