Search Results

You are looking at 1 - 10 of 16 items for

  • Author or Editor: William E. Klingeman x
Clear All Modify Search
Free access

William E. Klingeman*, Darren K. Robinson and Gary L. McDaniel

Mugwort, or false chrysanthemum (Artemisia vulgaris L) is a well-adapted invasive plant that presents increasing management challenges to agricultural producers, Green Industry professionals and homeowners across portions of the eastern U.S. The ability of mugwort to regenerate from cut rhizome sections has not been adequately quantified for substrates that are typical of landscapes and nursery fields, container nurseries, and propagation beds. Cut rhizome sections were analyzed by rhizome color, length, and the presence or absence of a leaf scale. Media substrates included pine bark, sand, and soil. Rhizomes darken with time and color did not account for differences in growth among treatments. When grown in pine bark, sand, and soil substrates during 45-d trials, 85%, 78%, and 69% of 2 cm-long rhizome sections produced both roots and shoots. These results contrast with previous research. When rhizome fragments 0.5 cm long did not include a leaf scale, slightly fewer than 31% produced both roots and shoots in soil. Fewer rhizomes survived in soil, but root and shoot fresh masses of soil-grown rhizomes were greater than rhizomes that were regenerated in pine bark and sand. When rhizome sections had a leaf scale, survival, fresh masses of roots and shoots, shoot height, leaf number and root lengths were greater, regardless of substrate type. Root initials emerged in the internode between leaf scales and also adjacent to leaf scales. Shoot emergence preceded root emergence from rhizome sections. Growers, landscape managers and homeowners should scout regularly and initiate aggressive controls when mugwort populations are found.

Free access

William E. Klingeman, Gretchen V. Pettis and S. Kristine Braman

Although lawn care and landscape maintenance professionals appear increasingly willing to use Integrated Pest Management (IPM) strategies and adopt nonchemical pest management alternatives into management practices, the opinions of landscape management professionals have not been assessed regarding anticipated influences of increased use of insect- and disease-resistant ornamental plants on grounds management activities, client satisfaction, or business profitability. Lawn care and landscape professionals are well positioned to implement many IPM practices into landscape use and to educate their consumer clients about ecologically sustainable landscape designs and beneficial management techniques. Conversely, if some of these professionals are unwilling to advocate installation of ornamental host plants that are resistant to certain pests or diseases, market success of such plants can be limited. To better understand perceptions of green industry professionals related to these issues, we surveyed lawn care and landscape business owners and employees to categorize their perceptions about insect- or disease-resistant ornamental plants and qualified their beliefs in relation to both personal and firm demographics. A total of 391 completed surveys were received from Tennessee, Florida, and Georgia participants. Data analyses revealed that lawn care and landscape maintenance professionals largely believe that insect- and disease-resistant plants will benefit their businesses and should result in increased client satisfaction. Only ≈4% of respondents stated concern that business would incur at least some negative effect if pest-resistant plants were made more available or used in greater numbers in client landscapes. Among all respondents, there was an average expectation that 60% or more of plants within a given client's landscape would have to be resistant to insect pests or plant diseases to result in a decrease in company profits. If insect- and disease-resistant ornamental plants were used more widely in client landscapes, respondents expected that the required number of site visits to client landscapes would remain unchanged and that moderate reductions in insecticide and fungicide use would result.

Free access

Andrew Jeffers, Marco Palma, William E. Klingeman, Charles Hall, David Buckley and Dean Kopsell

