Backyard Gardener I N T H I S ISSUE Controlling Turfgrass Diseases...Page 1 A Typical Day in the Garden Page 3 From the Plant Clinic...Page 4 Air Potato Vine...Page 5 Calendar of Public Events Page 5 Become a Florida Water Star Flyer...Page 6 U F / I F A S E X T E N S I O N, V O L U S I A C O U N T Y Controlling Turfgrass Diseases Joe Sewards UF/IFAS Extension Volusia County Urban Horticulture Agent and Master Gardener Coordinator This has been a tough year for many lawns in Volusia County. The number one concern of people who come to our Master Gardener Plant Clinics is turfgrass. With the inordinate amount of rain that we have received this summer, many lawns have been affected by one, or more, turfgrass diseases. Turf diseases are sometimes difficult to diagnose; especially if one is not familiar with their life cycles and the conditions necessary for them to become problems. It is necessary to understand that most turf disease organisms are ubiquitous in the environment and, that they require a favorable environment in which to become problems for homeowners. Figure 1 It is not unlike diseases that affect humans. Many disease organisms surround us 24/7 and, because we are relatively healthy, we are able to ward them off with our body s natural defenses. When we become stressed for some reason, then we are susceptible to infection. The same is true of turf. If it is subjected to some environmental stress then it is more likely to become affected by some pathogen. The key then, is to maintain turf health and to not create an environment that favors development of the pathogen(s). Rule Out Other Factors First An injury to turfgrass is a destructive physical occurrence, such as pesticide damage (Figure 1), mowing the grass too short (Figure 2), or a fuel leak. Again, while these problems may appear to be diseases, there are no pathogens involved. However, these injuries or disorders may weaken the turf so much that a pathogen may attack the plants and cause a disease. Again, these are examples of stresses that can lead to disease. Turfgrass Disease Cycles Turfgrass diseases in Florida are caused by fungi (molds in a bathroom Continued on Page 2 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. U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A&M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. 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. U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A&M University Cooperative Extension Program, and Boards of County Commissioners Cooperating.
Figure 2 Continued from Page 1 orange or old bread are fungi). Most fungi living in lawns are totally harmless to plants. In fact, they are beneficial because they decompose the grass clippings and old roots. A very small number of fungi cause plant diseases. It is important to know that when a fungal pathogen is not actively attacking the plant, it has not disappeared from the turfgrass area. It is simply surviving in the environment in a state of dormancy (like a bear in hibernation) or as a saprophyte (nonpathogenic phase), living off dead organic materials in the thatch and soil layers. Disease Symptoms Try to determine if the active disease sites are associated with environmental characteristics, such as excessive shade, fertilizer application timing, type of fertilizer, soil type, or excessive irrigation. Use these records to help predict disease outbreaks and to design effective management strategies. There are two common patterns of turfgrass disease symptoms. One is a circular patch of turfgrass, either small or large, that is no longer uniformly green. The second is turf that has spots on the leaves. If disease patches are present, examine the leaves and roots in these patches for characteristic disease symptoms and signs (actual fungal structures) of the pathogen. Monitoring the weather helps with disease prediction and with determining the necessity of fungicide applications. If the diseaseaffected areas are small and the weather is not conducive to an epidemic, then a fungicide may not be necessary, or only spot applications may be required. However, if the longterm weather forecast is conducive to development of a disease that routinely occurs in the area in specific landscapes, then a fungicide may be useful in preventing an outbreak. 