Physical Sciences and Mathematics Commons^™

The Effectiveness Of A New Mole Repellent For Preventing Damage To Lawns By Eastern Moles, Glenn R. Dudderar, Stacey Tellman, Dale K. Elshoff

Wildlife Damage Management Conference

A new product containing 65% castor oil with the trade name Mole-Med was evaluated for its effectiveness in repelling eastern moles (Scalopus aquaticus) from lawns. Seven lawns in southern Michigan during September, 1993 were selected as preliminary test sites, and the ridges over mole tunnels in the lawns were flattened each day for 3 days. If some existing and new ridges were raised each day, the site was classified as having mole activity and continuing damage. The repellent was then applied according to label directions, and ridges above mole tunnels were flattened as described previously. If no tunnels …

Bat Exclusion Methods, William H. Kern Jr

Wildlife Damage Management Conference

This publication is intended to serve as a review of currently accepted methods of bat exclusion. Inappropriate house bat control methods are destructive to our decreasing bat populations and often cause additional problems for the building's owner or occupant. These problems include odor from dead bats, infestations of carrion-feeding flies, and increasing human and pet exposure to bats. Appropriate exclusion methods like winter structure modification for cave hibernating bats or one-way excluders using hardware cloth, plastic sheeting, or plastic birdnetting are the best ways to protect these beneficial wildlife species and correct situations where humans and bats come into conflict.

A Comparison Of Deer Hunter And Farmer Attitudes About Crop Damage Abatement In Michigan: Messages For Hunters, Farmers, And Managers, Peter A. Fritzell Jr., Donna L. Minnis, R. Ben Peyton

Wildlife Damage Management Conference

During the last 20 years several states have seen dramatic changes in the size of their white-tailed deer (Odocoileus virginianus) populations and also more frequent debates about how the deer resource should be managed. One central area of conflict between stakeholders involved in deer management is the issue of the lethal control of depredating deer, and how and when programs involving lethal control should be implemented. In the last decade, both Michigan farmers and deer hunters have organized special interest groups to express their dissatisfaction with deer population numbers, deer-caused crop losses, and/or the state's crop depredation control …

Ecosystem Management And Wildlife Management: Compatible Or Conflicting?, David C. Guynn Jr., Greg K. Yarrow

Wildlife Damage Management Conference

Examples of wildlife-human conflicts include deer-automobile collisions, disease transmission concerns, and damage to various commodities (e.g. agricultural crops, timber production). The extent of these problems is increasing at a time when American's attitudes are shifting emphasis from commodity production to concern for the environment. Ecosystem management has been proposed as a strategy to balance concerns for commodity production and the environment. Ecosystem management, unlike traditional natural resource management, will require management over large areas for long periods of time. This new philosophy of land management requires that the natural resource base be viewed in its entirety, and not as separate …

Evaluation Of The Yard Gard Ultrasonic Yard Protector For Repelling White-Tailed Deer, Paul D. Curtis, Christopher Fitzgerald, Milo E. Richmond

Wildlife Damage Management Conference

Ultrasonic devices are marketed for pest control because some manufacturers believe they possess properties aversive to animals. However, there is little evidence that ultrasound is more aversive to animals than is audible sound. In this study, we examined the efficacy of the Yard Gard ultrasonic device for deterring deer (Odocoileus virginianus) from feeding on apples. Four deer feeding stations were established at private residential properties with a history of deer damage to ornamental plants, so that control (A1 and B1) and experimental (A2 and B2) stations existed at each site. Apples were placed at each feeding station and …

Sample Design In The Finnish Agricultural Income Statistics, Paavo Väisänen

Conference on Applied Statistics in Agriculture

The Finnish Agricultural Income Statistics. published yearly by Statistics Finland, are based on a survey in which the data are collected from the farms in connection with taxation. The sampling design is stratified simple random sampling, in which Neyman allocation is used to calculate the sample sizes for the strata. The Farm Register is used as the sampling frame where variables such as region, production sector and arable land are available for stratification. The total incomes of farms from the previous survey serve as the allocation variable. Stratification and Neyman allocation rendered the estimates of most income variables more effective …

Mixed Models Approach To On-Farm Trials: An Alternative To Meta-Analysis For Comparing One Treatment To Possibly Different Controls, Peter M. Njuho, George A. Milliken

Conference on Applied Statistics in Agriculture

The estimator of effect size, the sample mean difference divided by the sample standard error of the difference is studied in the context of mixed models and is related to the analysis of on-farm trials. A single treatment is compared against possibly different controls using a completely randomized design on each farm. A lower (1-α)100% confidence limit on mean difference of the treatment and the average control is obtained. The best linear unbiased predictors (BLUPs) of the mean difference of the treatment and the individual controls as well as the lower (1-α)100% prediction limits are provided. The effect of omitting …

Using Tree Regression To Identify Nutritional And Environmental Factors Affecting Sugarcane Production, Kenneth M. Portier, David L. Anderson

Conference on Applied Statistics in Agriculture

A prediction function is developed for sugarcane yield using preplant soil nutrition levels, cultivar, and soil type. A tree regression approach is used because the resulting function encompasses the complexity of response between yield, multiple nutrients and other factors, while handling large amounts of data and providing information useful in the development of fertilizer and other production recommendations. Data collected from 148 control plots of experiments performed on commercial fields in the Everglades Agricultural Area of Florida are used to illustrate the method.

