Estimating Percent Residue Cover Using the Line-Transect Method

Leaving crop residue on the soil surface is one of the easiest and most cost-effective methods of reducing soil erosion. Research in Nebraska and other midwestern states has shown that leaving as little as 20 percent of the soil surface covered with crop residue can reduce soil erosion by one-half of what it would be from residue-free conditions. Greater amounts of residue cover will further reduce erosion. Many Conservation Plans specify crop residue management or residue left on the soil surface as the primary erosion control method. Generally, the amount of cover required after planting ranges from 30 percent to as much as 85 percent. Thus, it is important to accurately determine percent residue cover to verify effective erosion control and compliance with a Conservation Plan. Residue cover cannot be estimated merely by looking across a field. Such estimates, often attempted from the road or edge of the field, grossly overestimate the actual amount of cover. Accurate estimates of residue cover can only be obtained from measurements taken within the field, while looking straight down at the soil and residue. Crop residue management, or leaving residue on the soil surface, is the most cost-effective method of reducing soil erosion available to Nebraska farmers. Accurate measurements of percent residue cover are needed to determine if enough cover is present to adequately reduce erosion and to comply with a Conservation Plan. The line-transect method is one of the easiest and most accurate methods of determining percent residue cover

G1564 Manure Incorporation and Crop Residue Cover — Part II: Fine-Tuning the System

How injector/applicator spacing, tire spacing, field speed, and other factors influence the amount of residue cover reduction after manure incorporation. Manure incorporation represents a conflict between best management practices for soil erosion control and manure management. Manure should be incorporated into the soil for odor control, maximum availability of nutrients, and control of potential manure runoff. However, for maximum soil erosion control, the soil and crop residue should remain undisturbed. These two best management practices must be balanced since disturbing the soil and residue for manure incorporation, either with conventional tillage implements or equipment specifically designedfor manure application, reduces the residue cover remaining for erosion control. The companion NebGuide, Manure Incorporation and Crop Residue Cover — Part I: Reduction of Cover (G1563), presents results from a field study conducted at the University of Nebraska– Lincoln Haskell Agricultural Laboratory at Concord to evaluate the degree of residue cover reduction caused by soil-engaging components typically used with tank spreaders and towed hose systems to apply liquid or slurry manure. Ranges of values are given for the percentage of the initial residue cover that could be expected to remain after the operation of chisel and sweep manure injectors, disk and coulter applicators and a tandem disk. This NebGuide discusses how injector/applicator spacing, tire spacing, field speed, and other factors influence the amount of residue cover reduction. Much of this information is based on experience and field observations and is intended to help livestock producers select and operate manure application/ incorporation equipment to maximize residue cover and erosion control

Estimating Percent Residue Cover Using the Line-Transect Method

Leaving crop residue on the soil surface is one of the easiest and most cost-effective methods of reducing soil erosion. Research in Nebraska and other midwestern states has shown that leaving as little as 20 percent of the soil surface covered with crop residue can reduce soil erosion by one-half of what it would be from residue-free conditions. Greater amounts of residue cover will further reduce erosion. Many Conservation Plans specify crop residue management or residue left on the soil surface as the primary erosion control method. Generally, the amount of cover required after planting ranges from 30 percent to as much as 85 percent. Thus, it is important to accurately determine percent residue cover to verify effective erosion control and compliance with a Conservation Plan. Residue cover cannot be estimated merely by looking across a field. Such estimates, often attempted from the road or edge of the field, grossly overestimate the actual amount of cover. Accurate estimates of residue cover can only be obtained from measurements taken within the field, while looking straight down at the soil and residue. Crop residue management, or leaving residue on the soil surface, is the most cost-effective method of reducing soil erosion available to Nebraska farmers. Accurate measurements of percent residue cover are needed to determine if enough cover is present to adequately reduce erosion and to comply with a Conservation Plan. The line-transect method is one of the easiest and most accurate methods of determining percent residue cover

Thin film optical filter fabrication and characterization

Thin film coatings have a large number of applications. For example, one can eliminate unwanted reflection on a photographic lens or unwanted wavelengths of light in optics experimentation. The fabrication and characterization of films whose refractive indices can be arbitrarily modulated (‘Rugate Filters’) is an ongoing exploration in materials science1,2. Therefore, calibrating a process which can manufacture such films is a relevant pursuit in forwarding such explorations. Reactive magnetron sputter deposition is a commonly used technique for the productions of thin films3,4. This technique steadily flows reactive gas (RG) into a vacuum chamber in which an electric field has been established. The RG is then ionized by the electric field which causes it to bombard a solid target placed inside the chamber. Many of the atoms which are displaced by the ionized gas further travel towards an adjacent substrate (Figure 1). Ideally, this occurs in such a way as to deposit the newly formed molecule on the surface a glass slide. In our case the RG, N2, and O2 were intended to deposit Si3N4 and SiO2 whose indices of refraction are respectively high and low (Figure 4). Reproducibility of this contrast is essential in the fabrication of the desired optical devices. In order to determine that these intended reactions occurred in a reproducible way, the thickness and refractive index of the films where calculated from the Transmission Spectra of the films

CC278 Farm Energy Tips - Use Energy Wisely - Tractor Ballasting

Campaign Circular 278: This is about tractor ballasting and how and when to do so

CC278 Farm Energy Tips - Use Energy Wisely - Tractor Ballasting

Campaign Circular 278: This is about tractor ballasting and how and when to do so

CC270 Fuel Storage

Campaign Circular 270: This circular is about fuel storage, fuel caps, filler caps, tank colors, tank locations, fuel quality, fuel loss examples, and recommendations. At the head of the title it has Farm Energy Tips...Use Energy Wisel

Second hyperpolarizability of carbon tetrachloride

Although present theories of nonlinear optics agree with observed behavior in simple atoms such as helium, more complex molecules containing many electrons, such as carbon tetrachloride (CCI4), cannot consistently be described by theory. Through experimental analysis of nonlinear materials, a new, more sophisticated model for describing their properties could be realized. The purpose of our experiment was to measure the nonlinear behavior of the second harmonic signal generated from CCI4 and to compare the results with the prediction by the CCSD(T) molecular model

G83-683 Quality Concrete for Swine Facilities

This NebGuide discusses the major items to consider when using concrete for swine facilities to help assure that quality concrete is obtained. Concrete is widely used to construct swine production facilities. Versatility, durability, and relatively low cost are characteristics that make it ideally suited for floors, walls, foundations, pen dividers, and manure storage structures. With appropriate design, concrete can even be used for the building roof and feeders. There are, however, certain major items to consider to help assure quality concrete and years of reliable service regardless of the specific use