Just like many tools or techniques available to an aborist, yearly fungicide programs can be used to the benefit of the customer and provider alike, or to the detriment of both, as well as the environment. The key to success is to customize programs to fit the need of the client, not create “one-size-fits-all” services that all of the clients in your database receive. The good news is that if utilized properly, tree fungicide programs allow hard work and training to pay off financially and publicly.

Setting the stage

When you look closely, there are precious few trees that require automatic spray programs to grow well in a landscape. Sure, there are some problematic ones that are high-maintenance species; certain disease-susceptible cultivars of crab apple and some species of pine come to mind. However, overall, the bulk of the specimens on most clients’ properties are not this way.

maintenance error

Look closely at a suspected disease; some problems appear to be pathogenic, but are actually caused by maintenance errors. Photo: John Fech

Before embarking on convincing a customer to agree to a fungicide program, consider other options for the improvement of the tree’s health. For example, if powdery mildew is a problem, removal of nearby undesirable trees to increase airflow may be a possibility. Another might be to replace it with a disease-resistant species or a different cultivar of the same species.

Integrated pest management (IPM) is a set of considerations that can serve as a common-sense guiding force. IPM encourages consideration of all factors that are necessary for a tree to be healthy, such as soil nutrition, pH, planting depth, soil compaction, spacing, hardiness, competition from turfgrass or other trees, inherent disease resistance and soil moisture. Even though it was introduced a few decades ago, IPM is still chic and remains a good vehicle to ensure that trees are provided with all inputs necessary to thrive.

Actually, in most situations, if a tree needs a yearly fungicide treatment program, it’s either a poor choice for the location or some other factor is limiting its performance. Trees planted too deeply are much more prone to root rot, tight spacing often causes foliar disease, and excessive tree and lawn fertilization often causes a greater incidence of aphid infestation and sooty mold infection.

Tree fungicide programs succeed when a need is established as a prerequisite. The most certain need is the presence of the actual infection; the next is when a history of the disease has been reported or observed. Good recordkeeping can be an effective marketing tool for future treatments, especially if a strong pattern of a disease is documented. For example, a moderate cedar-hawthorn rust infection can signal the need for inspection and preventative treatment the following season, especially if the tree is located in a high-visibility area of the landscape.

Tools for checking trees

Checking for decay and other wood pathogens requires a few tools, fortunately, they don’t need to be high-tech or expensive. Photo: John Fech

Spray and pray

With the previous section in mind, do one-size-fits-all/prescheduled programs have a place in good arboricultural care? The answer is no. Unfortunately, when discussing a pest control issue with many of my clients, they indicate that “the tree service guys spray my trees five times a year.” I respond by asking, “What do they spray them for?” The answer: “Well, I don’t know, they just say that they are trying to prevent any problems that may arise.” This, of course, begs the question, “Have you ever had any disease problems?” To which the answer is usually, “No.”

So, with this common scenario in mind, why are these programs in place? In many cases, they tie back to the origins of arboriculture, back to the days of the tree surgeon. When tree care was in its infancy, filling tree voids with concrete and painting pruning wounds were common practices.

As time progressed, arborists and university researchers began challenging conventional wisdom and asking the question, “Why are we doing this, does it really help the tree? In addition to the previous two examples, monthly insect and disease programs were developed, many with good intentions to do everything possible to keep trees healthy. These were programs that involved applying a contact insecticide and fungicide mixture at predetermined times, usually to all trees and shrubs on the property, regardless of the presence or history of actual diseases or insect pests.

The bottom line is: unless a legitimate need has been established, it’s not only poor arboriculture, it’s downright dishonest, bordering on fraudulent, to apply a fungicide to a tree.

staking material

Failure to remove staking material after one growing season can lead to cambial restrictions. Photo: John Fech

Instead, inspect and spray

Instead of one-size-fits-all approaches, design spray programs based on history, disease susceptibility and projected longevity of the tree. In fact, instead of earning money based on how much product you can spray on a tree, develop regular inspection protocols to identify problems as they arise. In this way, each inspection becomes a valuable tree service that can be invoiced. The invoice should be a combination set of notes from the current inspection, as well as problems that have the initial signs of becoming an issue. For example, the current inspection fee would be noted, followed by the observations of existing tree pests, such as tar spot, oak wilt or apple scab; the future problems section would include items such as the onset of decay or other developing problems.

Inspection is important not only for your client’s property, but also for specimens on neighboring landscapes, as well. If Sphaeropsis tip blight is evident next door, it would be wise to inform your client in a step to prevent damage to their trees. These observations should be placed in the future problems section of the invoice.

Tree inspection

Regular inspection and reporting will help to lower the liability of trees on a property. Photo: Sharon Skipton, UNL

Design programs according to need

If certain diseases are fairly common in your area, developing a ready-to-go treatment plan can be helpful. Based on the specific diseases to be dealt with, a half-dozen or so programs might be necessary. For example, if apple scab on crab apples is common, design a plan that many of your customers could use. Once the need has been established, application can proceed according to the prescribed schedule on the fungicide label. Individualized, customized programs may be necessary if the customer has unique specimens not commonly planted locally.

Tree health is the goal

Overall, keeping trees healthy is the goal. The idea is to keep them as a viable asset in the landscape, rather than a liability. Pruning, nutrient analysis and other procedures may be just as or even more important than fungicide application and should also be considered.