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Publication #SSORH7

Determining Problems on Woody Ornamentals Over the Telephone1

Zerba, Raymond H.2

BASIC DOCTRINE

  1. Ask most of your questions so that they cannot be answered by a yes or no.

  2. Form your initial opinion, if you must, but keep it to yourself and try to eliminate everything else first. Don't jump at the obvious!

  3. Don't be afraid to say you don't know, and don't feel that you have to apologize for not knowing.

  4. Never be absolutely positive in your diagnosis -tell the client what you think is the problem.

  5. If in doubt about any information, tell the client you will check on the control recommendation and call them back.

  6. When a third party might be involved or there is a chance for legal repercussions - Remember you are Government. Do the taxpayers or your county really want you to get in the middle of something that might turn into a lawsuit? If you think "yes" in this particular situation, give it to your agent. A visit will need to be made. Such cases cannot be handled over the phone.

  7. Use the plant diagnostic clinic whenever you have some doubt of what could be the problem.

  8. Don't worry about telling a person what they don't want to hear. Tell them what you think, and don't let them put words in your mouth!

  9. If someone says they read or heard that you do something a certain way and they are asking if you agree, answer with your honest thoughts. However, never disparage the person or article being quoted. This will immediately destroy your credibility. Instead say, "Perhaps that's the experience of that person, but I feel (or the University feels) this _______." Never belittle an authority! NOTE: Quoting the University or a specialist and crediting them with the information gives you immediate credibility.

  10. If you pick up on the fact a person seems happy with the way they are doing something, no matter how foolish or wrong it might seem to you, don't come out directly and tell them they are doing something wrong! Only an open mind will accept suggestions to change.

  11. Don't work with Commercial Clients (i.e., Pesticide Companies, Nurseries, Lawn Care Maintenance People, Farmers, Bee keepers, etc.). Let the agent handle their very special needs.

    1. Never make appointments for the Agent by saying: "I'll ask the agent to stop by and see you." or "The agent will return your call this afternoon" unless you know what you are saying is likely to happen. Let the office secretary make those statements.

BASIC INFORMATION TO ASK FOR

  1. What type plant is it? Possibly the most difficult question for a homeowner to answer but the basic one for you to start with.

    • PURPOSE OF QUESTION: Often it's guilt by association. We know that Junipers get Juniper Blight so if the interior of the plant is browning and the plant is being watered a lot ---- Juniper Blight? ---- maybe, but ask a few more questions first. Root Rot? ---- Construction decline?

  2. How long has the plant been planted?

    • PURPOSE OF QUESTION: If the plant is in the ground less that six months and having problems now, it is likely something is wrong with the way the plant was planted or its aftercare. This would suggest a whole new set of questions.

  3. How many other plants are showing the same symptoms?

    • PURPOSE OF QUESTION: A disease usually starts in one area and spreads out in an infection pattern. You don't see an entire Juniper planting dying all at once or every plant in a bed dying all at once. Diseases don't work that way. If many different plants are dying in the same area, it is unlikely you are dealing with a disease and need to start asking questions about watering techniques, chemicals or other cultural practices that might have been undertaken around these plants.

  4. What are the symptoms in the words of the person who you are trying to help?

    • PURPOSE OF QUESTION: Often people may have a "sneaky suspicion" of what the problem might be but hope it isn't so (especially of they think it might be something they did). Getting them to tell more about the condition in their own words sometimes gives you some clues to work with. Ask if the condition started on the older leaves or younger leaves. If on the older leaves, but restricted to the leaf edges, a foliar disease is not likely and you would once again need to ask more questions about watering, chemicals and other cultural practices. If on the other hand the condition is affecting the new leaves, have the client check carefully for insects or their evidence. It is my experience that most insects prefer to feed on growth that is less than three (3) months old. Diseases, on the other hand, while attacking new growth, don't often show up as a symptom until that growth has hardened off and is much older.

  5. How long has the condition been occurring and when did it start?

    • PURPOSE OF QUESTION: When people say their plant died overnight - try first to ask questions that would allow you to make up your mind as to whether it took longer but the person was just inattentive to the plant. If it did go from green to brown in less than a few days, then direct your question again to chemicals or cultural activities around the plant. No disease kills a plant in that short of a time. Often chemicals can kill in as little as seventy-two (72) hours and do cause a plant to go from green to brown with no yellowing stage in between.

INFORMATION ON CHEMICALS

To help you determine if they were involved with the decline, you might ask these questions.

  1. What have you fertilized with, when and how?

    • PURPOSE OF QUESTION: Some people use weed and feed products at the wrong time of the year and as a general practice most use them improperly. If used, how far did they stay out from shallow-rooted plants? Was there a lot of rain afterwards that could have floated the product down to the plants? Did they treat the whole area the same whether it had weeds or not or did they go over the weedy area a second time, thus over-applying the chemical? If they used straight fertilizer, was it the right time of year and were the plants under moisture stress at the time? Were the plants wet at the time of fertilizing? How close to the main stems did they come with the fertilizer?

  2. What other chemicals could have been applied around these plants?

    • PURPOSE OF QUESTION: Most people's perception of what can cause a problem is quite narrow. When answering these questions, many say "only an insecticide or fungicide by their lawn spray company." Except for the remote possibility of gross incompetence by the spray company's employee, these chemicals can be eliminated as a potential cause for a plant problem. Instead, ask about these additional items to expand the possibilities:

      • Have you cleaned your sidewalk with strong chemicals, such as Muriatic acid?

        • Have you cleaned the side of your house with TSP (trisodium phosphate)?

        • Where does your septic tank drain field run?

        • Where does the backwash from your pool or a neighbor's go?