Step-Stress Testing In Agricultijre, Imad H. Khamis, James J. Higgins

Conference on Applied Statistics in Agriculture

Step-stress testing has been used for a munber years in engineering. An item is placed on test for a specified period of time. If it does not fail in that time, the stress is increased. This process is repeated for a specified number of stress levels until the item fails. In agriculture, animals or plants may be the test items and dosage of a chemical, amount of fertilizer, temperature, etc, the stress variable. In this paper we suggest several potential applications of step-stress testing in agriculture and present inferential procedures for observations that are distributed exponentially.

Two-Factor Agricultural Experiment With Repeated Measures On One Factor In A Complete Randomized Design, Armando Garsd, María Del C. Fabrizio, María V. López

Conference on Applied Statistics in Agriculture

A typical agricultural experiment involves comparisons of several treatments at different points in time. The ensuing lack of independence between observations of the same experimental unit may then impair the attainment of statistical significance by the standard analysis of variance, and calls for the application of more powerful methods. This paper addresses one such method, the so-called two-factor experiment with repeated measures on one factor. We discuss the adequacy of this model in the context of three concrete examples drawn from agricultural experimentation.

Sequential Analysis Of Agricultural Experiments, Armando Garsd, María V. López, María Del C. Fabrizio

Conference on Applied Statistics in Agriculture

Interim monitoring of accumulating data has been widely used in clinical trials, but it has not received the same attention in agricultural experimentation. The methodology, however, can be a useful tool in agronomic trials designed to find better production techniques or optimal animal treatments at low cost, plus the possible economic advantages resulting from correct early decisions. These sequential procedures for testing hypothesis with available data in successive periods of time dictate termination of the experiment when a significant difference is detected, or otherwise continuation of the experiment to the end of the stipulated time or until all the planned …

Spatial Analysis Of Grasshopper Density As Influenced By Anthropogenic Habitat Changes, Bahman Shafii, William J. Price, Dennis J. Fielding, Merlyn A. Brusven

Conference on Applied Statistics in Agriculture

The rangeland environment in southern Idaho has been heavily impacted by human activities. Invasion by exotic plant species, frequent fires, grazing pressure, and other ecological disturbances have greatly affected the structure and dynamics of grasshopper populations. Quantification of spatial patterns of grasshopper density and species composition is important in order to determine their influence on grassland ecosystems, as well as evaluating managerial decisions concerning vegetation manipulations, grazing practices, and spraying programs. A spatial statistical approach to modeling the heterogeneity of grasshopper populations is presented, and the impact of vegetation and grazing treatments on grasshopper density is investigated. Empirical applications are …

A Classification Of Unreplicated Factorial Experiments For Use With The Analysis Of Deterministic Simulation Models, J L. Willers, B. T. Vinyard

Conference on Applied Statistics in Agriculture

Deterministic simulation models are important in agricultural applications and their use is becoming increasingly common. Therefore, statistical procedures that interpret the output and evaluate the performance of deterministic models are necessary. The fact that deterministic computer simulation experiments cannot be replicated provides opportunities for using several procedures applicable to unreplicated factorial experiments. We discuss a classification scheme that selects the correct technique for most deterministic simulation experiments. The value of these techniques is their capability to estimate the experimental error variance for unreplicated computer experiments. Using these estimates of error, model developers and practitioners can more thoroughly analyze their deterministic …

Estimation Of And Adjustment For Residual Effects In Dairy Feeding Experiments Utilizing Changeover Designs, Ramon C. Littell, Charles J. Wilcox, H. H. Van Horn, A. P. Tomlinson

Conference on Applied Statistics in Agriculture

A procedure is presented which demonstrates estimation of and adjustment for residual effects in changeover designs. The method utilizes all data collected in an experiment by including treatments imposed on animals prior to initiation of data collection. Estimation is achieved via general linear models. An example is given of a nutrition experiment conducted with dairy cattle. Such analyses should increase efficacy of changeover designs and reduce concern by researchers about biased estimates of direct effects which could result from residual effects. Methods from popular computer programs for estimating direct effect treatment means are compared. Practical problems encountered in computing standard …

