January, 2002
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The current team of cooperators includes Dr. Jim Robbins and Dr. Jon Lindstrom.

The three test sites are the Hope Research Center (USDA cold hardiness zone 8a), the Little Rock/Cammack property (zone 7a), and the Fayetteville Horticulture Research farm (zone 6b). As much as possible the three test sites were prepared in a similar manner. Full sun plants were grown in row-type beds 3’wide with a 7’ grass alley. Plants groups are planted together (i.e. trees are planted together). Trees are spaced 10’ apart, shrubs 6’ apart and herbaceous perennials 4’ apart. Little Rock site was planted on April 21, 2000; Fayetteville was planted on April 27, 2000; Hope planted on April 20, 2000. Plants at all three sites are irrigated as needed using drip tape. Plants were fertilized and mulched after planting. Post-emergent herbicides were used at all three test sites. No disease or insect control was implemented in 2001. The Acer and Eucommia were pruned following final growth measurements to establish a tree-like habit. Pruning consisted of removing the bottom 1/3 of limbs. Final growth measurements were taken at Little Rock on November 2; Fayetteville on November 13; and Hope on November 9.

Plants at the Little Rock site do receive a few hours of shade generally during the morning hours. Fayetteville and Hope are very exposed, full sun sites. The Fayetteville site is characterized by consistent winds.

Weather for 2001 at all three test sites is summarized (see attached graph). December 2000 saw record cold in Fayetteville much to the dislike of some of the plants in the trial.

™ Flowerwood Nursery donated 3-gal plants. The winter of 00/01 proved to be a good test for this plant. Both cultivars of Indian hawthorn suffered severely at Fayetteville (USDA zone 6) but are growing well at Hope and Little Rock. Flowering at Little Rock began on April 23 and ended in late May. Average plant size at Little Rock and Hope is 22" tall by 36" wide.

™ Flowerwood Nursery donated 3-gal plants. Similar comments to the above as far as cold hardiness. Flowering period in Little Rock was nearly identical to the above except that a significant re-bloom was noted in September. Leaves on Olivia^TM are distinctly different from Eleanor Taber^TM. Leaves on Olivia^TM are almost round (rounded-ovate) and slightly coarser than Eleanor Taber^TM. Average plant size at Little Rock and Hope is 23" tall by 36" wide.

Flowerwood Nursery donated 3-gal plants. Again, the 00/01 winter was a great test winter for broadleaf evergreens including Ternstroemia. All 3 plants were killed at Fayetteville. The most significant increase in growth was observed at Little Rock. Flowers were not observed at any location. Plants displayed a beautiful burgundy color in the outer most foliage in late fall. Average plant size at Hope and Little Rock is 35" tall by 40" wide.

One-gallon plants were purchased from Pine Ridge Nursery, London, AR. This plant is a real dilemma for the program. Plants are growing very vertical and would benefit from being severely cut back to encourage more branching, however, protocol for the trial does not allow for intervention pruning except for trees. We also feel that this plant would benefit in Arkansas from at least partial shade.

All 3 plants died at Fayetteville. Growth was not outstanding at either Little Rock or Hope. Flowers, which are obviously not showy, began to appear at Little Rock in mid-June and continued sporadically for the next 2 months. Average plant size in Little Rock and Hope is 35" tall by 20" wide.

Diervilla lonicera ‘Copper’

One-gallon plants were initiated at UofA by cutting propagation from a plant purchased from Arborvillage, Holt, MO. Plants put on exceptional growth at all three sites this year. Growth was best at Hope and Fayetteville. Flowering in Little Rock began in early May and continued through early September. Flowering in Fayetteville begins in mid May and peaks on the 1^st of June. Plants re-bloom beginning in August. The flower display is moderately showy. In Fayetteville, plants exhibited attractive fall color this year, a dark burgundy-red. Average plant size is 36" tall by 71" wide.