Production of high-quality nursery liners has long been a foundation principle for enabling success and business longevity in the competitive nursery industry. Unfortunately, many different characteristics can be used to define liner “quality,” ranging from physiological parameters measurable in scientific studies field establishment success and transplant production performance to gut-level hunches on the part of growers. A more complete understanding of what buyers are looking for in a bare-root liner would significantly enhance the success of producers in meeting the demands of end-users. As a result, a choice study involving a point-of-purchase simulation was designed to assess preferences of green industry professionals when viewing bare-root 1 + 0 nursery liners. A conjoint design was used for this study and involved six key attributes of liners: 1) number of first-order lateral roots (FOLR); 2) price; 3) production region; and uniformities of 4) height; 5) canopy density; and 6) liner caliper. A visual survey based on a large, color graphic depicting six distinct bare-root 1 + 0 liners with different combinations of attributes was administered together with a demographic questionnaire at four different green industry tradeshows and extension grower education and outreach venues in the southeastern United States. Results from 248 completed surveys corroborated previously reported results suggesting that high FOLR is the most important attribute influencing preference for 1 + 0 liner products followed by uniform liner height and canopy density. Contrary to a priori expectations, neither price nor region of production substantially influenced product preference. Utility values were calculated for each attribute level using outputs from the experimental model. These values can be used by growers to adjust production methods to improve liners with attributes that end-users value most. In addition, growers will be able to better estimate product ratings, redirect marketing efforts, and assess sales potential for various bare-root 1 + 0 liner products in U.S. markets.

Free access

Denita Hadziabdic, Robert N. Trigiano, Stephen Garton, Mark T. Windham and William E. Klingeman

Axillary buds from a single Cladrastis kentukea tree were initially cultured on two media, woody plant medium (WPM) and Murashige and Skoog (MS) containing 0, 1, 2, or 4 μm 6–benzylaminopurine (BA). Cultures were transferred to fresh media every 4 weeks. Elongated shoots were harvested after 39 weeks and transferred to half-strength MS medium supplemented with the following concentrations of IBA: 0, 3, 30, 100, and 300 μm for 3 d, then returned to half-strength MS without growth regulators. Explants exposed to 300 μm of IBA produced significantly more roots (75%) compared to explants exposed to other treatments. Fifty-four and 45% of the microshoots rooted when exposed to 100 and 30 μm IBA, respectively. Only 4% of the microshoots rooted when exposed to 3 μm IBA and none of the control microshoots rooted. Although the 300 μm treatment yielded the most rooted plantlets, there was significantly higher terminal meristem abortion compared to other treatments. There were no statistical differences between the numbers of roots and total root length among all treatments. Additionally, all microshoots that rooted had lenticels, suggesting that presence of lenticel cambial activity can possibly improve rooting abilities of selected microshoots. Rooted microshoots were gradually acclimatized to nonsterile environment.

Free access

Gary L. McDaniel, William E. Klingeman, Willard T. Witte and Phillip C. Flanagan

One-half (18 g·ha-1 a.i.) and three-fourths (27 g·ha-1 a.i.) rates of halosulfuron (Manage®, MON 12051) were combined with adjuvants and evaluated for effectiveness in controlling purple nutsedge (Cyperus rotundus L.) and for phytotoxic responses exhibited by two kinds of container-grown ornamental plants. Adjuvants included X-77®, Scoil®, Sun-It II®, Action “99”®, and Agri-Dex®. By 8 weeks after treatment (WAT), halosulfuron combined with X-77®, Agri-Dex®, or Action “99”® at the lower halosulfuron rate provided <90% purple nutsedge suppression. In contrast, Sun-It II® provided 100% control when combined with the higher halosulfuron rate. Nutsedge control persisted into the following growing season and halosulfuron combined with either Scoil® or Sun-It II® provided >97% suppression of nutsedge tuber production. Growth of liriope [Liriope muscari (Decne.) Bailey `Big Blue'] was not inhibited by Scoil® or Sun-It II® adjuvants in combination with the low rate of halosulfuron. However, regardless of the rate of halosulfuron or adjuvant used, initial foliar chlorosis was observed in both daylily (Hemerocallis sp. L. `Stella d'Oro') and liriope. All liriope receiving halosulfuron with X-77®, Scoil®, or Sun-It II® adjuvants recovered normal foliage by 8 WAT. By contrast, at 8 WAT some daylily still maintained a degree of foliar discoloration. In addition to chlorosis, all treatments reduced flower number in daylilies. The number of flower scapes produced by liriope was not affected by halosulfuron when in combination with either Sun-It II® or Scoil®. The high rate of halosulfuron combined with X-77® or Action “99”® improved control of purple nutsedge. However, this rate inhibited growth of both species, daylily flower numbers, and scape numbers of liriope, regardless of adjuvant. Chemical names used: halosulfuron (Manage®, MON 12051, methyl 5-{[(4,6-dimethyl-2-pyrimidinyl) amino] carbonyl-aminosulfonyl}-3-chloro-1-methyl-1-H-pyrozole-4-carboxylate); proprietary blends of 100% methylated seed oil (Scoil® and Sun-It II®); proprietary blend of 99% polyalkyleneoxide modified heptamethyl trisiloxane and nonionic surfactants (Action “99”®); alkylarylpolyoxyethylene, alkylpolyoxyethelene, fatty acids, glycols, dimethylpolysiloxane, and isopropanol (X-77®); proprietary blend of 83% paraffin-based petroleum oil, with 17% polyoxyethylate polyol fatty acid ester and polyol fatty ester as nonionic surfactants (Agri-Dex®)

