Life-cycle assessments (LCAs) of switchgrass (Panicum virgatum L.) grown for bioenergy production require data on soil organic carbon (SOC) change and harvested C yields to accurately estimate net greenhouse gas (GHG) emissions. To date, nearly all information on SOC change under switchgrass has been based on modeled assumptions or small plot research, both of which do not take into account spatial variability within or across sites for an agro-ecoregion. To address this need, we measured change in SOC and harvested C yield for switchgrass fields on ten farms in the central and northern Great Plains, USA (930 km latitudinal range). Change in SOC was determined by collecting multiple soil samples in transects across the fields prior to planting switchgrass and again 5 years later after switchgrass had been grown and managed as a bioenergy crop. Harvested aboveground C averaged 2.5± 0.7 Mg C ha^-1 over the 5 year study. Across sites, SOC increased significantly at 0?30 cm (P=0.03) and 0?120 cm (P=0.07), with accrual rates of 1.1 and 2.9 Mg C ha^-1 year^-1 (4.0 and 10.6 Mg CO₂ ha^-1 year^-1), respectively. Change in SOC across sites varied considerably, however, ranging from -0.6 to 4.3 Mg C ha^-1 year^-1 for the 0?30 cm depth. Such variation in SOC change must be taken into consideration in LCAs. Net GHG emissions from bioenergy crops vary in space and time. Such variation, coupled with an increased reliance on agriculture for energy production, underscores the need for long-term environmental monitoring sites in major agro-ecoregions.

Management of switchgrass for bioenergy and forage share some commonalities, of particular interest in bioenergy crop production is: (1) rapid establishment of switchgrass to generate harvestable biomass in the seeding year, (2) highly efficient management of soil and fertilizer N to minimize external energy inputs, and (3) harvest management to maximize yields of lignocellulose. Bioenergy cropping may entail management for multiple services in addition to biomass yield including soil C sequestration, wildlife habitat, landscape management, and water quality protection. Management is a critical factor especially as land classified as marginal or idle land will be emphasized for bioenergy production to reduce conflicts with food production. Marginal land may also be more risky. To date, there has been no long-term commercial production of switchgrass on a large scale and there is little in the way of hands-on, practical farm experience with switchgrass managed as a bioenergy crop. In this chapter, we lay out the key best management practices for switchgrass as a bioenergy crop including establishment, soil fertility, and pest management.

Switchgrass (Panicum virgatum L.) is being developed as a biofuel feedstock for the United States. Efficient and accurate methods to estimate switchgrass biomass feedstock supply within a production area will be required by biorefineries. Our main objective was to determine the effectiveness of indirect methods for estimating biomass yields and composition of switchgrass fields. Indirect measurements were conducted in eastern Nebraska from 2003 to 2007 in which switchgrass biomass yields were manipulated using three nitrogen rates (0 kg N ha^-1, 60 kg N ha^-1, and 120 kg N ha^-1) and two harvest periods (August and post-killing frost). A modified Robel pole was used to determine visual obstruction, elongated leaf height, and canopy height measurements. Prediction models from the study showed that elongated leaf height, visual obstruction, and canopy height measurements accounted for >91%, >90%, and >82% of the variation in switchgrass biomass, respectively. Regression slopes were similar by cultivar (?Cave-in-Rock? and ?Trailblazer?), harvest period, and across years indicating that a single model is applicable for determining biomass feedstock supply within a region, assuming similar harvesting methods. Sample numbers required to receive the same level of precision were as follows: elongated leaf height

The Agricultural Land Management Alternatives with Numerical Assessment Criteria (ALMANAC) model, originally developed and tested in Texas, needs to be tested for switchgrass (Panicum virgatum L.) simulation in more northerly locations. The Northern Great Plains of the U.S. has regionally adapted native populations of switchgrass and has excellent potential for growing switchgrass as a biofuel crop. The objective of this study was to adjust switchgrass parameters (potential leaf area index (DMLA) and degree days to maturity (PHU)) for northern sites and populations and to validate the model against switchgrass data from diverse sites in this region. Three or 4 years of measured yield data were used from a ten field sites in North Dakota (ND), South Dakota (SD), and Nebraska (NE). ALMANAC realistically simulated mean annual switchgrass yields ranging from means of 4.75 to 9.13 Mg ha^-1. Mean simulated yields were within 3%, 15%, and 9% of mean measured yields for NE, SD, and ND, respectively. Sensitivity analysis with temperature and rainfall demonstrated variable responses of potential yields depending on whether season duration, soil water, or soil nitrogen was the limiting factor at a site. ALMANAC shows promise as a useful tool for switchgrass evaluation and management in the northern Great Plains and in similar latitudes with low rainfall such as the East European Plain.

