Mealybugs are insects found in moist, warm climates. They are considered pests as they feed on plant juices of greenhouse plants, house plants and subtropical trees and also act as a vector for several plant diseases. Mealybugs tend to congregate in large numbers, forming white, cottony masses on plants. They feed on stems and leaves of fruit trees and ornamentals. High populations slow plant growth and cause premature leaf or fruit drop and twig dieback. Mealybugs can lower fruit quality by covering it with wax or sticky honeydew upon which black sooty mold grows. https://edis.ifas.ufl.edu/in993

Pink Hibiscus Mealybug – The pink hibiscus mealybug is a serious pest of many plants in tropical and subtropical regions. It was discovered in Broward County, Florida on 13 June, 2002, then in Dade County, and has continued to spread. This pest has two common names (pink mealybug and hibiscus mealybug), but there is an effort to standardize the common name by calling the pest “pink hibiscus mealybug,” even though it attacks many plant species, including citrus. http://entomology.ifas.ufl.edu/creatures/orn/mealybug/mealybug.htm

Scale Insects – Scale Insects vary dramatically in appearance; some are very small organisms (1–2 mm) that grow beneath wax covers (some shaped like oyster shells, others like mussel shells), to shiny pearl-like objects (about 5 mm), to creatures covered with mealy wax. Adult female scales are almost always immobile (aside from mealybugs) and permanently attached to the plant they have parasitized. They secrete a waxy coating for defense; this coating causes them to resemble reptilian scales or fish scales, hence their common name. Most scale insects are parasites of plants, feeding on sap drawn directly from the plant’s vascular system. Scale insects feed on a wide variety of plants.  https://edis.ifas.ufl.edu/ch195

Aphids – Aphids are minute pear-shaped, soft-bodied insects. Their reproductive potential, salivary secretions, and ability to transmit viral diseases make them the most potent and worldwide enemies of many crops and ornamental plants. There are approximately 4,400 aphid species in the world. Aphids suck sap from plants and cause the leaves to appear curled and distorted, especially when the population is high. They excrete honeydew, a sugar-rich substrate that promotes the growth of sooty mold. https://edis.ifas.ufl.edu/in761

Thrips – Thrips are are tiny insects that often go undetected but can cause serious problems in the garden. Both larval and adult thrips feed using a “punch and suck” technique. They can feed on leaves, buds, flowers, and even small fruit. Leaves infested with thrips dry out and have a stippled or silver-flecked appearance. You may see small brownish specks of excrement on the undersides of leaves. Infested flower buds fail to open, or the blooms are deformed, while damaged flowers become streaked and discolored. Chilli thrips feed on dozens of plants, including roses, citrus, plumbago, and Indian hawthorne. They attack all above-ground growth, but prefer young leaves, buds, and fruits. http://gardeningsolutions.ifas.ufl.edu/care/pests-and-diseases/pests/thrips.html

Spider Mite – The spider mite infests many different woody ornamental plants in the landscape, but is most commonly found on azalea, citrus, elaeagnus, plumeria and pyracantha. Spider mites feed on plant sap with needle-like piercing-sucking mouthparts, causing yellowing on leaves as the individual cells are collapsed, with continued feeding causing a ‘stippled-bleached’ effect initially along the midrib and major veins. As populations increase, distinctive webbing is produced on plant surfaces; if the mites are not controlled, leaf necrosis and defoliation will occur. Populations may be highest in spring and early summer and are often exacerbated by drought stress or the use of toxic insecticides that are disruptive to mite biological control

Rugose Spiraling Whitefly – Rugose Spiraling Whitefly A new addition on the list of whitefly species found in Florida, was originally called the gumbo limbo spiraling whitefly, but is now named the rugose spiraling whitefly. Being a fairly new species to science – identified less than a decade ago, not much information is available about this pest. It is an introduced pest, endemic to Central America, and was reported for the first time in Florida from Miami-Dade County in 2009. Since then it has become an escalating problem for homeowners, landscapers, businesses, and governmental officials throughout the central and southern coastal counties of Florida. Feeding by this pest not only causes stress to its host plant, but the excessive production of wax and honeydew creates an enormous nuisance in infested areas. The presence of honeydew results in the growth of fungi called sooty mold, which then turns everything in the vicinity covered with honeydew black with mold. https://edis.ifas.ufl.edu/in1015

Ficus Whitefly – There is a new pest attacking ficus trees and hedges in Miami-Dade, Broward and Palm Beach Counties, Florida. This pest was identified as the fig (ficus) whitefly, Singhiella simplex, and is a new US continental record. Whiteflies are small, winged insects that belong to the Order Hemiptera which also includes aphids, scales, mealybugs, and bugs. These insects typically feed on the underside of leaves with their “needle-like” mouthparts. Whiteflies can seriously injure host plants by sucking juices from them causing wilting, yellowing, stunting, leaf drop, or even death. miami-dade.ifas.ufl.edu