        • Have you replaced the siding on your house or put on a new roof lately?

INFORMATION ON WATERING PRACTICES

To help you determine if watering is a problem, I would suggest asking the following questions.

  1. Do you have an irrigation system or water assisted heat pump?

    • PURPOSE OF QUESTION: If they do, next ask if they leave it on a timer or if it runs all the time. What's the time interval? I've seen some of these systems operating in the middle of a rainstorm!

  2. When do you water; how do you water?

    • PURPOSE OF QUESTION: This is to find out if they are watering by placing a hose near the plant or doing it properly. Also, this question will determine length of time that they water and how frequently, which can be a problem.

  3. Do you have dollarweeds growing in your yard?

    • PURPOSE OF QUESTION: I use the presence of dollarweeds as an indicator that the soil is one that stays wet for long periods or has an aeration problem.

  4. When you dig a hole during the rainy season, does it ever fill with water?

    • PURPOSE OF QUESTION: Gives you some background on depth of water table. If they answer "yes", then ask if they planted their plant lower than the surrounding grass or higher than it. In a wet site, it should set a few inches higher than the grass to allow for settling and mulching.

  5. Does water stand in the place where you have this plant?

    • PURPOSE OF QUESTION: Obvious.

    • An alternative question might be to ask if there is a lot of shade and does the ground stay mushy for longer periods whenever it rains?

    • PURPOSE OF QUESTION: People often have a slope to their ground and they respond when asked if their land ever stands water that "No, it is well drained". Question them further, however, and you may find out that they have a good run-off, but not good drainage (as a plant root would define it).

  6. Is the plant located near a roof without a gutter, sidewalk, or any other hard collection surface which traps water and dumps it onto the roots of this plant?

    • PURPOSE OF QUESTION: If it does, this plant could be receiving 600 or more inches of rain a year when a plant just ten feet away may be getting 60 or less. Collection surfaces can make a big difference to plant survival.

  7. Do you have black plastic under your mulch for excluding weeds?

    • PURPOSE OF QUESTION: While you can get away with this for a year or two, eventually the soil begins to turn to a poorly aerated one as algae and molds grow over the surface under the plastic impeding air and gas exchange.

INFORMATION ON OTHER PRACTICES

To add information if you still can't make a reasonable guess.

  1. Is the bark intact all the way to the ground with no sawdust or sap coming out?

    • PURPOSE OF QUESTION: If this question does nothing else, it causes the individual to look closely at their plant. If ants have built a nest near the base, they should be able to see to. If sawdust is coming out (unlikely in woody shrubs), borers should be suspected. If the bark is splitting away, the plant may have been planted too deeply or latent cold damage may be a problem depending on the plant species - Azaleas, Citrus, Pittosporum and Elaeagnus, to name a few, have been notorious for this in the past years in Florida.

  2. How far back do you keep the grass pulled away from the trunk?

    • PURPOSE OF QUESTION: While it is desirable to know if they are keeping competition down while the plant is small, the main point of this question is to find out how they are keeping the grass down around the plant if they are not pulling it out. String-trimmer type machines will girdle a trunk and people tend to ignore this damage even when told to look for it. Mowers can also do a job.

  3. Is the plant growing where Turkey Oaks once grew?

    • PURPOSE OF QUESTION: In North Florida, mushroom root rot is a common problem on old Turkey Oak land for seven (7) or more years after construction and the mushroom is not often present.

  4. Is there any swelling or sunken areas on the trunk?

    • PURPOSE OF QUESTION: These would indicate galls or cankers which could be due to insects or disease, depending on the host plant.

  5. If the plant has been in the ground for less than eight (8) weeks, did you use any Organic Peat or Peat Humus in the planting hole; and, if so, was it mixed well?

    • PURPOSE OF QUESTION: In North Florida, companies are selling peat muck under these names. While legal, it is an unfortunate practice, in my opinion. If the homeowner does not thoroughly mix it with whatever they are taking out of the planting hole, it will stay gummy when wet and as it dries it will crack apart. While you can never be sure of it, I suspect that some plants have been lost to this material as a result of its use in planting holes, especially in wet sites.

TIMES YOU PROBABLY CAN JUMP TO CONCLUSIONS

When they tell you the following:

  1. Something is eating the leaves off my plant!

    • RESPONSE: If you can be assured the leaves haven't fallen off the plant due to something else, then I think it is easy enough to recommend something for chewing insects. If the insect can be seen (and hit by a spray), I often recommend a contact insecticide. Depending on the height of the plant and type, have them check in the early morning hours for slugs. Flowering plants and vegetables when small often have this problem.

  2. The leaves of my plant have turned black!

    • RESPONSE: Talk with them about sooty mold, and piercing, sucking insects.

  3. Grey looking scaly growth occurring on the trunks and stems of my plants!

    • RESPONSE: Talk with them about lichens, but only if you have eliminated such things as Hypoxylon canker.

  4. White fluffy material on the stems of my plants!

    • RESPONSE: Depending on the plant, talk to them about Peach Scale and Snow Scale. If Roses or Crape Myrtle, discuss powdery mildew.

  5. Curly leaves on my plants out toward the ends!

    • RESPONSE: Talk with them about aphids and chemicals.

In closing, I am sure you could add to this list for many more pages, but at least this is a start toward and outline of how I handle diagnosis of plants problems over the phone. Hope it helps you.

Footnotes

1.

This document is SS-ORH-07, a series of the Environmental Horticulture Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. First published: May 1992. Reviewed: December 1993, August 2003 and March 2011.

2.

Raymond H. Zerba, Jr., Horticultural extension agent III, Clay County extension Service, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, 32611


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.