bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tolerance of Ornamental Grasses to Preemergence Herbicides
Authors: Derr Jeffrey F. 
Published: August 2020

Abstract
Tolerance of ornamental grasses to preemergence herbicides commonly-used in nursery crop production and turfgrass maintenance was evaluated in container studies. Gallery controlled the broadleaf weeds tested but did not control large crabgrass. Surflan at 2.2 kg ai/ha (2.0 lb ai/A) controlled all weeds except rice flatsedge. Pennant at 2.2 kg ai/ha (2.0 lb ai/A) controlled rice flatsedge but not eclipta. Pendulum, Ronstar, Barricade and OH2 also did not control eclipta at the lower use rate. Although growth suppression and stand reduction was observed in certain herbicide/ornamental grass combinations, the species tested generally exhibited good tolerance to the chemicals tested. Ornamental grass tolerance improved by the second herbicide application. After two applications, no rate of Surflan, Pendulum, or Barricade caused a significant reduction in growth of any of the five ornamental grass species tested.
Methods to Evaluate Host Tree Suitability to the Asian Longhorned Beetle, Anoplophora glabripennis
Authors: Ludwig Scott W. , Lazarus Laura , McCullough Deborah G. , Hoover Kelli , Montero Silvia , Sellmer James C. 
Published: August 2020

Abstract
Two procedures were evaluated for assessing tree susceptibility to Anoplophora glabripennis. In the first procedure, adult beetles were caged with a section of sugar maple, northern red oak, white oak, honeylocust, eastern cottonwood, sycamore or tulip poplar wood. Results showed that females laid viable eggs on sugar maple, red oak, white oak and honeylocust. Oviposition did not occur on cottonwood, sycamore, or tulip poplar. Eighty-seven percent of the first instar larvae survived in white oak, followed by sugar maple (82%), honeylocust (50%), and red oak (39%). In the second procedure, first instar larvae were manually inserted into potted sugar maple, green ash, and red oak trees and allowed to feed for 60 or 90 days. Significantly more larvae survived for 90 days within the red oak (67%) compared to green ash (17%). Larvae recovered from red oak weighed significantly more than larvae from sugar maple or green ash. Larval survival was positively related to height of insertion. These results indicate: 1) controlled laboratory and greenhouse-based procedures can be used to assess tree suitability to A. glabripennis and 2) A. glabripennis will oviposit and larvae can develop in northern red oak for up to 90 days, suggesting that this species may be a potential host.
Suitability of Various Species of Viburnum as Hosts for Pyrrhalta viburni, an Introduced Leaf Beetle
Authors: Weston Paul A. , Desurmont Gaylord 
Published: August 2020

Abstract
Viburnum leaf beetle [(Pyrrhalta viburni (Paykull)], a newly introduced pest of viburnums in the United States, feeds selectively on plants in the genus Viburnum. We measured in the laboratory the ability of larvae of viburnum leaf beetle to complete development and propensity of adults to feed on a number of species of Viburnum ranging in susceptibility from completely susceptible to quite resistant as determined by earlier field observations. As expected, larvae completed development on viburnums rated as ‘susceptible,’ but were largely unable to do so on those rated as ‘moderately’ or ‘highly’ resistant. The pattern of host acceptance by adults was less consistent, with some adults feeding considerably on species not found to be susceptible in the field. Several accessions were not fed on at all by adults, indicating the presence of deterrent or toxic factors. Our results suggest that the species previously identified as resistant in the field are unsuitable hosts for viburnum leaf beetle, and will not likely be devastated by the pest even if all susceptible hosts are eliminated from an area.
Evaluation of Experimental Extended-Delivery Granular Preemergent Herbicide Formulations for Direct Application to Nursery Containers
Authors: Fain Glenn B. , Gilliam Charles H. , Wehtje Glenn R. , Grey Timothy L. , Osborne Jason A. , Tilt Ken M. 
Published: August 2020

Abstract
Studies evaluated the efficacy of experimental extended-delivery herbicide formulations for direct application to containers. The purpose for direct application to containers is to reduce non-target loss from the current practice of broadcast applications. A separate laboratory study was also conducted to evaluate the rate response of oryzalin on germination of large crabgrass (Digitaria sanguinalis L.). Results of the laboratory study indicate that crabgrass germination is reduced when seeds are exposed to the preemergence herbicide oryzalin at concentrations of ≥0.025 parts per million. Experimental herbicides were produced by formulating polymeric exchange resins and cellulose complex carriers with oryzalin. Experimental herbicides reduced weed shoot dry weight at 120 DAT and 150 DAT when compared to Rout®, Surflan® and the untreated control.
Propagation of Catnip by Terminal and Single-node Cuttings
Authors: St. Hilaire Rolston 
Published: August 2020