Cardin’s Whitefly – This whitefly has been known in Florida since 1917. Recent outbreaks seen on Duranta species. This whitefly is usually innocuous, but under some situations can become a damaging pest. These situations usually occur when something has disrupted the parasite/predator complex. https://edis.ifas.ufl.edu/in310

Powdery Mildew – Powdery mildew is a serious fungal disease that attacks a wide range of plants. The symptoms are unmistakable: spots or patches of white powder, usually on the leaves. Like all fungi, powdery mildew favors moist conditions and will thrive in humid weather, crowded plantings, and shade. Damage to infected plants can include the stunting of leaves, buds, and fruit. Leaves may yellow and drop and the plant will suffer as it loses nutrients to the fungus. Powdery mildew is more prevalent in spring and fall. gardeningsolutions.ifas.ufl.edu

Foliar Diseases – Foliar diseases are the most common among plant diseases. They appear as leaf spots and scars. The two types of foliar diseases are brown spot (caused by the fungus Septoria glycines) and frogeye leaf spot) caused by the fungus Cercospora sojina). Foliar pathogens are normally active with high amounts of moisture and prolonged leaf wetness. Irrigation early in the morning will help wash off leaf-bound dews filled with nutrients that encourage foliar fungal growth. Planting ornamental tropical plants in places where they can dry easily will help prevent foliar diseases. Watering earlier in the day will give enough time for the sun to dry the water. Avoid placing plants too close to water sprinklers to prevent foliar disease development. Ask a professional!

Ganoderma Butt Rot – Ganoderma butt rot is a lethal disease of palms, both in the landscape and natural settings. While the disease is more prevalent in the southern half of the state, where palms are in greatest abundance, it is certainly not restricted to that area. The fungus that causes the disease is distributed throughout Florida, from Key West to Jacksonville to Pennsacola. It is also known to occur in Georgia and South Carolina. http://edis.ifas.ufl.edu/pp100

Bud Rot of Palm – The most common bud rot pathogen in Florida is Phytophthora palmivora. Thielaviopsis paradoxa may cause this disease also. The first symptom is discoloration and wilting of the spear leaf and wilting/discoloration of the next youngest leaf. If severe, the spear leaf easily pulls from the bud. In palms with a canopy above eye level, this first symptom is often missed. Instead, a lack of new leaves and an open-topped crown are often the first symptoms to be observed. Because the bud is dead, no new leaves emerge. Older leaves remain healthy for months after the bud dies. Preventive fungicide applications are useful in a nursery situation for bud rot, but less so in a landscape with mature palms (palms with trunks). Bud rot is also observed in association with cold damage. Cold damage allows entry of secondary pathogens, both fungi and bacteria. http://edis.ifas.ufl.edu/pp144

Lethal Yellowing – Lethal yellowing (LY) is a palm disease prevalent in Florida landscapes in the southern one-third of the state. In 2007, the disease was observed in Sarasota and Manatee Counties on the west coast of Florida, counties where it had not been observed previously. In 2012, the disease was observed in Indian River County on the east coast of Florida. LY is also observed in field nurseries. This disease has significantly reduced the number of tall-type Cocos nucifera (coconut) in Florida and the Caribbean Basin, and localized outbreaks continue to occur. http://edis.ifas.ufl.edu/pp146

Texas Phoenix Palm Decline – Texas Phoenix palm decline (TPPD) is a new disease in Florida. This disease is caused by an unculturable bacterium that has no cell wall — a phytoplasma. The TPPD phytoplasma is similar to, but genetically distinct from the phytoplasma that causes lethal yellowing (LY) disease of palms. Texas Phoenix palm decline is a fatal, systemic disease that kills palms relatively quickly. The TPPD phytoplasma is spread naturally to palms by sap-feeding insects, such as planthoppers. Palms showing symptoms of more than 25 percent foliar discoloration or a dead spear leaf due to the disease should be removed immediately. As of June 2013, palm species known to be most severely affected by TPPD were Phoenix canariensis (Canary Island date palm), Phoenix dactylifera (edible date palm), Phoenix sylvestris (wild date palm) and Sabal palmetto (cabbage palm).  http://edis.ifas.ufl.edu/pp163

Graphiola Leaf Spot (False Smut) of Palm – This is a leaf spot disease of Phoenix species caused by the fungus Graphiola phoenicis. Disease looks similar to potassium (K) deficiency, but signs of fungus (i.e., the fungus itself) are obvious to naked eye. It is not a lethal disease, just unsightly. The Phoenix dactylifera cultivars Deglet Noor, Zahidi, Medjool are all susceptible – these are what we plant because these are the cultivars used for edible date production in the U.S. Phoenix palms are not adapted to sub-tropical Florida! Remove infected foliage. http://edis.ifas.ufl.edu/pp140

