Kelly and Deborah Kettner operate a diverse farm in the Southern High Plains Region of Texas (Lamb and Parmer Counties). The Southern High Plains is characterized by large areas of open plains on an elevated plateau at 4,600 ft in the northwest, gradually decreasing to 2,600 ft in the southeast. Nearly level, gentle slopes dominate the landscape. Farmland makes up the largest portion of this area. The farming operation involves approximately 4,000 acres. The irrigated portion is approximately 3,000 acres, and dryland operations utilize the other 1,000 acres. The soils are generally deep and well drained, and are developed in eolian (wind-derived) deposits. Amarillo fine sandy loam soils (TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Aridic Paleustalfs) are found on many of the Kettner farm acres.
The goal for the entire property is to eliminate soil wind erosion and increase water holding capacity and water infiltration. The objectives of this goal is to increase microbial activity of soil and increase residue levels and no till crops for agricultural productivity. On irrigated acres, water conservation and nutrient efficiency are the goals including rotation with high residue crops and mix in low residue crops for diversity (i.e. cotton) as well as cover crops in between row crops. The objectives of this goal on irrigated acres is to reduce inputs, increase yields for increased economic returns, learning to incorporate feeder cattle and sheep to improve soil health when the cotton crop is grown, reduce irrigated acres, and consistently have a living root growing to feed soil microbes. On dryland acres, the goals are to reduce risk and increase flexibility in the agricultural operation with dryland acres and to leave crop and cover crop residues to reduce wind erosion and build soil health. The objectives of these practices are to have a diverse crop rotation with cover crops used as forage for the sheep and beef cattle and to use mixed species of cover crops after cotton for diversity. (See table 1 of full text pdf for additional detail)
Climate Change Impacts
The Southern High Plains area which encompasses Oklahoma and Texas has had an increase in average annual temperatures in recent decades (Kunkel et al., 2013; USGCRP, 2018). Hot periods are hotter and cold periods are warmer. While the current growing season is six days longer than during 1961-1990. Winters and springs are wetter, summers are drier, and drought and extreme precipitation events are more frequent. These trends are expected to continue based on model simulations. In the 21st century, historically unprecedented warming is projected with increased extreme heat events. It is predicted that the number of days above 95o F and nights over 80o F will increase. Different climate models predict different amounts of increases. Higher temperatures will increase soil moisture loss and increase the intensity of naturally occurring droughts (Runkle & Sweet, 2017). Projected changes in precipitation are less clear, but more extreme precipitation events are expected. Heavy rains, flooding, drought and severe storms will become more frequent and intense (Kunkel et al., 2013) (Lengick, 2018).
Challenges & Opportunities
Climate change will present challenges and opportunities for accomplishing the management objectives of this project. The objective of increasing microbial activity across the entire farm will be facilitated by increasing residue levels from incorporating practices such as cover crops and no-till, as well as reduced use of chemicals and fertilizers. The challenges to accomplishing this objective will be maintaining effective weed control and soil fertility levels, impacted especially by the reduced use of chemical/nutrient treatments. But this reduction of treatments as well as use of no-till will also be a way to lower production costs and well as improve water-use efficiency.
Specifically, on dryland acres, the goal is to incorporate cover crops into the rotation (e.g., planting a cover crop in the fall following cotton harvest). There are grazing opportunities on the cover crops, but the producer faces challenges of method and timing of termination as well as the requirement for late fall rains to stimulate cover crop germination.
On irrigated acres, the management objective is to establish a rotation that includes high residue crops mixed with lower residue crops (such as cotton) for plant diversity, to utilize forage cover crops to incorporate animals for improving soil health. These are similar objectives to the dryland acres and face similar challenges such as timing of cover crops, increased water usage (for both animals and cover crops), and the requirement of moving animals between field paddocks. The opportunity is for grazing potential and cover crops allow for the reduced inputs of fertilizers and herbicide. (See table 3 of full text pdf for additional detail)
The Adaptation Workbook was used to identify some potential adaptation actions for this project, including:
- One tactic considered for the entire property is to plant different varieties of commodity crops with diverse harvest dates to widen the window of opportunity to plant cover crops. The approach or intent is to help manage crops to cope with warmer and drier conditions. A second tactic is to increase economic returns by reducing inputs (fertilizer/chemicals) and increasing yields. The approach for this tactic is improve soil health by keeping the soil covered to reduce weed pressure and increase microbial activity.
- For irrigated acres, a tactic is to incorporate feeder cattle and sheep to improve soil health before cotton crop is grown. This incorporation of livestock will improve soil health by adding manures to cropped fields. These animals also increase farm diversity and can increase economic returns.
- On dryland acres, the approach is to decrease wind erosion damage by keeping soils covered with residues from both the primary and cover crops, as well as using no-till or strip till to reduce soil disturbance.
(See Worksheet 4 of full text pdf for additional detail)
Several monitoring items were identified that could help inform future management, including: economic evaluations using input/output costs, yield trends of cotton with use of use of cover crops and livestock, and use of water sensors (meters) on irrigated acres to examine the amount of water being used and whether pre-irrigation is required for seed germination. (See Worksheet 5 of full text pdf for additional detail)