Full access

William E. Klingeman, Gregory R. Armel, Henry P. Wilson, Thomas E. Hines, Jose J. Vargas and Philip C. Flanagan

Mugwort (Artemisia vulgaris) is a perennial invasive weed species that has infiltrated row crops, turfgrass, ornamentals, and various noncrop areas. Currently, multiple mimics of indole-3-acetic acid can provide control of this species; however, these herbicides can damage certain sensitive ornamental plants. When applied at reduced rates, the p-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides mesotrione and topramezone have demonstrated some selectivity among certain ornamental plants. Field and greenhouse studies were initiated to evaluate whether these herbicides could control mugwort when applied alone, or in mixtures with photosystem II (PSII)-inhibiting herbicides that often provide synergistic weed control. In the field, mesotrione controlled mugwort between 30% and 60% by 21 days after treatment when applied at 0.093 to 0.187 lb/acre. When the PSII-inhibiting herbicide atrazine was added, control increased to 78% and 79%. In the greenhouse, similar rates produced greater control in mugwort, and all mesotrione treatments limited mugwort regrowth by at least 95% when compared with untreated control. When HPPD inhibitor rates were reduced further, the addition of the PSII inhibitors atrazine or bentazon was not sufficient at providing acceptable control of mugwort.

Full access

William E. Klingeman, David B. Eastwood, John R. Brooker, Charles R. Hall, Bridget K. Behe and Patricia R. Knight

A survey was administered to assess plant characteristics that consumers consider important when selecting landscape plants for purchase. Visitors to home and garden shows in Knoxville and Nashville, Tenn.; Detroit, Mich.; and Jackson, Miss., completed 610 questionnaires. Respondents also indicated their familiarity with integrated pest management (IPM) concepts, pest control philosophy, recognition of flowering dogwood (Cornus florida) pests and diseases, including dogwood powdery mildew (Microsphaera pulchra), and willingness-to-pay a price differential for a powdery-mildew-resistant flowering dogwood. Fewer than half of the respondents in any city indicated familiarity with IPM, although they were familiar with organic farming and pest scouting components of an IPM program. Willingness-to-pay was relatively consistent across all four locations. The uniformity of average tree premiums, which ranged from $11.87 in Jackson to $16.38 in Detroit, supports the proposition that customers are willing to pay a substantially higher price for a landscape tree that will maintain a healthier appearance without the use of chemical sprays. Factors affecting consumer demand for landscape nursery products and services can be paired with consumer awareness of IPM terminology and practices to create an effective market strategy for newly developed powdery-mildew-resistant dogwood cultivars.