2 Disease Control Is Not Simple, Inexpensive or Easy! Disease control recommendations are aimed at (1) altering the environment so it is less favorable for disease development, (2) suppressing pathogen growth, and (3) decreasing stress on turfgrass. An integrated management program that includes cultural and chemical methods is the key to preventing and controlling turfgrass diseases. The key to this is to remember the pest/ plant relationship triangle. In order for any pest to become a problem (this can apply to insects and weeds as well) three things MUST be present; the pest, a susceptible host and an environment that favors development of the pest. If you take away ANY one of the three criteria, then infection cannot occur. For example, if you are continually battling large patch fungus (Rhizoctonia solani, which can affect all common lawn species in Florida), you first must understand its life cycle. It is active during cooler weather (from about mid-september to mid April). It is also more prevalent in areas that are over-watered, where it is somewhat shady and if the turf has been fertilized with a lot of nitrogen, particularly when it is cool. These are examples of an environment favoring disease development. If you change the environment, the disease will be reduced if not eliminated. This would mean cutting back on water and fertilizer during cooler months, and perhaps reducing the shade. Another option would be to spray fungicides Large Patch Fungus problem. but, as long as the conditions favoring disease development remain, the fungus will continue to be a In many ways, applying pesticides (in this case a fungicide) is merely treating a symptom. Diseases are problems in and of themselves but, they are also symptomatic of growing conditions that favor disease and not plant (turf) growth. Changing the conditions to favor Continued on Page 3
Continued from Page 2 turf development is, in the long run, a less expensive and more sustainable solution. Besides, most modern fungicides that are labeled for turf are expensive to apply. 386-822-5778. You can e -mail them at: mastergardener@volusia.org. You can also visit the University of Florida Electronic Document Information Service (EDIS) at: http://edis.ifas.ufl.edu. Cultural Practices are the Key! Be sure that you follow UF/IFAS recommendations for watering, mowing and fertilizing. Keeping the lawn healthy is the single best way to keep diseases minimized. If you do apply fungicides, be sure you are using those that are labeled for turf and that are also labeled for the particular disease you have. READ THE LABEL! The label is the law. If you have trouble understanding the label or aren t sure what product you should use, call the UF/IFAS Extension, Volusia County Master Gardener Clinic. We can help you sort things out. The phone number is Controlling turf diseases is not easy. You must understand the nature of the disease, why it is a problem and perhaps change the way you are caring for your lawn in order to deal with it effectively. Cultural practices include selecting the proper turfgrass, mowing at the correct height, irrigating only as needed and at the correct time, balancing nitrogen and potassium in quantity and source, avoiding or reducing excessive thatch accumulation, and preventing or reducing compacted soils. These cultural practices will help save not only your lawn, it will save you time, effort and money! Master Gardener Vision Statement To be the most trusted resource for horticultural education in Florida Master Gardener Program Mission Statement To assist extension agents in providing research based horticultural education to Florida residents. A Typical Day in the Garden for an ADD MG Gardener Submitted by Rich Cherry Always begins the about the same way. A simple "must do" list from the night before (Often as you will see, the SAME list as the day before!) Starts with an encouraging walk out the front door. Plan to check out the white water fountain...continues to trip the GFI circuit. (Mosquito breeder!) Quickly notice that weeds have begun to "blossom" in the herb garden pots by the front entrance. Ok, just a few minutes on this. Not a problem. About 60 minutes later...oh, I'll never get this finished! The heat is whipping me down. Need to get to that water fountain. On the way, notice fire ant hills thriving in the grass. Fortunately, I have fire ant killer in a shaker can in the garage. (15 minutes search locating shaker can) Notice that irrigation tubing in garage is all tangled up. Simple project here...just wrap and store (requires moving several boxes, other hoses...45 minutes.) Shaker can is almost empty...find Fire Ant Killer in aluminum bag. When searching, find liquid "permanent green stain" fertilizer and remember that herbs have not been fertilized for a long time. Now to find the hose-end sprayer. (20 minutes later.) Starting to cloud up, wondering if it will be a waste to fertilize today. Write it instead on tomorrow's "Must Do" list. Let's see...what was I going to do out here today? And so it goes... 3