Issues In Analysis Of A Long-Term Integrated Pest Management Field Study, J. R. Alldredge, F. L. Young

Conference on Applied Statistics in Agriculture

A team of 14 scientists conducted a 6-year, 16-ha, integrated pest management field study in the dryland wheat production area of the Pacific Northwest. Objectives were to develop a profitable crop production system that controls weeds effectively and reduces soil erosion. Farm-size machinery was used to till, plant, and harvest crops grown in either a continuous wheat (Triticum aestivum L.) sequence or a 3-year crop rotation of winter wheat-spring barley (Hordeum vulgare L.) -spring pea (Pisum sativum L.) in conservation and conventional tillage systems. Main plot factor levels were two tillage systems and three …

Bayesian Inference On Variance Components In Generalized Linear Mixed Models: An Evaluation Of Different Methods, Robert J. Tempelman

Conference on Applied Statistics in Agriculture

Generalized linear mixed models are now popular in the animal breeding and biostatistics literature as these models allow inference on fixed and random effects for the exponential family of data distributions. In animal breeding, particular attention is directed towards variances of the random effects. We investigate three methods for marginal inference on variance components in binary data, including (1) the conventional expectation-maximization (EM) type algorithm, (2) Laplace's method, and (3) "exact" Gibbs sampling methods. A simulation study involving probit animal models was used to compare the modal estimates computed under the three methods. It was found that EM estimates were …

Variance As A Factor Effect In Interdisciplinary Studies Of Agricultural Systems, Cathryn S. Miller, Dawn M. Vanleeuwen, Jill Schroeder, Mike Kenney

Conference on Applied Statistics in Agriculture

Studies of interrelationships among factors typically focus on factor effects related to the mean response. In some instances, response variances, as well as, or even rather than, response means, may be affected by the factors under consideration. In this paper, generalizations of Levene's test and the Jackknife test to two-factor experimental designs are studied via simulation studies to assess their ability to identify differences in the variance as an interaction effect or as a factor main effect. These tests are then applied to a particular example where relationships between chile plants and two prominent pests of chile plants -nematodes and …

Predicting The Date Of First Catch Of The Corn Earworm, Helicoverpa Zea, In Central U.S., J. H. Matis, S. Yang, N. Castiaux, J. K. Westbrook, K. R. Beerwinkle, J. D. Lopez Jr.

Conference on Applied Statistics in Agriculture

This paper develops predictive (or correlative) models for the date of first catch of the com earworm, Helicoverpa zea, as a basis for identifying biotic and abiotic factors that influence dispersal and migration. Data described in Goodenough et al. (1988, J. Econ. Entomol.) on the catch of H. zea gathered at over 150 sites predominantly in the central U.S. from 1983 to 1986 are analyzed. The dependent variables, Y₁ and Y₂, are date of first meaningful catch and date when cumulative catch exceeds 5, respectively; the independent variables are latitude, longitude and elevation of the site. …

Sampling Schemes To Detect Very Low Concentrations, Terry C. Nelsen

Conference on Applied Statistics in Agriculture

Many mycotoxins and certain drug residues can be important at very low concentrations in feeds and foods. Government regulatory agencies establish maximum acceptance concentrations (Action Levels) to avoid proven effects of known toxins and provide Advisory Levels where effects are not yet well established. The Action Levels for the aflatoxins range from 5 to 300 ppb (ng/g) depending on the particular toxin and the intended use of the feed or food. Other naturally occurring mycotoxins, such as DON, zearalenones, and fumonisons, have advisory levels in the range of 1 to 5 ppm (j.A-g/g) . Chemotherapeutic agents in feeds must be …

Sampling Segments In An Area Frame With A Distance Threshold, M. Fuentes, F. J. Gallego

Conference on Applied Statistics in Agriculture

A simple random sample in an area frame usually gives a number of pairs of elements that are close to each other. These elements give redundant information since there is usually a high spatial autocorrelation at short distances. The efficiency of sampling is generally improved if we impose that the distance between two elements of the sample cannot be less than a certain threshold. However applying this restriction can introduce a significant perturbation of the sampling probability. Elements near the borders of the region are more likely to be selected. In the case of aligned sampling by repetition of a …

Covariance Analysis With A Covariate Interaction: An Example Of A Simple Linear Regression Comparison Technique, D. E. Palmquist, C. A. Stockwell

Conference on Applied Statistics in Agriculture

Many real data sets that would normally lend themselves to being analyzed by an analysis of covariance, have a covariate interaction present with one or more of the factors in the experiment. Because this violates the assumption of same-slope covariate effect across all treatments, an analysis of covariance should not be performed. The course normally taken when there is such an interaction is to derive regression equations for the dependent variable as a function of the covariate, at each level of the factor(s) being tested. A general linear model F-test can then be used to test whether there are any …

A Review Of Analysis Of Experimental Data, Roger Mead

Conference on Applied Statistics in Agriculture

Initial Assumptions, We assume that it is standard practice to base an initial analysis of experimental data on a linear model including terms for blocks, treatments and covariates. This produces a summary analysis of variance, indicating the major components of variation relative to the fitted model, and tables of means (one- or two-way) as indicated from the analysis of variances, with appropriate standard errors.

