NC7 Woody Ornamental Evaluations

10-year Performance Summaries for Accessions Offered in 1993

Ampelopsis glandulosa PI 596373 (Ames 14431)

Seven out of ten sites reported maintaining this accession through the 1-year trial period; four sites reported maintaining it through the 5-year trial period; but only one site located at Orono, ME reported maintaining it throughout the 10-year trial period.  Plant loss was attributed to winter injury (Fairbanks, AK; Fort Collins, CO; and Ames, IA) with severe winter damage recorded at Absaraka, ND.  However, the Orono, ME site (USDA Plant Hardiness Zone 4b) documented no winter injury to this accession.  Average plant height was 3.0m and 3.0m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 2.5m and 8.0m after the 5-year and 10-year trial periods, respectively.  Foliage quality was rated as clean all season long by all sites.  Flowering data were not recorded by any trial site cooperator, but peak fruiting was documented during mid-September at Orono, ME.  Only the Orono, ME site recommended this accession because of its’ cold hardiness, vigor, and attractive fruit. 

To browse a table that contains individual evaluations on this accession, click here

Berberis koreana × thunbergii 'Tara' Ames 18470

Twelve out of seventeen sites reported maintaining this accession through the 1-year trial period; eight sites reported maintaining it through the 5-year trial period; and three sites located at Absaraka, ND; Carrington, ND; and Ames, IA reported maintaining it throughout the 10-year trial period.  Fairbanks, AK was the only site to report plant loss due to winter injury.  Average plant height was 1.50m and 1.97m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 1.50m and 2.63m after the 5-year and 10-year trial periods, respectively.  Foliage quality was rated as clean all season by all sites, except Newark, OH reporting slight damage due to chewing insects.  Interestingly, the USDA-ARS Cereal Disease Laboratory in St. Paul, MN listed this clone as one of many rust resistant Berberis.  Fall colors reported included brilliant reds (Absaraka, ND and Carrington, ND), reddish-oranges (Lincoln, NE; Newark, OH), and reddish-purples (Ames, IA and Durham, NH).  Flowering peaked for the majority of the trial sites during mid to late May, except flowering at Absaraka, ND and Carrington, ND occurred around the middle of June.  Flowering at all sites occurred for approximately 18 days.  All sites rated flowering as average, except Newark, OH, which rated flowering as showy.  Fruiting peaked from approximately early August through late October.  Fruiting display was rated showy by all sites, except Lincoln, NE, which rated fruit display as average.  Durham, NH mentioned that the fruit display was very attractive, and Ames, IA cautioned that seed may be dispersed by birds.  All sites except Fairbanks, AK recommended this accession.  This accession was noted as a choice landscape shrub (Absaraka, ND and Carrington, ND), with compact growth (Morris, MN; Durham, NH; and Carrington, ND), excellent uniformity (Orono, ME; Ames, IA; and Morris, MN), and commendable fall color (Lincoln, NE; Carrington, ND; and Ames, IA).  This hybrid barberry clone is sold in the nursery trade under the name Emerald CarouselTM

To browse a table that contains individual evaluations on this accession, click here

Callicarpa dichotoma PI 564827 (Ames 3498)

Seven out of thirteen sites reported maintaining this accession through the 1-year trial period; four sites reported maintaining this accession it the 5-year trial period; and two sites located at Ames, IA and Glencoe, IL reported maintaining it throughout the 10-year trial period.  Plant loss was not attributed to any specific factor by any trial site.  Average plant height was 1.30m and 1.48m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 1.13m and 1.87m after the 5-year and 10-year trial periods, respectively.  All trial sites rated foliage quality as clean all season long.  Flowering lasting for approximately 15 days occurred during mid-July in Ames, IA and early August in Glencoe, IL.  Fruit display reached its peak around late August in Ames, IA and late October in Glencoe, IL.  Flower profusion was rated as average and fruit display as showy by both sites.  The Ames site did not recommend this accession because Callicarpa dichotoma ‘Issai’ Ames 23833 was far superior.  However, the Waseca site indicated that this accession was similar in quality to Callicarpa dichotoma ‘Issai’ Ames 23833 and would still recommend it because of its attractive berries and flowers. 

