Learning style preferences may impact the success of on-line students in distance education courses. In this study, students from four on-line courses voluntarily completed a modified learning styles assessment instrument. Students attaining a course average of 90% or greater were considered to have excelled in their respective course. The results from these learners were compared to those of students with lower course averages. It was determined the students that excelled in these on-line courses were visual learners that preferred more images and diagrams than textual references and instructions. This was confirmed by their choice of a map rather than written instructions to a new location when compared to their peers. In addition, they were more likely to prefer a class where they used visual skills rather than auditory skills than their peers. The high-performing students were also more likely to lose points on a timed test due to not reading the written information carefully, while their peers with lower course averages were more likely to run out of time on the test. Recognizing these learning style differences may allow faculty to design courses that better suit their on-line students.
An on-line MS nonthesis horticulture program has recently been developed by Texas Tech University. The profile of the average student participating in the program does not match the current national demographics of a 25 to 27 year old female. Rather, this distance student profile is 40- to 50-year-old male who owns his own horticultural business or serves in a horticultural management position for a city. These distance students generally excel academically as they have waited for years to pursue an advanced degree. They also communicate effectively and frequently via e-mail or course platform outlets. The distance MS students complete a traditional 36-hour program, have a graduate committee of both internal and external faculty members and stand for an oral defense. Enrollment has increased an average of 50% each semester the program has been offered. The primary challenge incurred since the inception of the program has been sustained rapid growth. While the MS nonthesis program has grown, the BS enrollment has increased almost as rapidly.
Carol Moorhead and Cynthia McKenney
The geographically uniform Texas Panhandle is dotted with shallow, ephemeral water bodies (playas), that quickly expand and contract in size. Numerous playas have been incorporated into the storm and surface-water management plan for the City of Lubbock, Texas; these playas often are surrounded by public parks. In the past, trees were planted around playas without regard to their flood tolerance. For these reasons, the objectives of this study were to catalogue trees around city playas and to determine which of these tree species survived inundation. The trees in the flood zones of eight city parks were catalogued by species in 1995, immediately after a 5-inch rain event. The water levels in all parks were monitored for the subsequent 4-month period to determine inundation time for each tree. The health of these trees was visually assessed annually. Bald cypress, mulberry, American elm, and sycamore improved in health, while the other tree species declined. Surprisingly, weeping willow and corkscrew willow, along with cedar elm, suffered the greatest decline in health.
Cynthia B. McKenney
Writing Across the Curriculum (WAC) programs are viewed as a plausible solution to poor student communication skills. These programs are further justified on the premise that writing fosters and reinforces learning in any discipline.
WAC programs integrate easily into horticulture. Traditional writing opportunities frequently utilized in horticulture include essays, papers, presentation critiques, lab reports, field trip summaries, business proposals, and cropping schedules. New opportunities might include microthemes and target audience writings.
WAC programs have their own share of pitfalls: increased grading time, reduced course content, ill-equipped faculty to teach language arts, and unrecognized objectives. Ultimately, the success or failure of a WAC program hinges on the commitment of faculty in the discipline who should have the best understanding of the language and style needed to communicate effectively in their field.
Cynthia McKenney and Robert Terry Jr.
Workshops are one of the primary tools utilized to convey information to audiences with diverse backgrounds. Frequently, the results obtained are of mixed success or unmeasurable. In this project, the Environmental Protection Agency sponsored the development of a model workshop to promote the concept of water conservation through xeriscaping. Two workshops were conducted in Spring 1994. Slide presentations, audience discussion sessions, tours of an existing xeriscape, and the administration of pre- and post-workshop surveys were included in the model. Statistical analysis comparing the surveys determined the effectiveness of the model. The results indicated both the perception and the general knowledge about water conservation were significantly improved. Promotion by newspaper was the most-effective method of reaching the audience, while TV spots were the least effective method used. The model was successful in reaching a new audience which was characterized as being 45 years old, having less than 1 year of gardening experience, and possessing some college education.
