Comparison of Instructional Methods for Teaching Landscape Construction Techniques to Undergraduate Horticulture Students1

NACTA Journal, Jun 2004 by Henry, Paul H, Midden, Karen, Lieske, Earl

Abstract

A software program was created that could be used to familiarize undergraduate horticulture students with common landscape construction techniques. The objective of this study was to evaluate a prototype of this software by comparing its effectiveness to the more traditional type of instruction consisting of lecture and overheads. Students responded to both multiple-choice and graphic response (answer requires graphic representation of technique) questions in a pretest / posttest format. For both types of questions, students in the control (provided information by lecture) and treatment (provided information by software) groups significantly improved their scores on the posttest compared to the pretest. However, there were no significant differences between control and treatment groups on posttest scores. Results of this study indicate that the software program and lecture were equally effective in teaching students about common landscape construction techniques.

Introduction

Landscape construction involves the design, creation, and incorporation of non-plant elements such as walkways, retaining walls, bridges, and water features - into a landscape (Sauter, 1999). University horticulture programs can find it difficult, for several reasons, to meet the needs of their students with respect to training in landscape construction. Most importantly, courses in landscape construction are expensive to teach since they generally include a lab which requires a substantial input of costly materials and equipment. In addition, it can be hard to find academically trained professionals who have both a strong knowledge base and practical work experience in the field of landscape construction. Teaching the subject is challenging since, in most cases, a number of different approaches and many different types of materials can be used to complete a particular project.

Computer based instruction (CBI) has the potential to be a useful tool in teaching landscape construction, particularly in situations where it is not possible to offer a lab. Graphic capabilities of computers, in conjunction with sophisticated authoring software, allow construction processes to be depicted in a clear, step-by step manner which is difficult to simulate in a traditional lecture format. In addition, there is no doubt that CBI has the potential to be a cost-effective approach when compared to the cost of outdoor lab exercises (Rhodus and Hoskins, 1995).

A project was initiated in 2000 to develop a CDbased software program that could be used to instruct students in landscape construction techniques. The objective of this study was to evaluate a prototype of this software and compare its effectiveness, as a teaching tool, to the more traditional type of instruction consisting of lecture and overheads.

Materials and Methods

Creation of Images

Twenty-six landscape construction projects were selected and categorized under the headings of landforms, pavement, site structures, or water. Projects were selected because of their common use in the landscape construction industry. Elevation and plan views of each project were drawn within a five by five-inch area using a Bruynzeel (Netherlands) design pencil with an H quality lead. Details were drawn to scale and subsequently transferred to Grafix film sheets (Grafix Plastics, Cleveland, OH) using Rapidograph pens and Ultradraw quick drying black India ink. (Chartpak Inc., MA).

Completed drawings were scanned into Adobe Photoshop (Adobe Systems, San Jose, CA) as highlevel line art with a resolution of eight hundred dpi (distributed protocol interface). Drawings were subsequently converted to grayscale at a resolution of seventy-two that provided good contrast between black and white areas of the drawings.

Delivery Platform

Macromedia Directory (Macromedia Inc., San Francisco, CA) was chosen as the delivery platform. Scripts detailing each step of the construction process were written for each detail and recorded with a Shure 57 microphone (Shure Inc., Evanston, IL) into a Digi ProTools (Macromedia Inc., San Francisco, CA) system on a Mac G4. Recordings were subsequently cleaned up using a compressor and EQ and taken into SoundEdit 16. (Macromedia Inc., San Francisco, CA). SoundEdit was used to break up the audio into separate steps, convert the audio to Shockwave audio (Macromedia, Inc., San Francisco, CA) and insert the points that trigger the tags in Director. Labels that accompanied drawings were timed to gradually fade in as a particular aspect of a drawing was being discussed on the script.

Data Collection and Analysis

The experimental population consisted of fortytwo junior and senior students enrolled in the landscape horticulture program at Southern Illinois University Carbondale. Students were randomly assigned to either a control or treatment group and given two pretests. The first pretest consisted of seventeen multiple choice questions concerning landscape construction techniques (Table 1). For the second pretest (graphic response test), students were given a list of four different landscape features (reinforced concrete wall, bluestone patio, attached shade structure, free-laid bolder wall) and asked to draw and label the various components involved in construction, Both pretests were administered to students before they had been exposed to any classroom information concerning landscape construction techniques.