The Disease Triangle Tree Planting and Tree Health 1. Susceptible host plant 2. Active pathogen Northeast Indiana Landscape and Turf Seminars Purdue University Cooperative Extension Service, Allen County Friday, November 14, 2014 3. Favorable climate 4. Time Time Host Plant Pests and diseases Primary strong or virulent pests and pathogens Will cause damage even on healthy plants Often require host plant to complete its lifecycle Secondary weak pests and pathogens May require stressed plants Do not need a host plant to complete lifecycle Stress and plant disease Disease triangle requires a susceptible host Stress and deficit can make plants more susceptible Understand what are primary and secondary plant health problems Plant Health Care Recommendations for Declining Trees. Bartlett Tree Research Laboratories Technical Report. Stress prevention Immediate stress of transplanting Digging causing root loss Cutting roots to prevent stem-girdling roots Digging and planting seasons Long-term after transplant shock Right plant in the right place Managing problems from planting Maintenance and training Stress prevention Immediate stress of transplanting Digging causing root loss Cutting roots to prevent stem-girdling roots Digging and planting seasons Long-term after transplant shock Right plant in the right place Managing problems from planting Maintenance and training 1
Planting size Root and twig growth Gary W. Watson. Tree Transplanting and Establishment. Arnoldia 1996-7 Winter. Gary W. Watson. Tree Transplanting and Establishment. Arnoldia 1996-7 Winter. Preventing mechanical problems Take the extra steps at planting Remove materials Metal baskets Pull down or remove burlap Don t plant half-way out of ground soup bowl Find the root flare Where are the roots? Seedling root stock production Primary root is pruned adventitious roots Formation of an adventitious root flare deeper in the soil than the natural root flare 2
Deeper is not better Root flare 3 below soil line Suffocating roots Deeper is not better Reduced water Excess moisture on stem University of Florida Not taking extra steps at planting University of Florida, IFAS Not taking extra steps at planting Bare root planting Lighter weight Easily see roots Transport more trees at once Stem-girdling roots (SGR) Symptoms after 10-15 years, pending on size of container Roots resemble spokes on a bicycle SGR are a result of cultural practices Pot-bound trees Adventitious roots Volcano mulching Watering trees like turf 3
Stem-girdling roots Stem-girdling roots Landscape Plants, Univ. of FL Prevent stem girdling roots Remove outer 1.5 of root ball The Garden Professors, Bert Cregg Landscape Plants, Univ. of FL Landscape Plants, Univ. of FL Stress prevention Planting location Immediate stress of transplanting Digging causing root loss Cutting roots to prevent stem-girdling roots Digging and planting seasons Long-term after transplant shock Right plant in the right place Managing problems from planting Maintenance and training Environmental Space for growth Species for disease prevention Courtesy Missouri Botanical Garden PlantFinder Sun exposure Planting location Planting location Winter burn Salt Damage The Alabama Cooperative Extension System Space to grow 4
Planting location Soil ph Missouri Botanical Garden Proper watering prevents many other plant health problems Water Water Water 1 a week Sprinkler for an hour Do not water trees the same way you water turfgrass Rock mulch Compaction Temperature fluctuation Organic matter Embedding in stem Microbe growth inhibited Managing stressed trees Manage even secondary pests, temporarily Remove diseased branches, if possible Avoid excess nitrogen Burn Encourages canopy growth, which roots may not be able to support Growth regulators? You can have a tree without aboveground parts, but not without belowground parts Sanitation is the key When to sanitize? Vascular diseases Cankers Root rots 99 of rubbing alcohol and seconds Hand pruners, shears, weed whips, mowers Between branches, cuts, or trees 5
Sanitation is the key Stephanie Adams Rubbing alcohol (70 or 91%) Lysol (40% alcohol) Bleach (5% solution) Professional, medical, hospital sanitizers The Morton Arboretum sadams@mortonarb.org http://planthealthcare-mortonarb.org/ Facebook.com/treepathologist 6