Abstract
Adventitious rooting and subsequent development of rooted cuttings were evaluated for terminal, single-node, and tip cuttings of catnip (Nepeta cataria L.). During an eight-week production period, cuttings were treated with indole-3-butyric acid (IBA) at 0, 1, 3, and 8 g/kg (0, 1000, 3000, and 8,000 ppm), rooted for one to four weeks, and then grown in the greenhouse for four to seven weeks. At harvest, a first experiment showed that terminal cuttings propagated for four weeks accumulated less shoot dry weight (24 g) than cuttings propagated for two (36 g) or three (31 g) weeks. Terminal cuttings treated with 3 g/kg of IBA and propagated for four weeks had the highest root dry weight, which averaged 12.1 g. In the second experiment, length of the longest shoot and primary root and the number of roots and shoots were greater in single-node cuttings propagated for two or three weeks than those propagated for one week. A third experiment revealed that the development of primary roots in single-node and tip cuttings was similar during a 15-day rooting period.
Screening Commercial Peat and Peat-based Products for the Presence of Ericoid Mycorrhizae
Authors: Gorman Nicole R. , Starrett Mark C. 
Published: August 2020

Abstract
Pieris floribunda (Pursh) Benth. & Hook., a known host of ericoid fungi, was used as a model plant to investigate the presence of ericoid mycorrhizal fungi in select peat and peat-based products. After growing in each medium for 75 days, roots of seedlings were examined and average percent colonization was determined for each sample. Results indicate that these fungi are present in the majority of peat and peat-based media tested. Seedlings grown in some of the selected media had a greater percentage of root cells colonized by ericoid mycorrhizae than others in the study.
Molecular Assessment of Remontant (Reblooming) Hydrangea macrophylla Cultivars
Authors: Lindstrom Jon T. , Pelto Matthew C. , Dirr Michael A. 
Published: August 2020

Abstract
Randomly amplified polymorphic DNA (RAPD) markers were used to distinguish five remontant and two cold-hardy Hydrangea macrophylla (Thunb.) Ser. taxa. Eleven primers generated sufficient polymorphisms to separate these seven cultivars into two groups. One group contained ‘Penny Mac’, ‘Dooley’ and ‘Nikko Blue’, while the remaining taxa, ‘David Ramsay’, ‘Endless Summer’, ‘Decatur Blue’ and ‘Oak Hill’ were clustered in the second group. All hydrangea cultivars examined are closely related; the most divergent cultivars exhibited 88% similarity based on RAPD markers.
Effects of Auxin Concentration and Medium Temperature on Four Woody Plant Taxa Propagated by Stem Cuttings using Recirculating Subirrigation in a Growth Chamber
Authors: Owen James S. , Johnson William A. , Maynard Brian K. 
Published: August 2020

Abstract
Four woody plant taxa (‘Sparkleberry’ holly, ‘Mariesii’ viburnum, ‘Shasta’ viburnum, and Red Sunset® maple) were propagated from softwood stem cuttings in a recirculating subirrigation propagation system to evaluate the effect on adventitious root formation of three auxin (Dip-n-Grow®) concentrations [0 (water), 20: 1, or 10: 1] and three medium temperatures [20C (68F), 23C (74F), or 26C (79F)]. All taxa showed a positive rooting response to auxin treatment. Compared to cuttings treated with water, root number of all taxa doubled when treated with the highest auxin concentration (10: 1 Dip-n-Grow® dilution). Length of the longest root of rooted cuttings increased with auxin treatment of two taxa. Medium temperature also affected rooting of all taxa. The intermediate temperature evaluated, 23C (74F), was optimal for all rooting parameters on cuttings of ‘Mariesii’ viburnum, and for root length and percentage rooting on cuttings of ‘Shasta’ viburnum and Red Sunset® maple. A propagation medium temperature of 26C (79F) resulted in the greatest root number on cuttings of ‘Shasta’ viburnum, while 20C (68F) was optimal for root number on cuttings of Red Sunset® maple. Root numbers on cuttings of ‘Mariesii’ viburnum were reduced at 20C (68F) and 26C (79F), which appeared to be sub-and supra-optimal temperatures, respectively, for root initiation. All rooting parameters on cuttings of ‘Sparkleberry’ holly increased with propagation medium temperature. Temperature-auxin interactions were apparent for root number and length on cuttings of ‘Mariesii’ and ‘Shasta’ viburnum. The recirculating subirrigation system was useful for evaluating the basal temperature and auxin dose interactions and was effective for rooting softwood stem cuttings without intermittent mist irrigation.
Multiple Benzyladenine Applications Increase Shoot Formation in Nandina
Authors: Keever Gary J. , Morrison Teresa A. 
Published: August 2020

