WHITEFLIES A-SPIRALIN!

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1 NEWSLETTER SEPTEMBER 2018 WHITEFLIES A-SPIRALIN! The Rugose Spiraling Whitely (Aleurodicus rugioperculatus), or RSW, made its debut in the U.S. in 2009, wreaking havoc on Gumbo Limbo trees in Miami-Dade County. After its arrival, this invasive pest, thought to originate in Central America, quickly increased its appetite to include over 100 other ornamental plant species, most notably coconut palms, Christmas palms and white bird of paradise. The pest rarely kills mature, healthy trees, however heavy infestations can be detrimental to smaller or unhealthy plants. Spiraling whitefly residue on palms and bird of paradise. Photo credit Vivek Kumar, UF. Adult spiraling whitefly. Photo credit H. Glenn, Spiraling egg pattern on the bottom of a Gumbo Limbo leaf. Photo credit S. Parker. Signs of RSW The most obvious sign of infestation is a buildup of a white waxy material covering leaves and fronds, which serves as a protective mechanism for eggs and nymphs. A closer look will reveal the namesake characteristic, circular spiraling egg patterns on lower sides of leaves. Continued on page 2. Hurricane Preparedness (pg. 3) More In This Issue Fall dry season and plant response Hurricane Preparedness Managing Urban Trees for Wind Endurance Team Member Spotlight Plant of the Month 1

2 SPIRALING WHITEFLY cont d from page 1 Damage and Nuisance Adult whiteflies congregate on the undersides of leaves to feed and reproduce, says Dr. Catherine Mannion from UF in her August 2010 publication, Rugose Spiraling Whitefly ( 20whitefly.pdf). Like other whiteflies, the insects siphon plant sap, which is excreted as honeydew after their bodies absorb the nutrients they need. This sugary, sticky substance attracts ants and encourages the growth of black sooty mold on understory plants and anything else underneath infested trees. If enough feeding occurs plants will be unthrifty and/or lose leaves. Remembering a trip to the Village of Key Biscayne with a colleague Arborist to collaborate with UF and the City s pest control on treatment strategies, Dr. Stephanie Parker (Mainscape s Regional Director of Agronomy) recalls, It was incredibly messy. Honeydew was getting all over peoples cars, homes and patio furniture. To make matter worse, tiny hair-like waxy filaments were flying in the wind, landing everywhere. Residents were pushing to have all the Gumbo Limbo trees removed. Fortunately effective treatments were put in place and this didn t happen. Sooty mold is a black, flaky growth on plant leaves, stems and trunks that is often confused for some sort of plant disease. Instead of being the cause of a plant problem, it is a sign that insects have been feeding specifically, those of the piercing-sucking variety named so because of their specialized mouthparts like tiny needles that extract plant sap. Understory plants and patio furniture covered in sooty mold. Management of Rugose Spiraling Whitefly Car covered in waxy filaments and honeydew produced by RSW. Biological control is a key element in management of RSW. According to Florida Department of Agriculture & Consumer Services RSW populations declined within a couple years after arriving due to increased numbers of a parasitic wasp and predatory beetles feeding on them in nature. The population dynamic between natural predators and the pests they feed upon is typically ebb and flow. We have seen a recent resurgence of RSW most commonly on coconut palms. The infestation is not nearly as severe as in the beginning, however it is heavy enough in some locations to warrant treatment. Trunk injection with a systemic product provides excellent control lasting up to a year. Mainscape personnel will be on the lookout for RSW on each property we maintain and provide proposals for treatment of palms and trees as needed. If a RSW infestation is suspected, please contact Customer Service at or What goes in must come out! The sugary excrement of these insects is a perfect substrate for growth of the black sooty mold. Other insects in this category also associated with sooty mold are aphids, scale insects and mealybugs. After insects are treated sooty mold will remain on plant leaves until it eventually washes off. Spraying with soapy water and using a strong hose stream to rinse is one way to remove sooty mold. Fungicides are not effective or necessary. 2

3 Turf performance in the landscape during summer/fall transition Preparing in advance is key to remaining safe in a hurricane! Here are some precautionary steps to take now to help you prepare for this hurricane season: Evacuation Planning - If you live in a hurricane evacuation zone, review local government information on evacuation shelters and plans. Test the route in good weather beforehand. Buy supplies in advance - Avoid waiting in long lines for limited goods. Check insurance coverage - Make sure your home is protected against flooding and wind damage. Move car into a garage or off-site location Documentation - Make copies of important documents and take photos of valuables inside the home. Hurricane Kit essentials: First aid kit Battery-powered or handcrank radio Flashlights and batteries Whistle to signal for help Local maps As usual for Florida, summertime came with an abundance of rainfall a welcome reprieve after the spring dry season. There s no doubt that frequent rain keeps grass green and growing, but several months of heavy rainfall can have effects on lawns that will soon be evident in the warm, dry conditions of early fall. As a general rule, deep and infrequent watering is the best way to promote healthy turf that can better withstand periods of drought. Indeed, allowing soil to dry until plants reach a point of moderate drought stress, then watering to wet the entire root zone again stimulates more roots to grow deeper, which is the key to stress tolerance. Daily summer rains, however do not allow this to happen because the upper soil profile is always at field capacity (maximum water holding potential). In this case the plant doesn t need to grow deeper roots to satisfy the plant water requirement. In fact, root depth tends to decreases making turf dependent on frequent watering to perform its best. Heavy soils that hold a lot of moisture and areas that do not drain well due to an underlying hardpan or high seasonal water table may stay saturated for prolonged periods during the rainy season, limiting the amount of oxygen that roots need to survive. Fine roots and microscopic root hairs functioning to take up much of the water and nutrients needed by plants are the most vulnerable and first to deteriorate. As cells collapse and roots become thin and weak, turf may decline from secondary soil-borne disease such as Pythium and Take-all root rot. In early fall when conditions become drier and temperatures are still hot turf typically goes through a period of stress because it has essentially been spoiled and needs time to adjust (grow deeper roots) to the increased water requirement. This is difficult to avoid, especially where watering restrictions limit irrigation frequency to two days per week. During this seasonal transition period it is common to see turf take on a bluish-grey appearance with folded leaf blades or turn brown in some areas in as little as one to two days without rainfall or irrigation. Though this may be alarming, it does not mean the turf is dying. In most cases these effects are temporary and turf undergoes a fully recover as new roots are formed. Backup portable chargers for cell phones 3

