PLANT DETECTIVES Woody Plants

Directions Consider the information presented in each scenario – What is useful? – What is not useful? – What is missing? Based on the information provided determine a possible solution for the client Use an IPM approach for each of your answers

Goal Based on information provided by client, determine possible cause(s) and present range of solutions client can choose. – You are NOT telling the client what to do – You are educating the client on the control options available

What you need: N3959 or other access to publications

When you see these: After you have come up with your own answers, listen to our suggested reply to the client. Click on these icons when you see them in the presentation. – Must be connected to the internet

PLANT DETECTIVES Woody Plants

Scenario 1 Mr. Brown is very concerned about irregular spots on the leaves of his maple trees. He has called you on the Extension Garden Hotline and wants to know if he should cut down the tree immediately to prevent those blotches from spreading to his ash tree and roses.

Scenario 1 This spring has been very wet and humid. He tells you that he hasn’t seen any spots on his rose bushes yet, but last year most of the leaves fell off. His ash tree has spots, too. Mr. Brown wonders if that is Emerald Ash Borer.

Scenario 1 What is the most likely problem called? Using an IPM strategy, what information would you give Mr. Brown? Discuss these questions before continuing to answer on next slide

Scenario 1 Anthracnose – Irregular spots and dead areas on leaves that often follow the veins of the leaves Often tan or brown Often on lower portions of canopy Sometimes twig dieback Not many insects create spots on leaves. Many people, when they hear about new pests, attribute any new problems to those. Cutting down a tree is pretty extreme response – think first!

Scenario 1 Several diseases caused by different fungi specific to their own plants. Ash, maple, white oak, sycamore, and walnut are commonly affected. Typically affects young tissue. Primarily cosmetic. Anthracnose on silver maple Photo by University of Illinois

Scenario 1 Management options include: Tolerate, unless severe Sanitation Maintain tree vigor – water, fertilize appropriately Fungicides

Scenario 1 During the weekly Horticulture Update, Brian Hudelson often reports on common diseases. The week Mr. Brown called, Brian mentioned many samples of oak, ash, and maple leaves coming into the lab with spots that were diagnosed as anthracnose. Listening to this live program (or the archives) will alert you to current issues. ANTHRACNOSE is one of the few diseases you can diagnose own your own – most have to be sent to the lab for confirmation.

Scenario 2 Mrs. Oler has moved into a new house and has severely overgrown bushes and wonders what her options are to whip them back into shape? I have an overgrown shrub in my new yard. Please tell me how to prune it. Thanks in advance, Mrs. O.

Scenario 2 My neighbor says it’s a lilac bush and that the previous homeowner never pruned it. She s a picture of the offending shrubbery.

Scenario 2 Based on the information provided, what is your response to Mrs. Oler? Using an IPM strategy, what information would you give her? Discuss these questions before continuing to answer on next slide

Scenario 2 Management Options Include: Proper identification Expectations Pruning options – Cut back – Thin – Rejuvenate Future management recommendations

Scenario 2 Sharon Coneflower is out picking Japanese beetles off her roses, and looks up to see that most of the leaves on her birch tree look lacy and tattered. Panicked, she calls the Extension office to ask how she should kill the caterpillars she is SURE have eaten her birch tree’s foliage.

Scenario 2 When she can’t provide a description of the caterpillars she assumes ate the leaves, what other questions would you ask her? What is your best guess of what the culprit is? Using an IPM strategy, what options would you give Ms. Coneflower? Discuss these questions before continuing to answer on next slide

Scenario 2 Japanese beetle – If beetles are eating her roses, they are likely eating other favorite plants in the vicinity.

Scenario 2 Management options include: Tolerate, unless severe Maintain tree vigor – water, fertilize appropriately Systemic insecticide – Applied at correct time

Scenario 2 You discussed management options for Japanese beetle in the last session. How would your recommendations differ for this pest on a large birch tree as compared with roses?

Scenario 3 Mrs. Daisy Astor lost a magnolia last year to verticillium wilt (diagnosed by the UW Plant Disease Diagnostic Clinic). She now would like your advice for a new tree to put back into that spot.

Scenario 3 She wants something that will be a small to medium sized tree and has some ornamental qualities. The spot gets sunlight most of the day and drains well. What tree(s) would you suggest she consider? Discuss these questions before continuing to answer on next slide

Scenario 3 Consult appropriate resources – pdf (Choosing the Right Landscape Plants: factors to Consider) pdf – Choosing plants that are not susceptible to verticillium wilt is the most critical Finding what meets her aesthetic needs is secondary

Scenario 3 Vert resistant trees: – apple, aspen, azalea, beech, birch, butternut, crabapple, dogwood, flowering quince, ginkgo, hackberry, hawthorn, hickory, holly, honeylocust, katsura tree, mountain-ash, oak, pear, poplar, sweetgum, sycamore, walnut, and willow. Conifers are also resistant. Which ones meet her requirements? – Crabapples, pagoda dogwood, flowering quince, hawthorn, mountain-ash, ornamental pear, and possibly some small cultivars of katsura tree are all small to medium-sized and prefer full sun.

Scenario 4 Mr. Spector calls the UWEX office with concerns about the large tree on the north side of his home. It has large dead branches throughout the canopy. He knows emerald ash borer is a problem so wonders if his tree has it. He wants to know if should he cut the tree down.

Scenario 4 Do you have enough information to properly answer the question? What other information would you need? How should you direct Mr. Spector? Discuss these questions before continuing to answer on next slide

Scenario 4 Need more information – Bring in a branch to ID species (Choosing the Right Landscape Plants: factors to Consider) – Submit a picture of the symptoms and signs – Determine history of site – Possibly submit sample to Plant Disease Diagnostic Clinic – NEVER advise to remove a large tree – Recommend homeowner hire a certified arborist for complete inspection (Wisconsin Arborist Association)