Leaf Spots and Leaf Blights of Palms – Leaf spots and leaf blights are caused by numerous fungal pathogens, but the symptoms they cause are relatively similar for all of them. All palms should be considered hosts for leaf spots and leaf blights, especially in the seedling and juvenile stages. Leaf spots initially start as small, water-soaked lesions that then turn various shades of yellow, gray, reddish-brown, brown, or black. These lesions are usually surrounded by a halo or ring of tissue that is a different color. Leaf spots can increase in number or size such that large portions of a leaf blade are diseased. Sanitation and water management are critical for leaf spot and blight disease management, especially in a nursery (both container and field). Injury prevention and good palm nutrition are part of the overall management strategy. Fungicides may be useful as part of an integrated management program. They should never be the sole component of a program. http://edis.ifas.ufl.edu/pp142

Fusarium Wilt Disease of Queen Palm and Mexican Fan Palm – Fusarium wilt is very host specific, with the primary hosts being Syagrus romanzoffiana (queen palm) and Washingtonia robusta (Mexican fan palm or Washington palm). It is caused by Fusarium oxysporum f. sp. palmarum. When this disease was first observed, it was referred to as “Fusarium decline.” However, now that the exact pathogen is known, the more correct disease name is “Fusarium wilt.” The full name of “Fusarium wilt of queen palm and Mexican fan palm” was given to this disease to distinguish it from the other Fusarium wilt disease that occurs on palm in Florida. There currently is no cure for this lethal disease. http://edis.ifas.ufl.edu/pp278

Fusarium Wilt Disease of Queen Palm and Mexican Fan Palm – Fusarium wilt is very host specific, with the primary hosts being Syagrus romanzoffiana (queen palm) and Washingtonia robusta (Mexican fan palm or Washington palm). It is caused by Fusarium oxysporum f. sp. palmarum. When this disease was first observed, it was referred to as “Fusarium decline.” However, now that the exact pathogen is known, the more correct disease name is “Fusarium wilt.” The full name of “Fusarium wilt of queen palm and Mexican fan palm” was given to this disease to distinguish it from the other Fusarium wilt disease that occurs on palm in Florida. There currently is no cure for this lethal disease. http://edis.ifas.ufl.edu/pp278

Fusarium Wilt Disease of Canary Date Palms – Unlike most fungal diseases of palms, this disease is very host specific, with the primary host being Phoenix canariensis (Canary Island date palm). It is caused by Fusarium oxysporum f. sp. canariensis. The name “Fusarium wilt of Canary Island date palm” was given to this disease to distinguish it from three other Fusarium wilt diseases that occur on palms. Fusarium wilt of Canary Island date palm was first documented in the United States in the 1970s in California, but it was not documented in Florida until 1994. It now occurs throughout the state.The fungus causes a vascular wilt. Specifically, it obstructs the xylem (water-conducting) tissue, which results in desiccation and death. There is no cure for this lethal disease. Fungicides have not been effective against Fusarium wilt. http://edis.ifas.ufl.edu/pp139

Palm-Leaf Skeletonizer – The palm-leaf skeletonizer is a moth, the larvae of which feed on many varieties of palms. As many as 78 species of palms are known to be hosts of this insect, which feeds only on palms. A study in 1995 showed that damage by this insect to coconut palms (Cocos nucifera) had been particularly severe. The caterpillars form dark tube-like structures on the underside of the leaf and eat leaf sections between veins. The resulting damage looks much like a leaf “skeleton.” http://okeechobee.ifas.ufl.edu/Skeletonizer.pdf

Normal “Abnormalities” in Palms – Consultants and extension agents are frequently approached by palm owners with concerns about the abnormal appearance of their palms. Most of these abnormalities turn out to be symptoms of a disease, insect, nutritional, or other physiological disorder. However, some of these “abnormalities” turn out to be perfectly normal for that particular palm species. Click on the link provided for some of these common “abnormalities” that cause concern among palm owners. http://edis.ifas.ufl.edu/ep344

Sudden Oak Death and Ramorum Blight – Sudden oak death and ramorum blight are emerging diseases capable of causing a range of symptoms, from leaf spots to plant death, on many woody hosts. Because these diseases are emerging, much about the pathogen, host range, and disease epidemiology is currently being researched. The pathogen was introduced into the state through ornamental plant commerce, but eradication efforts have reduced the pathogen to below detectable levels. Only the foliar dieback disease ramorum blight has occurred in Florida in the past; no oak trees have died in Florida from sudden oak death. Currently, neither sudden oak death nor ramorum blight is established in Florida, but state agencies and university educators continue to work together to monitor for these diseases. http://edis.ifas.ufl.edu/pp118

Sphaeropsis Gall of Holly and Other Landscape Ornamental Plants Common in our area is a fungal infection called Sphaeropsis tumefuciens (aka Witchs’ Broom), which can affect many varieties of trees and shrubs such as oleander, bottlebrush, citrus, crape myrtle, wax myrtle, ligustrum, and even the invasive Brazilian pepper tree. This disease may also be present as a knotty gall rather than the witch’s broom effect. Our Florida hollies have been badly affected by this disease, also called stem gall, which is usually fatal. Since no effective fungicides are available, the best treatment is to prune the branch back to at least six inches below the affected area. Examine the cut end of the stem and remove more if discoloration is present.

http://palmersgarden.blogspot.com/2009/05/holly-witches-broom-gall.html