Cynthia McKenney and Robert Terry Jr.
Current estimates indicate that half of the water consumed in the urban environment is used to maintain landscapes. With this volume of water expended each year in landscape care, competition for the limited water exists. Xeriscaping reduces water demands while retaining an attractive landscape; however, the image of xeriscaping is frequently poor. In this project, workshops were conducted to measure audience perception, attitude, and knowledge of xeriscaping as a result of this type of activity. The effectiveness of the workshops was determined using pre- and postworkshop surveys. The audience's perception and attitude” toward xeriscaping improved in every area. The audience's general knowledge about the principles of xeriscaping increased significantly for almost every concept. Promotional aspects of attracting a large and diverse audience was the area needing further enhancement.
Cynthia B. McKenney and Marihelen Kamp-Glass
The effectiveness of antitranspirant type and concentration on the leaf water relations of Saliva splendens F. `Firebird and Petunia × hybrida Juss. `Comanche'. Two film-forming antitranspirants, Cloud Cover and Folicote, were tested at three different concentrations in two different environments. The leaf water potential, stomatal conductance, and relative water content were evaluated. Transpiration per unit vapor pressure deficit and stomatal conductance for both crops decrease slightly but there was no trend with respect to the film type, environment or concentration rate. The leaf water potentials and relative water content did not show significant difference after antitranspirant application. In order for antitranspirant application to be of benefit to the growth of herbaceous plants, a more durable coating that remains semipermeable would have to be utilized.
Genhua Niu, Denise S. Rodriguez and Cynthia McKenney
Wildflowers are good candidates for water-wise landscapes because many of them are drought-tolerant after establishment. Little information is available regarding whether these herbaceous wildflowers are tolerant to salt stress. Container experiments were carried out in a greenhouse and a shadehouse under semiarid climate conditions to investigate the salt tolerance of six native wildflowers: Salvia farinacea (mealy cup sage), Berlandiera lyrata (chocolate daisy), Ratibida columnaris (Mexican hat), Oenothera elata (Hooker’s evening primrose), Zinnia grandiflora (plains zinnia), and Monarda citriodora (lemon horsemint). In the greenhouse experiment, mealy cup sage, Hooker’s evening primrose, and plains zinnia were irrigated with a saline solution with an electrical conductivity (EC) of 1.5 (control, nutrient solution), 2.8, 4.1, 5.1, or 7.3 dS·m−1 for 45 days. All plants survived except for plains zinnia at EC of 7.3 dS·m−1. Shoot dry weights decreased as EC of irrigation water increased for all three species. In the shadehouse experiment (second year), plants of all species (plains zinnia was not included) were irrigated with saline solutions at EC of 0.8 (control, tap water), 2.8, 3.9, 5.5, or 7.3 dS·m−1 for 35 days. Plants were fertilized with slow-release fertilizer in the shadehouse experiment. After 5 weeks of treatment, all plants of lemon horsemint in the elevated salinity treatments, regardless of EC levels, were dead. The visual foliar salt damage rating was lowest for lemon horsemint. Chocolate daisy had low survival percentages and low foliar ratings at EC of 5.5 dS·m−1 and 7.3 dS·m−1. For the other three species, survival percentages were 80% and 90% at EC of 7.3 dS·m−1. Hooker’s evening primrose and mealy cup sage had similar low foliar visual ratings at EC of 7.3 dS·m−1, whereas Mexican hat plants had high foliar visual ratings regardless of salinity treatment. All species had similar high uptake of Na+ in shoots, whereas Hooker’s evening primrose had slightly higher Cl− concentrations compared with other species. Based on these results, lemon horsemint was most sensitive to salinity stress followed by chocolate daisy. Hooker’s evening primrose and mealy cup sage were moderately tolerant and may be irrigated with low salinity water at EC of less than 3.9 dS·m−1. Mexican hat was the most tolerant among the six species.
