National Elm Trial in Kentucky

Transcription

1 National Elm Trial in Kentucky Established in 2005 and 2006 in Lexington, KY Site is located on an open, grassy area on Maury silt loam soil Visitors are welcome. The location is on Alumni Drive directly across the road from the entrance to the University Arboretum Publications: Resistance of Landscape-Suitable Elms to Japanese Beetle, Gall Aphids, and Leaf Miners, with Notes on Life History of Orchestes alni and Agromyza aristata in Kentucky. Jennie Condra, Cristina Brady, Daniel Potter Relative resistance or susceptibility of landscape-suitable elms (Ulmus spp.) to multiple insect pests Daniel Potter and Carl Redmond Insects noted: Japanese Beetle, European Elm Flea Weevil, European fruit lecanium, Scale Insects, Aphids, Leaf Mining Weevils and flies, European Sawfly Favorites: Valley Forge, Prospector and New Horizon

2 Alumni Drive Rep 1 Plot Layout for Rep One X 19X X 2X Soccer Field 7 Upper physical damage X= tree died Soggy area

3 Rep 2 & 3 Plot Map for Reps two and three Alumni Drive 12X 12X-branch dieback, phytoph root rot Soccer Field 6 Lower 2 8X X X Tree cultivars #5 and 14 were replaced in Rep 2 20X March 06, while cultivars #2 reps 1, 3 were not. 7 1 April 06 cultivars 15,16, 17 were planted X- 18X Nectria canker trunk bark peeling X 16- dead 2011 spring X 6X X trunk bark peeling X 7 2X 2007 Baseball field 10 In 2012, Rep 3 (red font) was moved alongside the fence (red arrow) due to installation of a large drainage basin (red circle). Some trees did not transplant successfully, others were stunted. Thus, we are no longer taking measurements of this rep.

4 Sewer Plot layout for Reps four and five Alumni Drive Rep X 20 12X X X Water Baseball Field Rep 5 Water X X 8X 7 16X 18X 10 19X 5X X 11X

5 National Elm Trial Kentucky Contacts Dr. Nicole Ward Gauthier Dept. of Plant Pathology University of Kentucky Lexington KY Dr. Dan Potter Dept. of Entomology University of Kentucky Lexington, KY

6 Kentucky Cultivar List Cultivar Number Cultivar Name Parentage 1 Emerald Sunshine U. propinqua 2 Emer II Allee U. parvifolia 3 Frontier U. carpinifolia X U. parvifolia 4 Homestead U. glabra X U. carpinifolia X U. pumila 5 Morton Glossy Triumph U. pumila X U. japonica X U. wilsoniana 6 Morton Plainsman Vanguard U. pumila X U. japonica 15,16,17 planted ,19,20 planted Morton Red Tip Danada Charm 8 Morton Stalwart Commendation U. japonica X U. wilsoniana U. carpinifolia X U. pumila X U. wilsoniana 9 Morton Accolade U. japonica X U. wilsoniana 10 New Horizon U. pumila X U. japonica 11 Patriot (U. glabra X U. carpinifolia X U. pumila) X U. wilsoniana 12 Pioneer U. glabra X U. carpinifolia 13 Prospector U. wilsoniana 14 Valley Forge U. americana 15 Princeton U. americana 16 Jefferson U. americana 17 New Harmony U. americana 18 Athena Classic lace bark U. parvifolia 19 Everclear lace bark U. parvifolia 20 Prarie expedition elm (ND)

7

8 Diameter Growth/Year

9 Height Growth/Year

10 Crown Width Growth/Year

11 Cultivar Ratings

12 Emerald Sunshine (Ulmus propinqua) Emer II Allee (U. parvifolia) Survival: 80% Diameter at 1.4m (cm): 7.6 Height (m): 5.8 Crown shape: Oval Crown width (m): 2.3 European fruit lecanium scale (mean per 1.5m of twigs): 10 European Elm Scale (mean per 1.5m of twigs and lower trunk): 0 Japanese Beetle (% Leaf area loss): 15 *European elm flea weevil abundance (Orchestes almi): Low Survival: 60% Diameter at 1.4m (cm): 9.2 Height (m): 5.2 Crown shape: Round Crown width (m): 4.4 European fruit lecanium scale (mean per 1.5m of twigs): 5 European Elm Scale (mean per 1.5m of twigs and lower trunk): 0 Japanese Beetle (% Leaf area loss): 10 *European elm flea weevil abundance (Orchestes almi): High