The feedstock characteristics of the conversion platform will influence the optimal harvest and post harvest management practices for switchgrass. However, many of the harvest management practices are tied to plant phenology and will be similar across platforms. Proper harvest and storage of switchgrass will help provide a consistent and high-quality feedstock to the biorefinery. Bioenergyspecific switchgrass strains are high-yielding and in most cases can be harvested and baled with commercially available haying equipment. Many options are available for packaging switchgrass for storage and transportation, but large round bales or large rectangular bales are the most readily available and are in use on farms. Large round bales tend to have less storage losses than large rectangular bales when stored outside, but rectangular bales tend to be easier to handle and load a truck for transport without road width restrictions. Although there is limited large-scale experience with harvesting and storing switchgrass for bioenergy, extensive research, as well as a history of harvesting hay crops for livestock in many agroecoregions, makes harvesting and preserving switchgrass for bioenergy feasible at the landscape scale.

Obtaining parasites from mammals that are collected during surveys or bioinventories is time-consuming, and in the past such collections have rarely been made. Parasites and other symbionts are important components of the biology of the host, however, and must be sampled for a complete picture of its ecology and other aspects of its life history. For example, work on parasite diversity and biogeography of mammals in Bolivia (Gardner and Duszynski 1990; Gardner 1991: Gardner et al. 1991; Gardner and Campbell 1992a, 1992b) could not have been accomplished without proper collections of the parasite and symbiont fauna of the hosts.

Many researchers are reluctant to assign one or two persons from a field crew to process parasites from mammals when the specimens and associated data are considered "auxiliary" or "collateral." The most efficient and cost-effective method of obtaining data on the parasite fauna of a host group, however, is to collect the parasites when mammals are being processed in the field. Examples of the types of data that may be obtained when a host is collected are prevalence, intensity of infection, and distribution of parasites in or on individuals and through populations of hosts.

Studies of the systematics and ecological characteristics of hosts and parasites require proper identification of both groups. If the parasites associated with a host are not collected and preserved properly, species-level diagnostic characters (i.e. morphological characters) will almost certainly be destroyed; in addition, improper preservation of parasite material will severely limit studies based on intact DNA molecules of those parasites.

Problems with identification of correct hosts may occur when parasites accidentally transfer from one host to another at the time of collection. Anthropogenic host-transfer can occur anywhere and is difficult to avoid in the field. For example, ectoparasites from one host may remain in a trap after the animal is removed. Those parasites may then transfer to another host of a different species at the same or a different collecting locality. Anthropogenic host-transfers occur even more frequently when hosts are placed in a killing jar that has not been cleaned completely after each use.

In this appendix, I outline methods for collecting parasites that maximize the amount of morphological and molecular information available from each parasite obtained. The procedures are designed to minimize the likelihood of mistakes in recording data due to anthropogenic host-transfers. My collaborators--Dr. Robert L. Rausch, Ms. Virginia Rausch, Dr. Terry L. Yates, and Dr. Sydney Anderson--and I have been collecting parasites in the field for more than 25 years. The protocols I present here have evolved considerably over that time and are based on our collective experience. Additional information on collecting techniques is presented in Anderson (1965) and Pritchard and Kruse (1982).

Data are collected in the field laboratory in assembly-line fashion, with different individual researchers in the field crew assigned to different tasks. Every part of every animal that is collected is processed in some way. Because of the possibility of contracting various viral diseases from handling wild-caught mammals, I recommend that surgical gloves and lab coats be worn during all laboratory procedures.

Fertilizer nitrogen is necessary for the efficient production of grain crops throughout the midwest. Farmers have recognized this need by tremendous increases in nitrogen consumption duhng the past decade.

Fertilizer nitrogen where needed for optimum yield usually increases slightly the total water used by the crop. The water required in making this optimum yield, however, is used a good deal more efficiently than where nitrogen is omitted. Nebraska studies on fertilizer economy have demonstrated nitrate leaching losses in some cases, especially serious on sandy soils of low water holding capacity and with irrigation. Strong circumstantial evidence also suggests denitrification of nitrate leached into the subsoil of some fine-textured subsoil types and resultant escape of elemental nitrogen gas.

In other cases, ammonia volatilization losses have proved serious, particularly with surface broadcasting of products containing or producing ammonium ion on neutral to alkaline soils. Magnitude of ammonia evolution is accentuated by drying conditions and by surface residue where nitrogen carriers are applied in solution form. Loss by volatilization is reduced greatly as the fertilizer is mixed immediately with the soil.

Summer sidedressing of fertilizer nitrogen for row crops, regardless of chemical form, has usually proved superior to fall or spring applications. This superiority has been especially apparent at the lower application rates. Not only has this been noticeable in the year of application, but the carryover nitrogen effect has been greater than with earlier application times. Thus, losses are minimized by delaying application to a time when crop roots are actively absorbing nitrogen from the soil.

In getting the most out of fertilizer nitrogen in grain crops, soil incorporation of the fertilizer and delayed application time seem in order.

The first year of the Food Preservation project aims to teach 4-H Club girls how to can fruits and vegetables. It is not only fun to can but there is a satisfaction in knowing that you are saving foods which will help to keep the family fit. Start canning as soon as there is something to can. You will see by the following list that canning direction are found in problem II.

This 4-H circular is a list of the mailings that need to be sent and the schedule used to send them.