Peter A. Dotray and Cynthia B. McKenney
Experiments were conducted to evaluate established and seeded buffalograss [Buchloe dactyloides (Nutt.) Engelm.] tolerance to herbicides applied preemergence at labeled use rates. Established buffalograss tolerated benefin, benefin plus oryzalin, benefin plus trifluralin, DCPA, dithiopyr, isoxaben, oryzalin, pendimethalin, and prodiamine. For established buffalograss treated with atrazine, diuron, or metolachlor, the injury rating was 27% to 71% at 6 weeks after treatment (WAT) and 22% to 84% at 15 WAT. Buffalograss tolerated cyanazine, metsulfuron, propazine, and pyrithiobac applied in the seedbed. Seeded buffalograss stands were reduced by alachlor, atrazine, dicamba, linuron, metolachlor, metribuzin, oryzalin, pendimethalin, and quinclorac. Stand reductions by dicamba (a preplant and postemergence herbicide), up to 100% at 4 WAT and up to 85% at 16 WAT, were those most severe. Seeded and established buffalograss showed excellent tolerance to a few preemergence herbicides that could be used effectively and safely to control weeds during establishment and maintenance of buffalograss. Chemical names used: 2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide (alachlor); 6-chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine (atrazine); N-butyl-N-ethyl-2,6-dinitro-4-(trifluoromethyl)benzenamine (benefin); 2-[[4-chloro-6-(ethylamino)-1,3,5-triazin-2-yl]amino]-2-methylpropanenitrile (cyanazine); dimethyl 2,3,5,6-tetrachloro-1,4-benzenedicarboxylate (DCPA); 3,6-dichloro-2-methoxybenzoic acid (dicamba); S,S-dimethyl 2-(difluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-3,5-pyridinedicarbothioate (dithiopyr); N′-(3,4-dichlorophenyl)-N,N-dimethylurea (diuron); N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxybenzamide (isoxaben); N′-(3,4-dichlorophenyl)-N-methoxy-N-methylurea (linuron); 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide (metolachlor); 4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one (metribuzin); 2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino]sulfonyl]benzoic acid (metsulfuron); 4-(dipropylamino)-3,5-dinitrobenzenesulfonamide (oryzalin); N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine (pendimethalin); N 3,N 3-di-n-propyl-2,4-dinitro-6-(trifluoromethyl)-m-phenylenediamine (prodiamine); 6-chloro-N,N′-bis(1-methylethyl)-1,3,5-triazine-2,4-diamine (propazine); 2-chloro-6-[(4,6-dimethoxy-2-pyrimidinyl) thio]benzoic acid (pyrithiobac); 3,7-dichloro-8-quinolinecarboxylic acid (quinclorac); Team™ [premix of 1.33% benefin and 0.67% 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine] (trifluralin).
Samuel C. Hill* and Cynthia B. McKenney
Given the regularity of periods of drought in the southwestern U.S., concern over an ample supply of high quality water is always an issue. With a diminishing water supply, higher quality water will likely be diverted to higher priority uses; therefore, concern arises over the availability and quality of water for landscape use. This project was designed to screen representative cultivars from several of the major garden rose categories (China, Tea, Polyantha, Hybrid Tea, and Found Roses) for tolerance to saline irrigation water. Roses were placed in a completely randomized design with four replications in a container holding area. Salinity treatments were designed to be a 2:1 molar ratio of NaCl:CaCl2. The treatments consisted of 0, 6.25, 12.5, 25, and 50 mmol NaCl. The volume of solution applied to each treatment was adjusted at every irrigation event to meet ET and produce a 30% leaching-fraction. At the conclusion of the study, the China rose retained the best foliage while one of the hybrid tea roses maintained flowering throughout the study at all treatment levels. It appears that the roses with the smallest leaflets were able to tolerate salinity better than those with larger leaflets. Results of the tissue sample, leachate, spad and media analyses will also be presented.