13 Frontier (Ulmus carpinifolia X U. parvifolia) Homestead (U. glabra X U. carpinifolia X U. pumila) Survival: 100% Diameter at 1.4m (cm): 6.8 Height (m): 5.0 Crown shape: Oval Crown width (m): 2.7 European fruit lecanium scale (mean per 1.5m of twigs): 5 European Elm Scale (mean per 1.5m of twigs and lower trunk): 10 Japanese Beetle (% Leaf area loss): 30 *European elm flea weevil abundance (Orchestes almi): High Survival: 100% Diameter at 1.4m (cm): 9.6 Height (m): 6.0 Crown shape: Oval, Round Crown width (m): 3.2 European fruit lecanium scale (mean per 1.5m of twigs): 10 European Elm Scale (mean per 1.5m of twigs and lower trunk): 5 Japanese Beetle (% Leaf area loss): 70 *European elm flea weevil abundance (Orchestes almi): High

14 Morton Glossy Triumph TM (U. pumila X U. japonica X U. wilsoniana) Morton Plainsman Vanguard TM (U. pumila X U. japonica) Survival: 80% Diameter at 1.4m (cm): 9.4 Height (m): 5.4 Crown shape: Oval Crown width (m): 3.0 European fruit lecanium scale (mean per 1.5m of twigs): 10 European Elm Scale (mean per 1.5m of twigs and lower trunk): 10 Japanese Beetle (% Leaf area loss): 45 *European elm flea weevil abundance (Orchestes almi): Low Survival: 80% Diameter at 1.4m (cm): 8.2 Height (m): 5.0 Crown shape: Vase Crown width (m): 3.6 European fruit lecanium scale (mean per 1.5m of twigs): 15 European Elm Scale (mean per 1.5m of twigs and lower trunk): 0 Japanese Beetle (% Leaf area loss): 70 *European elm flea weevil abundance (Orchestes almi): High

15 Morton Red Tip Danada Charm TM (U. japonica X U. wilsoniana) Morton Stalwart Commendation TM (U. carpinifolia X U. pumila X U. wilsoniana) Survival: 100% Diameter at 1.4m (cm): 12.8 Height (m): 5.8 Crown shape: Vase Crown width (m): 3.4 European fruit lecanium scale (mean per 1.5m of twigs): 10 European Elm Scale (mean per 1.5m of twigs and lower trunk): 10 Japanese Beetle (% Leaf area loss): 45 *European elm flea weevil abundance (Orchestes almi): High Survival: 60% Diameter at 1.4m (cm): 10.1 Height (m): 5.4 Crown shape: Round Crown width (m): 3.2 European fruit lecanium scale (mean per 1.5m of twigs): 13 European Elm Scale (mean per 1.5m of twigs and lower trunk): 10 Japanese Beetle (% Leaf area loss): 60 *European elm flea weevil abundance (Orchestes almi): Low

16 Morton Accolade (U. japonica X U. wilsoniana) New Horizon (U. pumila X U. japonica) Survival: 100% Diameter at 1.4m (cm): 9.6 Height (m): 5.0 Crown shape: Round Crown width (m): 3.2 European fruit lecanium scale (mean per 1.5m of twigs): 20 European Elm Scale (mean per 1.5m of twigs and lower trunk): 0 Japanese Beetle (% Leaf area loss): 60 *European elm flea weevil abundance (Orchestes almi): Low Survival: 100% Diameter at 1.4m (cm): 12.6 Height (m): 5.9 Crown shape: Oval Crown width (m): 3.2 European fruit lecanium scale (mean per 1.5m of twigs): 5 European Elm Scale (mean per 1.5m of twigs and lower trunk): 50 Japanese Beetle (% Leaf area loss): 25 *European elm flea weevil abundance (Orchestes almi): High