To browse a table that contains individual evaluations on this accession, click here

Caragana frutex PI 564827 (Ames 13823)

Ten out of fourteen sites reported maintaining this accession through the 1-year trial period; seven sites reported maintaining it through the 5-year trial period; and three sites located at Orono, ME; Bismarck, ND; and Fairbanks, AK reported maintaining it throughout the 10-year trial period.  Plant loss was generally attributed to poor drainage (Ames, IA and Bismarck, ND).  Average plant height was 0.96m and 0.91m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 0.64m and 0.48m after the 5-year and 10-year trial periods, respectively.  Better plant growth is indicated during the 5-year report because many of the plants that survived the 5-year trial period eventually died out due to low vigor or abnormally high amounts of rainfall.  Obviously this accession is cold hardy, but requires a well-drained soil.  Flowering was only reported by three sites, with flowers persisting for approximately 12 days during the first part of May in Fort Collins, CO and Newark, OH and the middle of June at Fairbanks, AK.  Flower effectiveness was rated as average by all three sites.  The development of pea-like pods was noted in mid-August at Fairbanks, AK and in mid-June at Newark, OH.  Both sites indicated that the pods had a dull appearance.  All trial sites summarized this accession as having either poor or medium overall performance.  Only the Fairbanks, AK site recommended this accession on the basis that it survived and flowered reliably.  All other sites indicated that this accession was not adapted to wet/moist soils, slow to establish, and not vigorous.  The Bismarck, ND noted that this accession sprouted suckers approximately 2m from the original mother plant, but stated that it was not as aggressive as other Caragana speciesIn the November 15, 1990 issue of the American Nurseryman, an article written by Dr. Harrison L. Flint and Dr. Mark P. Widrlechner featured Caragana frutex as an overlooked landscape ornamental worthy of planting.  To view this article click the following link:  Field Notes:  Caragana frutex.   This accession or other Caragana frutex populations may perform well in very well-drained soils and may be useful for parking lot/roadside plantings, but additional testing is needed. 

To browse a table that contains individual evaluations on this accession, click here

Ceanothus velutinus Ames 20129

Four out of ten sites reported maintaining this accession through the 1-year trial period, and no sites reported maintaining it throughout the 5-year or 10-year trial period.  Plant loss was generally attributed to receiving poor-quality plants.  Plants were of inferior quality, arrived in poor condition, and were inherently difficult to transplant.  Due to the low quality of plants distributed and no plants surviving to age five, a performance summary for this accession will not be posted.   

Lonicera Hybrid Selection #14 ‘Honey Rose’ Ames 20062

Eight out of thirteen sites reported maintaining this accession through the 1-year trial period; five sites reported maintaining it through the 5-year trial period; and four sites located at Ames, IA; Bismarck, ND; and North Platte, NE; and Absaraka, ND reported maintaining it throughout the 10-year trial period.  Limited snow cover at Fairbanks, AK likely contributed to the lack of winter hardiness resulting in its complete loss.  Average plant height was 2.10m and 3.48m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 1.62m and 2.49m after the 5-year and 10-year trial periods, respectively.  Foliage quality was rated as average by three trial sites (North Platte, NE; Bismarck, ND; and Absaraka, ND) and rated as unsightly due to insect damage at the Ames, IA trial site.  No fall color was reported at any trial site.  The Absaraka, ND site reported that its foliage tatters and becomes very dark as the growing season progresses.  Flowering occurred during the month of May for approximately 13 days.  Flowering effectiveness was rated as showy (Absaraka, ND) and average (Ames, IA).  All trial sites reported many flowers.  Fruits were present for approximately 12 days during mid-July at Ames, IA and early August at Absaraka, ND.  All sites rated the effectiveness of fruit as showy, except Bismarck, ND, which rated fruit effectiveness as average. 

After the 10-year trial period, all trial sites except Ames, IA recommended this accession on the basis of its cold hardiness, rosy-pink flowers, bright red berries, and resistance to honeysuckle aphids (Hyadaphis tataricae (Aizenberg)).  But comments from the Ames, IA trial site cooperator indicated that the red fruits could serve as a potential dispersal mechanism via bird feeding, and that the plant had poor foliage quality and a leggy growth habit, leading to that site withholding any recommendation.  Given the widespread invasion of related Lonicera species into natural plant communities in our region, we are concerned that the potential introduction of resistance to honeysuckle aphid will make it more difficult to control the invasion and would not recommend the use of this plant. 

To browse a table that contains individual evaluations on this accession, click here