Abstract
A study conducted from 2000 to 2002 determined the effects of multiple applications of benzyladenine (BA) applied at different concentrations on shoot formation, whole plant size, and phytotoxicity in Nandina domestica Thunb. In 2000, shoot counts increased in ‘Harbour Dwarf’ by up to 107% and 480% as the number of weekly BA applications at 2500 and 5000 ppm, respectively, increased to five. Likewise, the number of shoots per plant increased as BA rate increased. In response to five weekly foliar BA applications in 2001 and 2002, the number of new shoots on ‘Harbour Dwarf’ increased linearly 10-fold over the control as BA rate increased to 5000 ppm in 1250 ppm increments. In 2002, shoot formation increased linearly by up to six additional shoots per plant with increasing BA rate in ‘Harbour Dwarf’ and quadratically by up to two additional shoots per plant in ‘Firepower’ by 90 days after initial treatment (DAT) with five applications of up to 5000 ppm BA. Shoot formation in the tall, upright cultivars ‘Royal Princess’ and ‘Moyer's Red’ also increased linearly with increasing BA rate, by two and &lt;1 shoot per plant, respectively, in 2002 only. Five foliar applications of 2500, 3750, and 5000 ppm BA injured upper, immature foliage, but did not adversely affect plant appearance by 90 DAT. Treatment effects on plant size were minimal.
Response of Lagerstroemia x ‘Tuscarora’ to Multiple Applications of Pistill
Authors: Morrison Teresa A. , Keever Gary J. , Gilliam Charles H. 
Published: August 2020

Abstract
Profuse flowering, followed by heavy fruit set and cessation of vegetative growth, extends the production cycle of many crapemyrtle cultivars, particularly ‘Tuscarora’. A study was conducted in 2002 to determine the effect of multiple applications of 1000 ppm Pistill (ethephon) on flower abortion and subsequent axillary shoot growth in Lagerstroemia indica xfauriei ‘Tuscarora’ when applied to open flowers in July and August before fruit set. In one experiment, Pistill was applied 0, 1, 2, 3, 4, or 5 times during the two flowering periods, and at 7-, 14-, and 21-day intervals (DI) during each period in a second experiment. In the first experiment, two applications made during the July flush led to 48% flower abortion, whereas by the fifth application, made during the August flush, the abortion rate had increased to 58%. Axillary shoot formation occurred predominantly following the July flush, with 34 and 60 new shoots developing on plants receiving one and two applications, respectively. Pistill applications every 7, 14, or 21 days to open flowers during the first floral flush prompted flower abortion of 81, 51, and 18%, respectively, compared to no abortion in untreated trees. The same Pistill treatments applied during the August flush resulted in 96, 96, 54, and 0% abortion, respectively. Trees receiving Pistill at 7 DI, 14 DI, and 21 DI, respectively, formed 96, 108, and two new shoots following the July flower flush and 13, 27, and two new shoots following the August flush.
Technical Information Requested by Hispanic Nursery Employees – Survey Results from Oregon and Ohio
Authors: Mathers H.M. 
Published: August 2020