One quart plants originated from UofA cutting propagation from a plant purchased from Wilkerson Mill Gardens, Palmetto, GA. Growth rate was greatest at Little Rock and least at Fayetteville. Plants in Fayetteville were killed to the ground during the 00-01 winter, but new growth emerged from the base of the plant. Flowers were not observed at any location in 2001. The plant, with very small fine textured leaves, averages 20" tall by 46" wide. On some plants the interior of the plant is beginning to open up.

One quart plants were donated by North Carolina State University. Janet Carson had seen this plant used extensively during a visit to Raleigh in 1999. All 9 plants were surprisingly all killed during the winter of 00/01.

Bare-root plants were donated by Bailey Nursery. Plants demonstrated a substantial increase in size in 2001. The most significant increase in size was at Little Rock, followed by Fayetteville, and finally Hope. Due to a planting error on our part we had to move 2 plants from Hope to Little Rock rather late in 2000. This procedure set 2 or the 3 Little Rock plants back severely, and contributed to the death of one plant. Average plant size is 43" tall by 78" wide. Plants in Little Rock flowered in early April. Plants in Fayetteville flowered in early April also. Fall color on the plants in Fayetteville was attractive, although caterpillars defoliated one plant.

One quart plants originated from UofA cutting propagation from a plant purchased from Wilkerson Mill Gardens, Palmetto, GA. The plant was a recommendation by Ewa Nelson, Morningside Nursery. I have been impressed with its glossy foliage, nice flower display, and tight plant habit.

All 3 plants died at Fayetteville. However, it should be noted that larger plants, not in the official trial, that are planted on campus did survive the winter. Plants grew best at Little Rock and with moderate growth at Hope. Flowering began at Little Rock on April 2 and lasted for 2 weeks. Average plant size at Little Rock and Hope is 22" tall by 32" wide.

Bareroot plants were donated by Bailey Nursery. Cameron Rees of Skinner Nursery, Topeka, KS recommended this plant. Cameron spoke highly of the dark green leaves and plant habit.

The rate of plant growth was very good at all three sites. Plant growth was best in Little Rock followed by Fayetteville and the least growth in Hope. Flowering began in Little Rock on March 14 and lasted until early April. Flowering in Fayetteville started on April 5th and lasted until April 10^th. Here, the floral display was not impressive. The plant is more upright at this point than spreading. Average plant size in 46" tall by 36" wide.

One gallon plants originated from UofA cutting propagation. The source plant was from Woodlanders Nursery, Aiken, SC. This species is one of the parents of Abelia x grandiflora. Plants grew exceptionally well at Hope and Little Rock this year. The flower display was very noteworthy. The white or very soft pink flowers appeared in late June and continued through at least late August. Attractive soft pink calyxes followed the flowers giving the impression that the plant was still in bloom. This lasted until a very hard freeze. It is hard to separate the overall effect of the flowers and the pink calyx. Flowering began in Little Rock on June 11 and continued for at least several months. Flowering in Fayetteville began in mid-July, much later than plants in Little Rock. In Fayetteville, the plants had been killed to the ground during the winter. One plant did not begin to flower until early September. Average plant size is 36" tall by 51" wide.

One-gallon plants were donated by J. Frank Schmidt Nursery. All 3 plants died at Fayetteville during 2001. Trees in Hope and Little Rock grew exceptionally well. Trees at Hope and Little Rock increased their height by 39" and trunk caliper by 0.65".

Bareroot trees (4-5’ BR) were donated by J. Frank Schmidt Nursery. This tree struggled statewide during the first year. Part of the problem may be related to the size of the bareroot trees received and our late date for planting. Based on experience with bareroot plants (Viburnum x ‘Emerald Triumph’) we suggest potting BR plants up into containers or placing in the field much earlier in the season.

Trees are struggling at Hope and Fayetteville. Even though the growth rate is favorable at Little Rock the habit of this tree is not a positive attribute. Leaves are coarse in texture and few in number.

The Ornamentals team would like to express their sincere appreciation to the cooperating nurseries (J. Frank Schmidt Nursery, Bailey Nursery, and Flowerwood Nursery) for donating the plants for this seasons trial and to the Arkansas Nurserymen’s Association for financial support.

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