Rhus trilobata ‘Bighorn’ PI 483445

Twelve out of sixteen sites reported maintaining this accession through the 1-year trial period; five sites reported maintaining it through the 5-year trial period; and two sites located at Carrington, ND and North Platte, NE reported maintaining it throughout the 10-year trial period.  Poor vigor and weak performance (Newark, OH and Absaraka, ND), in addition to its intolerance to saturated soils (Chanhassen, MN; Ames, IA; Fort Collins, CO; and Newark, OH) contributed to plant loss.  Average plant height was 1.76m and 2.55m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 1.76m and 3.05m after the 5-year and 10-year trial periods, respectively.  Foliage quality was variable, with ratings ranging from clean (Fort Collins, CO and Morris, MN) to average (Ames, IA and North Platte, NE) to unsightly (Carrington, ND and Newark, OH).  Unsightly foliage ratings received from Carrington, ND and Newark, OH were based on defoliation from leaf diseases, chlorosis, and poor fall color.  Flowering dates were reported at Fort Collins, CO (mid-April) and Newark, OH (end of May) for approximately 14 days.  Flowering was rated as average at Fort Collins, CO and dull at Newark, OH.  Data on fruiting effect was only observed by the North Platte, NE trial site indicating a rating of average.  Four (Fort Collins, CO; Morris, MN; North Platte, NE; and Carrington, ND) out of seven sites that reported maintaining this accession through the 5-year trial period recommended this accession on the basis of having clean foliage, nice bark, and an interesting branching habit.  However, it was noted that this accession is better adapted to xeric sites.  All of the sites (Carrington, ND and North Platte, NE) that reported maintaining this accession for the 10-year trial period failed to recommend this accession due to problems with leaf disease, poor vigor, and poor adaptation for wet areas.  This accession probably would perform the best in well-drained soils in areas with low summer humidity (Colorado, Nebraska, and Kansas), more consistent with its New Mexico origin. 

To browse a table that contains individual evaluations on this accession, click here

Staphylea bumalda PI 545683

Ten out of sixteen sites reported maintaining this accession through the 1-year trial period; four sites reported maintaining it through the 5-year trial period; but only one site located at Carrington, ND reported maintaining it throughout the 10-year trial period.  Plant loss was attributed to winter injury at Fairbanks, AK; Chanhassen, MN; Absaraka, ND; Cincinnati, OH; North Platte, NE and Carrington, ND.  The Ames, IA trial site reported that poor soil drainage likely resulted in the plants’ failure to establish.  Surprisingly, the Carrington, ND site reported maintaining this accession throughout 10-year trial period, which experiences very cold climatic conditions compared to other NC7 trial sites.  Therefore, this accessions’ overall poor adaptability is not completely understood.  Average plant height was 1.05m and 0.62m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 0.95m and 0.46m after the 5-year and 10-year trial periods, respectively.  Overall plant height and spread was greater after the 5-year trial period because of plant losses attributed to unfavorable environmental conditions between the 5-year and 10-year trial periods.  This resulted in obtaining data from only one trial site for the 10-year trial period.  Foliage quality was rated as clean all season by majority of the sites.  No fall color was reported by any trial site, except for the Carrington, ND site which indicated some yellowing.  Flowering data was captured only by the Carrington, ND site with peak flowering during the end of May for approximately 12 days.  Flowering effect was rated as average.  Fruits were apparent the end of August and were persistent for approximately 65 days.  Throughout the 5 and 10-year trial periods, there were no trial sites that recommended this accession, except for Fort Collins, CO, which rated the summary of performance as average.  Failure for recommendation by a majority of the trial sites was based on this accessions’ lack of winter hardiness, limited ornamental attributes, questionable vigor, and poor adaptation. 

To browse a table that contains individual evaluations on this accession, click here

Weigela florida 'White Knight' Ames 20128

Thirteen out of seventeen sites reported maintaining this accession through the 1-year trial period; nine sites reported maintaining it through the 5-year trial period; and six sites located at North Platte, NE; Cincinnati, OH; Carrington, ND; Orono, ME; Madison, WI; and Glencoe, IL reported maintaining it throughout the 10-year trial period.  Plant loss/damage was attributed to winter injury at Orono, ME; Chanhassen, MN; Absaraka, ND; Carrington, ND; Madison, WI; and Cincinnati, OH.  In addition, plant damage occurring at Cincinnati, OH was attributed to large animal browsing.  Average plant height was 1.26m and 1.54m after the 5-year and 10-year trial periods, respectively.  Average plant spread was 1.40m and 1.30m after the 5-year and 10-year trial periods, respectively.  Foliage quality was rated as clean all season, except by Newark, OH which reported damage to chewing insects.  Little to no fall color was reported by any trial sites except Newark, OH, which reported bronze fall color.  Flowering occurred around mid-May at Cincinnati, OH, Durham, NH and Newark, OH; mid-June at Glencoe, IL and Morris, MN; and the first of July at Carrington, ND.  Five out of six trial sites rated the flowering effect as showy.  And its flowers have an attractive fragrance, which is very rare for this species.  Only the Carrington, ND site captured fruiting data, which peaked around mid-August.  The small inconspicuous fruiting capsules were persistent for approximately 75 days and were rated as dull.  Out of six trial sites, only the Cincinnati, OH and Glencoe, IL sites recommended this accession because of its manageable growth habit, flower color, and extended blooming season.  Other trial sites questioned this accessions’ winter hardiness and indicated its performance as average for Weigela cultivars. 

To browse a table that contains individual evaluations on this accession, click here

Links:

Please send questions or comments to Mark Widrlechner at nc7mw@ars-grin.gov