Full access

James T. Brosnan, Gregory R. Armel, William E. Klingeman III, Gregory K. Breeden, Jose J. Vargas and Philip C. Flanagan

Star-of-bethlehem (Ornithogalum umbellatum) commonly invades turfgrass stands throughout the transition zone. Field experiments were conducted to evaluate sulfentrazone and mixtures of mesotrione and topramezone with bromoxynil and bentazon for selective star-of-bethlehem control in cool-season turf. At 4 weeks after treatment (WAT), applications of sulfentrazone at 0.25 and 0.38 lb/acre provided >95% control of star-of-bethlehem in 2008 and 2009. Star-of-bethlehem control following applications of commercial prepackaged mixtures containing sulfentrazone was not significantly different from applications of sulfentrazone alone, at either rate, at 4 WAT in 2008 and 2009. Control with carfentrazone-ethyl at 0.03 lb/acre measured to <75% at 4 WAT each year. Star-of-bethlehem control at 2, 3, and 4 WAT with topramezone at 0.033 lb/acre was increased by 77%, 50%, and 46%, respectively, from the addition of bromoxynil at 0.50 lb/acre. Similarly, the inclusion of bromoxynil at 0.50 lb/acre increased the level of control observed following treatment with mesotrione at 0.28 lb/acre by 77%, 30%, and 32% at 2, 3, and 4 WAT. These data suggest that sulfentrazone and mixtures of topramezone and mesotrione with bromoxynil can be used to provide postemergence control of star-of-bethlehem in cool-season turf.

Full access

Rebecca M. Koepke-Hill, Gregory R. Armel, William E. Klingeman, Mark A. Halcomb, Jose J. Vargas and Phillip C. Flanagan

Field and greenhouse studies were conducted to determine if two indole-3-acetic acid herbicide mimics, aminopyralid and aminocyclopyrachlor-methyl, applied at 70, 140, and 280 g·ha−1 postemergence (POST) would control mugwort (Artemisia vulgaris) in an abandoned nursery. These were compared with the commercial standards picloram at 280 g·ha−1 a.i. and clopyralid at 280 g·ha−1. In the field study, picloram and clopyralid controlled mugwort 75% and 31% by 365 days after treatment (DAT), respectively. In contrast, aminopyralid and aminocyclopyrachlor-methyl applied at 140 g·ha−1 controlled mugwort over 90% by 365 DAT. In the greenhouse study, aminopyralid and aminocyclopyrachlor-methyl applied at 140 g·ha−1 controlled mugwort 92% and 96% respectively, although aminopyralid at 70 g·ha−1 provided better visual control (94%) in comparison with aminocyclopyrachlor-methyl (79%) at 70 g·ha−1. Regardless, following shoot growth removal at 30 DAT, mugwort failed to regrow by 60 DAT following exposures to all rates of both herbicides. On the basis of these studies, aminopyralid and aminocyclopyrachlor-methyl have potential to provide excellent control of mugwort compared with the current standards clopyralid and picloram.

Full access

Andrew H. Jeffers, William E. Klingeman, Charles R. Hall, Marco A. Palma, David S. Buckley and Dean A. Kopsell

Ornamental plant growers must be able to accurately assess production costs associated with woody liner stock to gain profit potential in a highly competitive industry. Fixed and variable cost inputs may not be intuitive or readily apparent to growers and may even differ between common types of production in the trade. To help liner producers identify profit-based price points for their woody ornamental liner stock, we modeled costs associated with producing familiar species and cultivars of a representative deciduous shade tree, a broadleaf evergreen, and a needle leaf evergreen liner. Production costs are projected down to individual plant units for each of the three most common liner production systems, including a field ground bed system, a polyhouse-covered (plant protection structure sheathed with one layer of 6-mil polyethylene film) ground bed system, and a polyhouse-covered container system. Production costs for individual plants varied due to the actual growing space available within each system. The field ground bed system offered greatest flexibility in crop planting density, with cost potentially distributed among the largest number of salable units. In addition to modeled costs, advantages and disadvantages of each liner cropping system are discussed.