Editor's Preface, Table Of Contents, And List Of Attendees, James R. Schwenke

Conference on Applied Statistics in Agriculture

These proceedings contain papers presented in the seventh annual Kansas State University Conference on Applied Statistics in Agriculture, held in Manhattan, Kansas, April 23 through 25, 1995.

What Leading Alfalfa Growers Do To Produce Quality Hay, Jimmy C. Henning, Garry D. Lacefield, Buddy Sims

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is the highest quality forage legume crop grown in Kentucky and is the number one cash hay crop. Hay raised by Kentucky farmers has been recognized for its quality at local, state (state fair and Kentucky Alfalfa Conference), and national (American Forage and Grassland Council) hay contests. The testing records of the Kentucky Department of Agriculture also document the high quality alfalfa hay of Kentucky. However, little has been written about the farm practices used to produce high quality alfalfa hay in Kentucky. The current practices of top hay growers may be helpful in defining the options available to …

How To Make Your Alfalfa More Profitable, Clive Holland

Kentucky Alfalfa and Stored Forage Conference

As a perennial plant, alfalfa can be expected to continue to live and produce for an indefinite period of time. Why then do stands need to be replanted every few years? Is modern seed available today, weakened and unable to live up to the perennial label? What about yield? How does your stand measure up? Are you barely making the state average, or struggling to even meet this modest yield level?

The first harvest each spring can produce over 40% of the yield in a single growing season. Why is a stand slower growing in the spring than you would …

Role Of Alfalfa In Animal Diets, Jennifer L. Garrett

Kentucky Alfalfa and Stored Forage Conference

Alfalfa forage use has increased in all classes of livestock - dairy, beef, horses, sheep, and swine - during the last 40 years. The highest utilization of alfalfa by livestock is found in dairy cattle diets. Additionally, the use of alfalfa as a grazing crop has also undergone a considerable increase with the use of new grazing management techniques and the development of new grazing varieties.

Alfalfa's strength as a forage crop is its high nutritional value. Alfalfa is higher in protein, minerals, and net energy than grasses and small grains. High quality alfalfa also helps to promote intake, especially …

Saving Those Valuable Leaves During Haymaking, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

Field dry hay needs to be reduced from near 80% moisture to 20% or less to prevent spoilage during storage. Drying hay to safe baling moistures often takes several days. Sources of loss during forage harvest include mechanical losses such as mowing, conditioning, chopping, raking, packaging and handling as well as respiration and leaching. The general relationship between forage moisture concentration at harvest and losses during the field and storage phases is shown in Figure 1. Harvest losses are greatest for very dry forage and are low for very wet material like direct cut silage. However, the latter is subject …

Alfalfa As A Grazing Crop: Progress Continues, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

This makes the third consecutive year that I have talked about "Alfalfa as a Grazing Crop". At our XIII Kentucky Alfalfa, I, along with five other speakers, discussed several aspects of grazing alfalfa and all agreed that the concept had tremendous potential.

This past year I reviewed some of the discussion of our XIII Conference and shared some of the activities going on in research and educational programs throughout the region. In addition, I announced the date for a National Alfalfa Grazing Conference to be held in Nashville, Tennessee. The Conference was held July 29 and was a big success. …

Control Of Johnsongrass And Other Weedy Grasses In Alfalfa, Jonathan D. Green

Kentucky Alfalfa and Stored Forage Conference

Johnsongrass is considered one of the major weed species that infests alfalfa in Kentucky. Other weedy grasses such as large crabgrass, foxtails, barnyard grass, and fall panicum can also interfere with alfalfa production. Low infestation levels of these grasses may not create significant concern, but high infestation levels can result in reduced yield, alfalfa hay quality, and/or shorten the life of the stand.

Opportunities For No-Till Alfalfa In Kentucky, Jimmy C. Henning, Garry D. Lacefield, Andy Anderson

Kentucky Alfalfa and Stored Forage Conference

There is a rising interest in the use of alfalfa in pastures, especially for dairy cattle, beef stockers and as supplemental summer grazing for cows with calves. Kentucky has the land resource to support 2 million acres of alfalfa without reducing acres in cultivated crops. Acres of alfalfa seeded for pasture use would be in addition to the 350,000 acres presently used primarily for hay. However, these additional acres are rolling and erodible and therefore alfalfa should be established by no-till methods.