Abstract
The demographics of the nursery industry in the United States have changed dramatically in the past 10–15 years. Today, the majority of the worker level of nursery staff is Spanish-speaking. Approximately 90% of the Oregon and 60% of the Ohio nursery industry work forces are composed of Hispanic employees. Many of these employees understand little English, and Spanish is their primary language. In Oregon and Ohio 375 and 250 surveys, respectively, were distributed to Spanish-speaking nursery employees. One-hundred-ninety-three surveys were completed in Oregon, as compared to 127 in Ohio. The purpose of these surveys was to determine the backgrounds, experience level and work activities of Hispanic nursery employees, their technical information interests, and what resources were available to these employees. The survey responses came from 3 sources: Interviews at training programs, on-farm visits and mailed surveys in a newsletter format. The three sources were pooled and analyzed. The survey targeted nursery workers filling primarily manual labor positions; however, we found this staff level was predominantly Hispanic. Also, the majority of those surveyed were Hispanic employees who had risen to supervisor or crew leader level, such as propagation area supervisors. Plant identification (95%) and weed control (90%) were the foremost technical topics of interest of Ohio surveyed employees. This was significantly different from the survey results in Oregon where 81% chose insect control, 77% weed control, and 66% disease control as leading topics of interest. In Oregon, plant identification rated only 45%. Ninety-three percent of Ohio and 97% of Oregon newsletter readers wanted to receive future issues of the Spanish language newsletter. This finding was consistent with responses from nursery visits and training programs in the two states where respondents indicated their positive reception to receiving technical information in Spanish.
Effect of Commercial Arbuscular Mycorrhizal Fungi on Growth, Survivability, and Subsequent Landscape Performance of Selected Container Grown Nursery Crops
Authors: Carpio Lucila Amaya , Davies Fred T. , Arnold Michael A. 
Published: August 2020

Abstract
This research evaluated the effects of commercially available arbuscular mycorrhizal fungi (AMF) on growth of selected ornamental plant species grown under a nursery-container production system. Subsequent plant survivability and growth in the landscape was also evaluated for two seasons. Acacia greggii, Chilopsis linearis, Diospyros virginiana, Platanus occidentalis, Ipomoea carnea and Plumbago auriculata were inoculated with commercial AMF: EndoNet®, MycorisePro®, or non-inoculated (NonAMF). Platanus occidentalis had a fourth mycorrhizal treatment, which included BioterraPLUS®. EndoNet® and MycorisePro® enhanced growth of C. linearis, I. carnea and P. auriculata during nursery-container production. Growth enhancement of P. occidentalis was significant with BioterraPLUS®, EndoNet® and MycorisePro® compared to NonAMF. During the container phase, greatest colonization (total arbuscules, vesicles/endospores, and intraradical hyphae) occurred with I. carnea and P. auriculata inoculated with EndoNet® and MycorisePro®. After the 1st growing season following out planting, AMF inoculated P. occidentalis and C. linearis had greater growth and AMF inoculated P. auriculata had higher survival than NonAMF plants. However, by the end of the 2nd growing season there were no differences in survival or growth among AMF treatments. The similarity in plant growth during the 2nd season was due in part to a high and active indigenous AMF population in the landscape site that colonized the NonAMF plants after transplanting.
Models for Predicting the Risk of Naturalization of NonNative Woody Plants in Iowa
Authors: Widrlechner Mark P. , Thompson Janette R. , Iles Jeffery K. , Dixon Philip M. 
Published: August 2020

Abstract
Nursery and landscape professionals have introduced many useful non-native woody plants for managed landscapes, but the potential exists for new introductions to escape from cultivation and become pests. The objective of this study was to develop a comprehensive strategy to assess the risk of naturalization of non-native woody plants in Iowa. We examined life-history traits and native distributions of 100 woody plant species, including 28 species known to naturalize in Iowa and 72 other species not known to naturalize in the state. We tested three approaches to predict naturalization of woody plants in Iowa: (1) direct application of a previously developed decision tree designed to predict naturalization on a continental scale within North America; (2) application of the continental model modified to include traits important on a regional scale, and (3) development of a new regional model that included a geographic-risk component along with life-history traits. Our modifications to the continental model and the new regional model all were more powerful than the unmodified, continental model, as measured by their ability to classify species (classification rate) based on risk of naturalization, without reducing accuracy, as measured by the frequency of misclassification (error rate). Classification rates ranged from 65% for the unmodified continental model to 90% for the modified continental model. Error rates varied from 6% for the new regional model to 20% for the unmodified continental model, including horticulturally limiting error rates of 4 to 17%, respectively.
Effect of Chilling Duration on Growth of Hosta plantaginea and 11 Related Cultivars
Authors: Warr Jennifer C. , Keever Gary J. , Raymond Kessler J. , Findley Douglas A. , Amling Jason W. 
Published: August 2020

