Cover Crops and No-till in the I-States: Non-Permanence and Carbon Markets

Emerging voluntary carbon markets are attracting lots of attention in US agriculture, to the extent that agriculture carbon credits are usually referred to as the new cash crop. In essence, large companies would purchase carbon credits from multiple sources, including agriculture, to achieve their net zero emission goals. Farmers and ranchers would implement conservation practices that sequester carbon or provide other environmental benefits in exchange for compensation in cash or carbon credits depending on the carbon program. However, not all conservation practices are able to generate carbon credits

Land tenure, agri-environmental policy, and conservation practice use in Iowa

This dissertation broadly looks at farmers\u27 use of agricultural practices that affect water quality in Iowa. Primary themes across these three studies include (1) farmers\u27 willingness to use conservation practices that can improve soil health and water quality, (2) the effects of agri-environmental policy on adoption of conservation practices, and (3) the effects of land tenure on farmers\u27 use of inputs and conservation practices. Chapter 2 examines whether cost-share programs – which pay farmers to use a specific conservation practice – have had the desired effect of increasing cover-crop use in Iowa. Using a matching estimator, I conclude that cost-share recipients plant cover crops on an additional 15% of their farmland than they would have in absence of payment. In chapter 3, I study how landowner characteristics affect the use of conservation practices. The chapter focuses on whether leasing versus operating owned farmland decreases the use of conservation practices. I find that cover crops, buffer strips, and ponds/sediment basins are used at lower rates on rented farmland than on owner-operated farmland. However, no-till is used at a higher rate on rented farmland compared to owner-operated farmland. I also find that non-operator landowners have practices on their farmland at lesser rates than do landowners who currently farm. Chapter 4 uses data envelopment analysis and a panel of farms to estimate an efficient input-output frontier for corn production and calculate farms\u27 efficiencies. I then evaluate how productivity has changed over time and whether efficiency differs by farm size and land tenure. Technical efficiency increased between the first half of the period (2011-2014) and the second (2015-2018). Additionally, I find that larger farms are more technically efficient than smaller farms, and fully rented farms more technically efficient than fully owner-operated farms

Cover Crop Cost-Share Programs in Iowa: Do They Work?

Farmers often use cover crops for their soil health benefits. However, the benefits of cover crops go beyond the farm, as they have been shown to reduce nutrient pollution from fields to waterways through leaching or runoff. As such, cover crops have been extensively promoted as a way to improve Iowa’s water quality. However, as of 2017, cover crops were used on only 4% of Iowa cropland (see figure 1)

Do cost-share programs increase cover crop use? Empirical evidence from Iowa

Cover crops have been shown to have both on-farm and water quality benefits. However, the use of cover crops in Iowa remains subdued, in part due to the implementation costs faced by farmers. In this paper, we test the hypothesis that monetary incentives through cost-share programs are effective at increasing the amount of farmland planted to cover crops in Iowa, using a propensity-score matching estimator. Combining data from a unique cover crop survey of 674 farm-operator respondents and the 2012 Census of Agriculture, we find that cost-share payments induced an 18 percentage-point expansion of the cover crop area beyond what would have been planted in absence of the programs, for the farmers who participated in cost-share programs. In addition, at least two-thirds of the payments funded acres that would not have been planted without cost share. We also calculate farmers’ net returns to using cover crops with a partial budget analysis and estimate that the combined public and farmer cost of avoiding one pound of nitrogen pollution through cover crops is between $1.72 and$4.69 per pound, with farmers undertaking 70% of this cost through net losses. Overall, cost share for cover crops has been a relatively low-cost method to reduce nitrogen pollution to waterways in Iowa

Pervasive Disadoption Substantially Offsets New Adoption of Cover Crops and No-Till

Using data from the 2012 and 2017 U.S. Census of Agriculture, Sawadgo and Plastina (2022) summarized regional trends of adoption and disadoption of cover crops and no-till in the United States by Farm Resource Region (USDA, 2000) and highlighted the impact of large-scale disadoption in net adoption of conservation practices. They found that cover crops and no-till area increased by 5.0 and 7.9 million acres across the 48 contiguous states of the United States, respectively, between 2012 and 2017. However, in the absence of disadoption in counties with net attrition in area, cover crop and no-till area could have been 0.9 and 5.2 million acres higher, respectively, totaling 5.9 and 13.1 million acres in 2017.This article is published as Plastina A., Sawadgo W., Okonkwo E. "Pervasive Disadoption Substantially Offsets New Adoption of Cover Crops and No-Till". Choices 39 (2024). Available Online at https://www.choicesmagazine.org/choices-magazine/submitted-articles/pervasive-disadoption-substantially-offsets-new-adoption-of-cover-crops-and-no-till.JEL Classifications: Q15, Q2