17 Patriot (U. glabra X U. carpinifolia X U. pumila) X U. wilsoniana Pioneer (U. glabra X U. carpinifolia) Survival: 40% Diameter at 1.4m (cm): 10.0 Height (m): 5.8 Crown shape: Vase Crown width (m): 3.3 European fruit lecanium scale (mean per 1.5m of twigs): 50 European Elm Scale (mean per 1.5m of twigs and lower trunk): 25 Japanese Beetle (% Leaf area loss): 45 *European elm flea weevil abundance (Orchestes almi): Moderate Survival: 20% Diameter at 1.4m (cm): 5.1 Height (m): 3.7 Crown shape: Round Crown width (m): 2.8 European fruit lecanium scale (mean per 1.5m of twigs): 15 European Elm Scale (mean per 1.5m of twigs and lower trunk): 10 Japanese Beetle (% Leaf area loss): 65 *European elm flea weevil abundance (Orchestes almi): Moderate

18 Prospector (U. wilsoniana) Valley Forge (U. americana) Survival: 80% Diameter at 1.4m (cm): 8.9 Height (m): 4.5 Crown shape: Oval and Vase Crown width (m): 3.0 European fruit lecanium scale (mean per 1.5m of twigs): 20 European Elm Scale (mean per 1.5m of twigs and lower trunk): 20 Japanese Beetle (% Leaf area loss): 40 *European elm flea weevil abundance (Orchestes almi): High Survival: 80% Diameter at 1.4m (cm): 9.8 Height (m): 6.2 Crown shape: Round and Oval Crown width (m): 4.5 European fruit lecanium scale (mean per 1.5m of twigs): 75 European Elm Scale (mean per 1.5m of twigs and lower trunk): 130 Japanese Beetle (% Leaf area loss): 15 *European elm flea weevil abundance (Orchestes almi): Low

19 Princeton (U. americana) Jefferson (U. americana) These Jefferson reps were found to be the same cultivar as Princeton Survival: 100% Diameter at 1.4m (cm): 10.7 Height (m): 7.6 Crown shape: Oval Crown width (m): 2.4 European fruit lecanium scale (mean per 1.5m of twigs): 20 European Elm Scale (mean per 1.5m of twigs and lower trunk): 55 Japanese Beetle (% Leaf area loss): 25 *European elm flea weevil abundance (Orchestes almi): Low Survival: 60% Diameter at 1.4m (cm): 7.5 Height (m): 5.8 Crown shape: Vase Crown width (m): 2.1 European fruit lecanium scale (mean per 1.5m of twigs): 30 European Elm Scale (mean per 1.5m of twigs and lower trunk): 25 Japanese Beetle (% Leaf area loss): 45 *European elm flea weevil abundance (Orchestes almi): Low

20 New Harmony (U. americana) Athena Classic Lacebark Elm (U. parvifolia) Survival: 100% Diameter at 1.4m (cm): 8.9 Height (m): 6.5 Crown shape: Oval Crown width (m): 2.0 European fruit lecanium scale (mean per 1.5m of twigs): 40 European Elm Scale (mean per 1.5m of twigs and lower trunk): 190 Japanese Beetle (% Leaf area loss): 10 *European elm flea weevil abundance (Orchestes almi): Moderate Survival: 60% Diameter at 1.4m (cm): 5 Height (m): 3.25 Crown shape: Oval Crown width (m): 1.9 European fruit lecanium scale (mean per 1.5m of twigs): 20 European Elm Scale (mean per 1.5m of twigs and lower trunk): 0 Japanese Beetle (% Leaf area loss): 10 *European elm flea weevil abundance (Orchestes almi): High

21 Everclear Lacebark Elm (U. parvifolia) Lewis and Clark Prairie Expedition (U.americana) Survival: 40% Diameter at 1.4m (cm): 5.5 Height (m): 4.7 Crown shape: Oval Crown width (m): 1.1 European fruit lecanium scale (mean per 1.5m of twigs): 25 European Elm Scale (mean per 1.5m of twigs and lower trunk): 0 Japanese Beetle (% Leaf area loss): 5 *European elm flea weevil abundance (Orchestes almi): Moderate Survival: 80% Diameter at 1.4m (cm): 6.0 Height (m): 4.1 Crown shape: Vase Crown width (m): 2.4 European fruit lecanium scale (mean per 1.5m of twigs): 30 European Elm Scale (mean per 1.5m of twigs and lower trunk): 75 Japanese Beetle (% Leaf area loss): 20 *European elm flea weevil abundance (Orchestes almi): Moderate