From the Plant Clinic We Get Calls Submitted by Jean Porter Right Plant, Right Place Q: I planted a coontie and now it is getting larger than I thought it would A: A coontie will mature to 1 3' tall and maybe more. Recommended reading; University of Florida Web site: www.solutionsforyourlife.com, and search Florida Coontie bulletin ENH 117. Broken or dead leaves can be pruned 1/4 above ground level. Avoid removing healthy green leaves as much as possible to prevent damaging the coontie palm's health. You may consider moving this coontie to a different location where it can reach its ultimate growth. Hawk Doesn't Like The Taste: I was watching a hawk fly over with something green and red in its mouth. I thought it was a bird or a snake. The hawk didn't get very far when he dropped it. In checking it out, I was astonished to see that it was one of my wife's gardening gloves. She had put it on the top of a fence to dry. Guess it didn't taste very good. Magnolia Takes It Time: Q: My magnolia is 4 years old. It had a few blooms last year, but none this year. The leaves are healthy and the tree has grown to 15' tall. A: Most magnolia trees bloom at 10-15 years of age and a few cultivars may bloom earlier. Any blooms before that are a plus to enjoy. Asian Scale: Q: There is a white substance all over my Sago Palm A: Your sago palm is probably experiencing an infestation of Asian Aulacaspis Scale. Coffee seems to control Asian Aulacas[is Scale. Spray the fronds top and bottom with the coffee and scatter the grounds on the ground under the tree. The coffee liquor will control the scale already on the leaves and the coffee grounds under the tree will prevent the new larva from climbing up the trunk. Also, we have found that the most consistently effective treatment for controlling the cycad aulacaspis scale insect has been spraying them with oils. We have been using fish oil emulsion, but one of our colleagues has been using a petroleum-based horticultural oil with good results. We mix the fish oil with water at a rate of 1 part oil to 100 parts of water. Love My Fig: Q: My fig tree was looking and growing great. Then it started getting brown spots and the leaves fell off. A: Your fig tree apparently has fig rust on the leaves. To control fig rust, spray your fig leaves with Bordeau Mix or copper sulfate and lime following directions on the container. Look for a rust free summer and figs in the fall. 4
Air Potato Vine Dioscorea Bulbifera Submitted by Marlene Druschel I live in a HOA in Daytona Beach. I was taking a walk when I noticed this huge vine on a neighbor s tree. Since I am from western Pennsylvania, I thought it was Kudzu, because I have heard so much about that invasive vine. I contacted Joe Sewards at the Volusia County Agricultural Center and he told me to send pictures of the vine, which I did. He responded that it was air potato vine and he suggested that i go on the University of Florida IFAS web site and search for brochure #EENY-547, http://edis.ifas.ufl.edu/in972. It has a wealth of information about potato vine and I discovered that I could order the air potato leaf feeding beetle if needed. I went back to my original site and discovered that the beetles were present and happily eating away. I submitted photos of the vine along with GPS coordinates and sent the info to Paul Pratt at the USDA. He and his team are monitoring locations where the beetle is present. Now, I am checking out my entire HOA, including the golf course and am submitting my findings to Paul. I hope this information is helpful to you. If you are interested in obtaining some air potato leaf beetles, there is currently a waiting list but, they are available, for free. You can find out more about the air potato leaf beetle and find the form with which to order them at: http://bcrcl.ifas.ufl.edu/airpotatobiologicalcontrol.shtml. Calendar of Public Events Topic Date Location Welcome to Florida We Garden Differently September 4, 1-2:30 pm DeBary Hall (1.5 CEUs) Ormond Beach Library Plant Clinic September 8, 10 am 12 n Ormond Beach Library Vegetable Gardening September 13, 10 11:30 am DeBary Hall (1.5 CEUs) Master Gardener Plant Clinic September 16, 1-2 pm New Smyrna Beach Library Sugar Mill Garden Q & A and Workday September 17, 9-11 am Sugar Mill Garden, Port Orange Strawberries at Home and Strawberry Plant Sale September 20, 10am 12 n Ag Center Deland $5.00 FNGLA Landscape Show September 25-27, 8am 5 pm Orange County Convention Ctr. For more details Master Gardeners should check the VMS calendar. The general public may contact the Volusia County Agricultural Center. Volusia County Agricultural Center 3100 E. New York Ave. (S.R. 44), Deland, FL 32724 At the Volusia County Fair Grounds West Volusia 386-822-5778 Daytona Beach 386-257-6012 New Smyrna Beach 386-423-3368 Like Us On Facebook www.facebook.com/universityoffloridaifasvolusiacountyextension 5
6 Master Gardeners can attend the training for CEUs and would not need to take the exam since they would not be seeking certification.