PLANT HEALTH CARE (PHC) MANAGEMENT
Compare the photograph on the left to the photograph of the same Colorado blue spruce tree (Picea pungens) on the right.
I took these pictures about 3 weeks apart, after I was first contracted by the homeowner to diagnose the cause of the dieback and poor color of the tree.
Plant Health Care (PHC) management is an effective and cost efficient strategy of prioritizing options for restoring health, vigor, vitality, and color of trees. To make the correct decisions that solve the problem to the tree owner’s satisfaction, the following “recipe” of actions must be incorporated:
- Correctly identify the tree species
- Gather all pertinent information about the plant site (soils/herbicide applications/weather events/change of season/etc)
- Observe and identify any signs and symptoms of insects, mites, or diseases
- Logically determine “what caused what”
- Prescribe corrective management options based on the gathered information
NOTE: the terms “signs and symptoms” are accented in bold font and hi-lighted in yellow. The reason I’ve called attention to these two terms is that they are the essence of a successful prescriptive PHC management strategy.
This is important to know…diagnosing tree disorders on the basis of symptoms can be misleading as symptoms can be caused by numerous factors. Symptoms are the appearances or reactions of the tree to a pest agent such as humans, insects, mites, and diseases.
Signs are direct physical evidence of a pest, or the byproduct of its activity. Signs are really useful in determining the origin of symptoms.
The following photograph of a dogwood twig best illustrates this important information about PHC diagnostics using symptoms & signs.
So, don’t forget this valuable information…a correct use of PHC diagnostics that pinpoints the prescriptive remedy will save you time, money, and a lot of unneeded frustration by the alternative method of applying pesticides based on guesswork or an opinion by an untrained, uneducated, and inexperienced arborist who is not interested in taking a close look at the big picture to solve your tree problem.
Still not convinced that correctly identifying tree health problems by analyzing the signs and symptoms really works?
Ok…then try to diagnose what is going on with some aspen leaves, based only on symptoms: the plant’s reaction to a pest agent.
So, what have you deduced from observing the different symptoms of the four aspen leaves?
Are the symptoms caused by:
- Cold weather?
- Hot weather?
- Herbicide damage?
- A normal change of the season?
- Over watering?
- Not enough water?
- Lack of soil nutrients?
- A combination of all of the listed agents?
And…are any of these symptoms normal or abnormal conditions for an aspen leaf?
Without looking for signs- direct, physical evidence, correctly diagnosing this problem is impossible, and costly!
- Spray for insects?
- Spray for mites?
- Inject for fungal disease?
- Apply fertilizer?
- Step up watering?
- Back off watering?
- Blame the lawn technician who applied lawn weed-killer earlier in the season?
Please check out my Contact Page for more information or to set up an appointment to correctly diagnose any tree problems that you might have.
The following list of common pest agents I’ve found on trees this time of year may help diagnose some of your particular tree problems.
*I will be adding more content to this section later in the season. And, I have lots of interesting & informative photos to show!