Drivers of Profit Inefficiency in Iowa Crop Production

In this paper, we use data envelopment analysis and a panel of Iowa farms to evaluate profit inefficiency in corn and soybean production. We find that farms have, on average, profit inefficiency scores of 89.4% in combined corn and soybean production, suggesting that profit could be increased by 89.4% if farms eliminated technical and allocative inefficiencies. Overall, profit efficiency improved from 2011 to 2018, a period generally characterized by decreasing farm net worth. Moreover, while factors such as farm size and operator age affect technical inefficiency, these variables do not have a significant effect on profit inefficiency, while farms’ net worth per acre and crop insurance indemnity payments positively affect profit inefficiency. Land tenure does not have a significant effect on technical or profit inefficiency

What drives landowners’ conservation decisions? Evidence from Iowa

Conservation practices such as no-till and cover crops have been shown to have on-and off-farm benefits. However, underinvestment may occur when benefits of a practice do not go to the provider. A commonly cited barrier to conservation-practice adoption in agriculture is farmland-rental arrangements where tenants may not reap the benefits of conservation investments, resulting in lower adoption rates on leased land than on owner-operated fields. This issue is especially important since more than 40% of US farmland and more than half of Midwestern farmland is now rented from others. This paper examines the factors driving landowners’ decisions to adopt four key conservation practices–no-till, cover crops, buffer strips, and ponds/sediment basins–using a statistically representative survey of Iowa landowners contrasting from the common datasets that focus on farm operators. Our results show that no-till and cover crops are used on 27% and 4% of Iowa farmland in 2017, respectively. We find that to the conventional wisdom that adoption is lower on rented land only applies to the use of cover crops, buffer strips, and sediment basins, but not for no-till. In fact, our results show the adoption rate of no-till is higher on leased land than on owner-operated land. This puzzle is mainly driven by the fact that part-time farmers have far less no-till on their owner-operated land than do other types of farmers, which could be because full-time farmers and renters use no-till as a timesaving technique. Also, no-till is heavily adopted in western Iowa, likely as a way to reduce wind erosion on loess-hill soils. Furthermore, we find that landowners are open to incentivizing the adoption of cover crops on their land by helping tenants pay part of the planting costs for cover crops but not by extending the length of rental agreements. In particular, those who currently own no-tilled land are more willing to help their tenants finance cover crops or offer longer leases than those who do not own no-tilled land. Finally, our results show that half of landowners would be willing to increase the area of their land under conservation practices, if they could receive conservation-related tax credits or deductions

Partial Budgets for Cover Crops in Midwest Row Crop Farming

This study uses partial budgets to assess the annual net private economic returns to cover crop use in Midwest row crop farms. Data were compiled through an online survey to farm operators that manage production systems with and without cover crops. The average net returns to cover crops terminated with herbicides followed by corn was negative, but the average net return to cover crops terminated with herbicides followed by soybeans was positive. Cost-share payments tend to be insufficient to cover all private costs associated with cover crop use, but are a critical incentive to support this practice

Long term biochar effects on corn yield, soil quality and profitability in the US Midwest

Corn production in the US Midwest has the potential to generate a large amount of crop residue for bioenergy production. However, unconstrained harvesting of crop residues is associated with a long-term decline in soil quality. Biochar applications can mitigate many of the negative effects of residue removal but data and economic analyses to support decision making are lacking. To explore sustainable and profitable practices for residue harvesting in central Iowa we used 11 years of soil, crop yield, and management data to calibrate the Agricultural Production Systems sIMulator (APSIM) biochar model. We then used the model to evaluate how different biochar types and application rates impact productivity and environmental performance of conventional corn and corn-soybean cropping systems in Iowa under different N fertilizer application rates and residue harvesting scenarios. A cost-benefit analysis was also employed to identify the economically optimal biochar application rate from both producer and societal perspectives. Modeling results showed for both continuous corn and corn-soybean rotations that as biochar application rate increased (from 0 to 90 Mg ha-1) nitrate leaching decreased (from 2.5 to 20 %) and soil carbon levels increased (from 8 to 115 %), but there was only a small impact on corn yields (from –2.6 to 0.6 %). The cost-benefit analysis revealed that public benefits, evaluated from decreased nitrate leaching and increased soil carbon levels, significantly outweighed the private revenue accrued from crop yield gains, and that a biochar application rate of 22 Mg ha-1 was more cost-effective (per ton) compared to higher biochar rates. Overall, this study found that applying biochar once at a rate of 22 Mg ha-1 allows for the sustainable annual removal of 50% of corn residue for 32 years, is profitable for farmers even with minimal impact on grain yield, and beneficial to society through reduced nitrate leaching and increased soil organic carbon levels