The problem-solving process: Details

The challenges of diagnosing abiotic disorders are many:

• Abiotic (nonliving) and biotic (living) agents can cause injury to landscape plants, so knowing exactly what caused a particular problem sometimes is difficult.
• Distinguishing between abiotic and biotic disorders can be difficult in some instances.
• A landscape may exhibit high variability in plant species, soil quality, microclimate, and sun exposure.
• A problem observed in a landscape often can have multiple causes or factors.
• Chronic problems may express only subtle symptoms.

Accurately diagnosing plant problems depends on the following:

• Observing subtle differences from the normal in plant appearance or the surrounding environment
• Possessing good knowledge of plants, soil, climate, cultural practices, pests, diseases, and their interactions
• Having accurate information about the recent history of affected plants, the site, the climate, and cultural practices
• Using a few simple tools to diagnose the problem; these may include: a sturdy pocketknife, shovel, pruning shears, hand lens, and digital camera
• Using analytical approaches (testing of water, soil, and plant tissue) to diagnose difficult problems

General diagnostic checklist and strategy:

• How many plants are affected? What species are they?
• Is there a pattern spatially, and are the problem areas grouped in relation to topography or prevailing wind directions?
• Does the site appear to be favorable for the plants?
• Are there depressions where frost often is prevalent or where drainage is poor?
• Are soils at the site soggy, moist, or dry?
• Does the soil have normal color and odor, or is it dark gray in color with aroma like rotten eggs?
• Has there been recent construction, paving, excavation, or soil filling?
• Where are the gas, water, sewer, septic fields located?

Step-by-step diagnostic strategy that could lead to corrective actions specific to the problem:

• Identify the plants — Determine genus, species, and, if appropriate, cultivar
• Identify the symptoms — Examine the injured part and list all symptoms
• Inspect the whole plant — Examine all parts of the plant, not just the injured area
• Inspect the site — Look for conditions that may contribute to the injury
• Look for patterns in the symptoms
• Investigate the site's history of plant management
• Synthesize the information collected and identify the most likely causes
• Test likely causes — analyses of soil, water, and plant tissue are frequently valuable for accurate diagnosis

« Previous section

Next section »