22 Images of the Kentucky National Elm Trial soon after planting

23 Damages *Abundance of European elm flea weevil equals the mean number of mines found on leaves Low<50 Moderate= High>100 Resistant to Agromyza aristata (2009): Emer II Allee Athena Classic Lacebark Everclear Lacebark Emerald Sunshine Morton Plainsman Vanguard Morton Red Tip Danada Charm Morton Stalwart Commendation Patriot Frontier Homestead Pioneer Resistant to Kaliofenusa ulmi (2009): Valley Forge Jefferson New Harmony Lewis and Clark Prairie Expedition Emer II Allee Athena Classic Lacebark Everclear Lacebark Emerald Sunshine

24 PEST MANAGEMENT - DISEASES AND INSECTS National Elm Trial - Kentucky Data, 2015 Nicole Ward Gauthier and Ed Dixon, Plant Pathology; Dan Potter, Entomology; Jerry Hart PPD- Grounds; and William Fountain, Horticulture Nature of Work The National Elm Trial was established to evaluate landscape-suitable elm cultivars for disease and insect tolerance and for horticultural characteristics at 15 locations nationwide from California to Vermont and south to Kentucky. Locally, 14 elm cultivars were planted April 13-15, 2005 in a grassy area on the University of Kentucky campus in Lexington. An additional three cultivars were planted in April, 2006 and three more cultivars in April, Plots were located south and east of the sports complex across from the U.K. Arboretum entrance along Alumni Drive (North 38 deg, 1 min; West 84 deg, 30 min, elev. 990 ft). The site had been graded for construction some years before and consisted of a mixture of topsoil, subsoil, and construction debris. In the planting, a double-allée, each cultivar was replicated five times and arranged in a randomized complete block design. Additional randomized space was left in each block for elm cultivars to be planted in future years. Trees were staked as needed, watered during dry periods during the first three years, and all trees were mulched over grass that had been killed with an application of Roundup herbicide. The twenty elm cultivars planted for this study include the following: 1. JFS Bieberich Emerald Sunshine - Ulmus propinqua 2. Emer II Allee - U. parvifolia 3. Frontier - U. carpinifolia X U. parvifolia 4. Homestead - U. glabra X U. carpinifolia X U. pumila 5. Morton Glossy Triumph - U. pumila X U. japonica X U. wilsoniana 6. Morton Plainsman Vanguard - U. pumila X U. japonica 7. Morton Red Tip Danada Charm - U. japonica X U. wilsoniana 8. Morton Stalwart Commendation - U. carpinifolia X U. pumila X U. wilsoniana 9. Morton Accolade - U. japonica X U. wilsoniana 10. New Horizon - U. pumila X U. japonica 11. Patriot - (U. glabra X U. carpinifolia X U. pumila) X U. wilsoniana 12. Pioneer - U. glabra X U. carpinifolia 13. Prospector - U. wilsoniana 14. Valley Forge - U. americana 15. Princeton - U. americana 16. Jefferson - U. americana 17. New Harmony - U. americana 18. Athena - U. parvifolia 19. Everclear - U. parvifolia 20. Prairie Expedition - U. americana Trees came from the nursery in 2005, 2006, and 2007 as bare root transplants about 5-8 ft tall (except Jefferson which was much smaller). Elms in all plots were pruned in early spring 2008 to eliminate crossing and broken branches and to establish a central leader. In 2015 the plots received above normal rainfall in April and July but below normal rainfall in May, June, and August. Construction of a blacktop running path occurred in June 2015 just 5 feet from one

