Barbara J. Bromley, Mercer Co. Horticulturist 97
NATURE-CAUSED STRESSES
- Moisture extremes (drought, flooding)
- Temperature extremes (rapid fluctuations, excessive cold/heat in any season)
- Storm damage (wind, lightning)
- Insects, mites, slugs
- Diseases (fungal, bacterial, viral, nematodes)
- Animals (dogs, cats, voles, squirrels, deer, rabbits, woodchucks)
- Air pollutants (ozone, sulfur dioxide, PAN)
- Acid rain
PEOPLE-CAUSED STRESSES
Soil problems
- nutrient deficiencies or excesses
- improper pH – too acid or too alkaline soil reaction compaction from pedestrian traffic or machinery
- poor drainage (lack of percolation test, too much cement and asphalt)
Improper plant selection
- hardiness
- ultimate landscape size
- inappropriate genus, species, or variety
- inattention to pest resistance
Improper plant placement
- nearness to buildings, traffic areas, other plants
- nearness to downspouts
- wrong exposure: north, south, east, west, shade, sun
Improper planting and post-transplant care
- depth of planting
- soil testing and preparation
- root treatment pot-bound material, broken roots, girdling roots
- follow-up care: mulching, staking, fertilizing, watering
Improper pruning – timing, technique, equipment
Improper irrigation – too frequent, too shallow, not at all, wrong time of day
Wounds
- girdling wires
- vandalism or accident
- equipment injury: nylon string trimmers, lawn mowers (“mower blight”)
Chemical injury “READ THE LABEL”
- herbicide misuse
- other pesticide or chemical misuse
- road and sidewalk deicing salts
- miscellaneous chemicals: liquor, oil, gasoline, etc.
Construction and excavation damage (“builders blight”)
- grade changes: “Fill Kills”
- soil compaction
- chemical injuries (spilled lime, paint, etc.)