4 Managing Urban Trees for Wind Endurance Trees are the most valuable asset in the landscape and the hardest to replace if they fail during a storm. They also have the highest potential to cause damage if they fall on homes, cars and powerlines, yet the proper care of them is often overlooked either because of a lack of knowledge or the cost of pruning for wind resistance. Mature trees that fail often do so at the union of two or more trunks of equal size, or co-dominant stems as shown in the photo to the right. If there is a visible line or seam extending below the point where co-dominant stems meet as illustrated in the photo (right) above, this is a sign that the union is weak and consideration should be given as to what may be harmed in the event it should split as shown in the photo (left) above, which could occur even on a perfectly clear and calm day. It can be difficult or impossible to correct mature trees with large codominant stems, however there are bracing techniques that can reduce the risk of failure. If codominant trunk positioning poses a potential risk to people or property in the event of the tree splitting at the stem union, consider consulting a tree company to discuss bracing options if the tree is of value. Trees pruning specifications matter!!! Tree trimming should be more than just raising and thinning Young trees should be pruned to eliminate codominant stems and achieve a stable structure with a single trunk. This type of structural pruning requires planning and typically occurs over several years. It is often overlooked, however it is important to consider for the long term performance and safety of trees in a community setting. Tree trimming without well-articulated specifications is like setting sail in uncharted waters without a compass. Here are some tips to ensure quality work and met objectives: Consult with a Certified Arborist to help clearly define the long and short term goals of your tree trimming program. For more information contact us at or www. Mainscape.com Have a Certified Arborist help write tree trimming specifications and review them each time tree trimming is done. Be sure the pruning objectives are clearly defined in the specs and reviewed with prospective contractors before getting bids for the work. Verbiage matters specs should use terminology consistent with ANSI A-300 Standards and BMPs for Tree Pruning and require contractors to follow these standards. Specs should require that all OSHA and ANSI A300 Standards for safety are followed. Be sure contractors are licensed and insured and trained to meet the specific pruning objectives. Pruning for good structure is technical and requires talent! Consider having a certified arborist manage tree trimming for quality assurance. 4

5 TEAM MEMBER SPOTLIGHT Jose Torres Position: Operations Field Manager Naples North Time with Mainscape: 6 years This month we would like to spotlight Jose Torres, Operations Field Manager at our Naples North service center. Jose s leadership potential was noticed early on as he effectively worked with crews mowing, pruning and performing bed care operations. He would offer up advice on how to maximize quality production, perform work safely and teach team members how to work smart. Sal Femia, Jose s direct Supervisor has this to say about Jose: I have sent Jose and his team to work with many different Branch managers and each time I ve been told that the amount of work he gets done in a day is exceeds expectations. He is committed, willing to jump in and help, and such a valued team member. When asked what he likes about working with Mainscape, Jose says he enjoys that Mainscape has a People First culture, listening to its employees and incorporating good feedback, and the family atmosphere. Jose lives in SW Florida with his wife and 4 children 2 boys and 2 girls! He enjoys fishing and motorcycles. We are happy to have Jose as part of the Mainscape family and look forward to his continued leadership development working towards a bright future! 5

6 Plant Profile Japanese Blueberry Elaeocarpus decipiens Contact Us Contact us to learn more about our services Japanese blueberry is a beautiful low-maintenance, evergreen accent tree that grows dense, lush, dark green foliage all the way to the ground and is known for its extreme versatility and high performance in the urban landscape. This species reaches 10 to 12 feet tall in the first couple years after planting, then growth slows. Specimens are commonly manicured into a formal oval or conical shape at this size, planted as accents in plantings close to the home. They make a great substitute for similarly shaped plants that have not performed well due to disease, wet feet or other challenging soil conditions. Japanese blueberry can also be used in a tall hedge for privacy screening or limbed up and allowed to grow into small trees, easily maintained at 20 or 30 feet tall. The elliptical shaped leaves provide textural interest, each one blazing into bright red just before it drops. Ask us about the benefits of Soil Core Aeration! We are in the relationship business High Quality Landscaping Award-winning Services Outstanding Staff 2018 Mainscape Authored and Edited by Dr. Stephanie Parker, Regional Director of Agronomy, Mainscape Every effort is made to provide accurate and complete information in Mainscape newsletters. Mainscape makes no claims, promises or guarantees about the accuracy, completeness or adequacy of the contents of its newsletters and expressly disclaims liability for errors and omissions in the contents therein. Neither Mainscape or any of its employees assume any legal liability for any direct, indirect or any other loss or damage of any kind for the accuracy, completeness, or usefulness of information disclosed. 6