Abstract
Hosta plantaginea and 11 selections with H. plantaginea parentage were chilled at 4C (39F) for 0, 1, 2, 3, or 4 weeks to determine the effect of chilling duration on subsequent plant growth. At 6 and 12 weeks after chilling treatment (WAT), response to chilling duration was selection dependent with three trends evident. At 6 WAT, eight of the 12 selections showed a decrease in new leaf formation with one or two weeks of chilling, but an increase in new leaf formation with additional chilling. In three of the 12 selections, new leaf formation increased linearly with increased chilling. New leaf formation of H. plantaginea ‘Grandiflora’ was not affected by chilling duration at 6 or 12 WAT. At 12 WAT, growth response of four of the 12 selections changed quadratically with increased chilling, similar to the response at 6 WAT, while leaf formation in seven of the 12 selections increased linearly with increasing chilling duration. At 18 WAT, leaf counts increased linearly in all H. plantaginea selections with increasing chilling duration, demonstrating increased vigor. All selections showed increases in new leaf formation over the 18-week period following chilling, demonstrating that chilling, though beneficial, was not required, and in the short-term, the response to chilling was selection dependent.
Propagation of Ulmus parvifolia ‘Emerald Prairie’ by Stem Cuttings
Authors: Griffin Jason J. , Schroeder Kenneth R. 
Published: August 2020

Abstract
Stem cuttings of Ulmus parvifolia Jacq. ‘Emerald Prairie’ (‘Emerald Prairie’ lacebark elm), consisting of 7.5 to 10 cm (3 to 4 in) terminal shoot portions, were collected four times throughout the year from mature stock plants and treated with the potassium (K) salt of indole-3-butyric acid (K-IBA) ranging from 0 to 20,000 ppm (2.0%). Rooting percentages were affected greatly by K-IBA treatment and stock plant growth stage. Little to no rooting was observed without K-IBA application, whereas overall rooting for treated softwood, early semi-hardwood, late semi-hardwood, and hardwood, cuttings was 92, 86, 87, and 8%, respectively. Mean root number varied by growth stage and K-IBA concentration. Higher concentrations of K-IBA increased the number of roots on rooted cuttings except for hardwood cuttings. In general, rooting percentage and mean root number were highest at the softwood stage with 15,000 or 20,000 ppm (1.5 or 2.0%) K-IBA, resulting in 97% rooting and 15 or 22 roots per rooted cutting, respectively. However, leaf abscission was high on softwood cuttings. Semi-hardwood cuttings achieved similar rooting percentages and may exhibit better survival and growth due to greater leaf retention.
White Grub (Coleoptera: Scarabaeidae) Population Density in Relation to Root Damage to Fraser Fir Seedlings in Transplant Beds
Authors: Williamson R. Chris 
Published: August 2020

Abstract
A field experiment was conducted in 2002 to evaluate the effect of five grub densities of second instar Phyllophaga anxia (LeCont) Glasgow larvae on feeding damage to roots of young seedlings of Fraser fir, Abies fraseri (Pursh) Poir., Christmas trees in a transplant bed. Larval densities were equivalent to approximately 0, 31, 62, 93, and 124 larvae per m2 (≈ 0, 3, 6, 9, and 12 larvae per ft2). Larval survival and variations in larval and seedling weight were also evaluated. Regardless of the larval density, when P. anxia grubs were present, all Fraser fir seedlings experienced significant root damage as well as subsequent plant injury (i.e., decline or mortality). Larval density as low as one grub per 0.11 m2 (≈ 3 larvae per ft2) caused heavy to severe root damage to young, two-year-old, P2-0 Fraser fir seedlings. An inverse relationship was observed between plant weight and root damage.
Effect of Pruning, Defoliation, and Promalin on New Shoot Development of Boxwood
Authors: Musselwhite Sheri , Harris Roger , Latimer Joyce , Wright Robert 
Published: August 2020

Abstract
The objective of this study was to determine if summer dormancy of the boxwood species Buxus sempervirens L. ‘Suffruticosa’, B. sempervirens ‘Vardar Valley’, and B. sinica var. insularis Nakai ‘Justin Brouwers’ could be overcome by pruning, defoliation or growth regulator applications. Promalin (benzyladenine (BA) + GA 4+7) alone and in combination with pruning increased new shoot growth; however, results were not consistent across experiments. Pruning alone (shearing or tip removal) was also inconsistent in inducing new shoot growth. Defoliation (removal of leaves from new spring growth) dramatically increased new shoot development, especially when applied ten weeks after spring budbreak instead of closer to budbreak. This response was tempored by Promalin application.