25 row of trees in rep one and two. On September 18, 2015 tree trunk diameters were measured with a caliper and tree height and width were determined (Table 1). We have lost trees over the last few years due to Phytophthora root rot, Necria canker, and two trees were blown over in a storm. Some of the tree deaths may be partially due to weakened trees from the 2007 April freeze or to drought in subsequent years. Japanese beetle damage, leaf miner and scale infestations were assessed by Entomologist collaborators and these results are reported elsewhere. Results and Discussion Results from the elm plots are presented in Table 1. One rep of trees was moved in early January 2013 to make way for irrigation runoff pond, so data from those trees was not taken. All of the elm cultivars are well established and are increasing in height, width, and trunk diameter. Although differences in insect pest levels are observed most years, as of 2014 there have been no incidences of bacterial leaf scorch, elm yellows, or Dutch elm disease. Table 1. Size of elms, *Trunk diameter taken at 4.5 ft, on September 18, One rep of trees moved in early January 2013 to make way for irrigation runoff pond, so data from those trees was not taken. Average height in feet; Average crown width in feet; Average trunk diameter, inches dbh*; Cultivar number and name (Increase from 2014) 1. JFS Bieberich 23.3 (4.3) 8.0 (0.5) 3.63 (0.27) 2. Emer II Allee 24.3 (7.0) 15.5 (0.3) 4.90 (0.27) 3. Frontier 21.3 (3.7) 11.5 (0.8) 4.37 (0.70) 4. Homestead 24.5 (5.3) 13.3 (0.8) 5.40 (0.33) 5. Morton Glossy 23.3 (4.0) 13.3 (0.7) 6.33 (0.67) 6. Morton Plainsman 19.0 (1.8) 13.4 (0.8) 4.60 (0.28) 7. Morton Red Tip 23.8 (5.0) 11.9 (0.5) 7.03 (0.65) 8. Morton Stalwart 24.0 (4.5) 13.0 (0.3) 6.25 (0.60) 9. Morton Accolade 20.3 (2.8) 12.3 (0.8) 5.20 (0.40) 10. New Horizon 25.0 (5.3) 12.0 (0.9) 7.08 (0.43) 11. Patriot 27.5 (7.5) 13.0 (1.0) 5.45 (0.45) 12. Pioneer 14.0 (1.0) 11.0 (1.0) 2.90 (0.40) 13. Prospector 20.0 (4.0) 11.0 (0.5) 5.13 (0.10) 14. Valley Forge 29.3 (7.7) 16.8 (0.7) 6.27 (0.93) 15. Princeton 28.5 (3.3) 10.3 (0.5) 7.23 (1.05) 16. Jefferson 29.3 (8.3) 10.2 (1.0) 5.33 (1.40) 17. New Harmony 29.5 (6.8) 7.9 (0.6) 5.73 (0.85) 18. Athena Classic 14.0 (2.2) 7.5 (0.5) 3.07 (0.33) 19. Everclear 19.0 (3.5) 4.5 (0.5) 2.90 (0.15) 20. Prarie Expedition 16.3 (1.7) 9.7 (0.3) 4.07 (0.17)

26 Table 2. Fall color and tree shape. Significance to Industry The widespread use of elms in the landscape has been lost largely due to Dutch elm disease. Knowledge of how elms perform in Kentucky in the face of diseases such as Dutch elm disease, elm yellows, and bacterial leaf scorch; and insect pests such as Japanese beetles, elm leaf miners and other pests will benefit arborists and the landscape maintenance and nursery industries. Cultivar number and name Fall color Shape Number of trees 1. JFS Bieberich Green- yellow Upright oval 3 2. Emer II Allee Yellow to red Round 2 3. Frontier Burgundy Oval 4 4. Homestead Green- yellow Oval-round 4 5. Morton Glossy Yellow to brown Upright oval 3 6. Morton Plainsman Yellow gold Vase 3 7. Morton Red Tip Yellow to brown Vase 4 8. Morton Stalwart Yellow Round 2 9. Morton Accolade Yellow-brown Round New Horizon Green yellow Upright oval Patriot Green yellow Vase Pioneer Green yellow Round Prospector Green - yellow Vase-oval Valley Forge Yellow- gold Round-oval Princeton Yellow Oval Jefferson Yellow Upright vase New Harmony Yellow Upright oval Athena Classic Yellow Oval Everclear - Upright oval Prarie Expedition Yellow Vase 3

27 References Condra, J. M., C. M. Brady and D. A. Potter Resistance of Landscape-Suitable Elms to Japanese Beetle, Gall Aphids, and Leaf Miners, with Notes on Life History of Orchestes alni and Agromyza aristata in Kentucky. Arboriculture and Urban Forestry. 36: Potter, D. A. and C. T. Redmond Relative resistance or susceptibility of landscape-suitable elms (Ulmus spp.) to multiple insect pests. Arboriculture and Urban Forestry. 39: