It is time to sharpen your plant health diagnostic skills. Whether it is turf, ornamentals, or arborcare, several factors should be considered when diagnosing a problem.
Too many times, things unseen (below grade) are directly responsible for some of the issues on the surface. Considering that statement, make sure to not only focus in on the area directly affected, but take a few steps back to look at the bigger picture. Make sure to note non-infectious circumstances.
Is the issue Biotic or Abiotic?
Causal agents of plant problems tend to fall into two categories.
Biotic issues are generally associated with living things including diseases, insect feeding, and such. These are usually a bit easier to manage because Ewing’s plant protectant manufacturer partners produce outstanding chemistries to manage these issues from both a preventative and curative approach.
Abiotic problems are those that arise from non-living factors. They include things like wind, drought stress, flooding, traffic, compaction, water repellent soils, sunscald, freeze injury, nutrient deficiency, salt accumulation, mower damage, equipment leaks, heat, and allelopathy.
This is a very important concept to consider because your diagnosis depends on it. While certain disease, weed, and insect pressure can be more intense to plants already stressed, the predisposing factors still point back to some abiotic stressor.
5 General Rules of Diagnostics
In beginning of the diagnostic journey, there may be some tell-tale signs that what you are seeing is not biotic-related but more so the result of something that physically happened in the area.
Some of those general rules to keep in mind:
- Biotic issues (disease) don’t kill in straight lines
- Diseases and insect problems do not create a perfect circle of damage
- Abiotic problems can be seen across several species of plants on the same site, biotic problems tend to stick to the same species
- Abiotic problems tend to not spread over time; insect and diseases problems can spread over time
- Biotic problems will often show presence of signs including fungal growth, insect presence, or nematode cysts
Key Steps and Questions to Ask to Get to the Root of the Problem
Key steps to take in these situations are to identify the host or hosts, look for identifying factors, inspect the entire plant (both above and below ground), and inspect the site. In some instances, the question will stop at host ID, where the turf or ornamental is not well-adapted to the area. A perfect example is where zoysia grass has spread into cool season lawns.
It also might be a misunderstanding of growth patterns—for example, deciduous trees that look like they should not lose their leaves including dawn redwood, European larch, deciduous azalea species, or common bald cypress. Sometimes, it really pays to ask the site owner or manager questions.
- Ask or inspect the terrain—is it sloped, does it have low spots, or is it well-drained?
- How about wind, reflective heat, excessive shade?
- Was anything applied to the area recently?
- When did the problem first show up?
- Have there been any cultural practices performed recently?
- Are the symptoms uniform across the area
- Has the soil been tested?
- Can you get a probe into the ground?
- Is there buried debris? (This is a big one on new construction.)
Tools Can Help in the Diagnostic Process
Bringing some simple tools with you can help you answer many of the above questions. They include:
- Soil probe or shovel to determine root depth, compaction, and soil water content
- Hand lens to see disease signs, insects, or dull mower blades
- Mallet or hammer to tap test trees for decay or hollowing
- Pitchfork to find below-grade debris
Finally, take pictures, lots of pictures. Get shots from close range and take steps back to get a look at the entire area. Take photos of the surrounding areas, trees, landscape beds, new construction, and anything else that may just look like it is important.
If you’re experiencing issues, you can Lean on Ewing for diagnostic help. Call or text our new T&O Solutions Helpline, 480-669-8791, from 7 a.m. to 8 p.m. EST Monday through Friday, email your photos and questions to firstname.lastname@example.org, or visit your local Ewing location today!
For more solutions, visit our Turf & Ornamental Tech Tips page.