by Gary Knox | Mar 31, 2015
![Figure 1 Note the black sooty mold coating the layers of white and grey scale, believed to be crapemyrtle bark scale, Eriococcus lagerstroemiae. [Photo by Gary Knox]](https://nwdistrict.ifas.ufl.edu/hort/files/2015/03/crapemyrtlescalebark1.jpg)
Figure 1 Note the black sooty mold coating the layers of white and grey scale, believed to be crapemyrtle bark scale, Eriococcus lagerstroemiae. [Photo by Gary Knox]
Symptoms and Appearance
An early symptom of crapemyrtle bark scale is black sooty mold covering extensive areas of leaves and stems as a result of honeydew exuded by the scale (Fig. 1). Individual scale insects are white to gray in color and ooze pink when crushed (Fig. 2). Large populations build up in branch crotches and extend up branches, appearing crusty white to gray. This scale usually is not present on new growth, leaves or slender stems unless infestations are heavy.
For more information and additional photos
Resources, up-to-date information and additional photos about crapemyrtle bark scale may be found at http://www.eddmaps.org/cmbs/. This website will be the major portal for information about this pest.
Figure 2. This white to grey colored scale oozes pink when crushed. [Photo by Gary Knox]
Research
Research on crapemyrtle bark scale is ongoing. Scientists from the University of Florida, LSU, University of Arkansas and Texas A&M are collaborating to develop Best Management Practices to manage crapemyrtle bark scale in the nursery and landscape. Initial research is examining the biology of the host-insect interaction to better understand its life cycle and stages when it may be most susceptible for control. Additional research will evaluate pesticides and other IPM strategies for managing this pest.
The expanding distribution of this scale and my personal observations of crapemyrtle bark scale throughout China suggest this scale could have a widespread and severe impact on crapemyrtles in landscapes. Please be on the lookout for crapemyrtle bark scale, and report sightings to your local county extension agent and Florida Department of Agriculture and Consumer Services Division of Plant Industry.
by Taylor Vandiver | Mar 24, 2015
It’s that time of year again, that time when your car changes color like a chameleon in order to mimic the surrounding landscape. Anything that stands still long enough will become coated with a light green to yellow dust. What is this dust you might ask? What you are seeing is pollen, a sure sign that spring has arrived and allergy season is here! The pollen that can be seen is from pine trees and is not a major contributor to allergies, but the invisible pollen from oak trees and other plants can wreak havoc on sinuses. And while you may be cursing the trees for causing your eyes to water and coating your car, it’s important to remember that plants need pollen in order to reproduce.
Pollen disseminating from a pine tree anther. Picture courtesy of http://supermanherbs.com/megadose-pine-pollen/
Pollen is disseminated from blooming trees and plants. The process of pollination develops new plant seeds. Pollen is dry and light, enabling it to float through the wind and travel several miles. Plants that depend on wind for dispersal have to produce massive amounts of pollen since only a small amount will actually result in seed production. Plants pollinated by insects don’t have to produce as much pollen because of the efficiency of the insects in distributing the pollen. Changes in the weather directly influence the amount of pollen and how it will affect allergy sufferers. Rain dampens pollen and reduces its ability to flow through the air. A freeze can also slow down a tree’s rate of producing pollen. Windy and warm weather can increase pollen amounts.
A Leon County allergy and asthma specialist stated that roughly 40 percent of the population suffers from pollen allergies. The best thing you can do if you are part of this 40 percent is to reduce your exposure to pollen. Here are a few ways you can keep your allergies at bay:
- Dry clothes in an automatic dryer rather than hanging them outside to avoid pollen collecting on clothing and being carried indoors.
- Consider limiting outdoor activities during the pollen season (Florida trees often release pollen from January to June).
- Stay inside during peak pollen times (from 10 a.m. to 4 p.m.).
- Restrict outdoor activities during days with high winds and low humidity.
- Shower after spending time outdoors to remove pollen from hair and skin.
- Use air filters and clean regularly, or run an air conditioner and change the air filter frequently.
- Wear a dust mask when mowing the lawn, gardening, or raking leaves.
If you would like to know what trees are producing pollen in your area at certain times of the year you can visit this website http://www.pollenlibrary.com/State/Florida/. As always, feel free to contact your local Extension Office for more information.
by Mary Salinas | Mar 2, 2015
The sight and sound of birds in the yard reconnects us to the wonder and beauty of nature. Providing food, water and shelter can bring the joy of our feathered friends into outdoor spaces.
Leave behind the standard palette of trees and shrubs that characterize many urban landscapes. Rather, choose trees and shrubs that provide food and shelter to birds. Here are just a few to consider:
Hawthorns – The thorniness of these trees provide excellent protection for birds nesting in their strong branches. In spring, their abundance of blooms attracts a wide variety of pollinators. The size of the fruits vary with different species of hawthorn. For instance, the yellow haw (Crataegus flava) has large fruit suitable for larger birds, while the littlehip hawthorn (C. spathulata) produces small fruit for even the smallest of the fruit-eating birds.
Hollies – When most other fruiting trees are bare of fruit in winter, hollies provide abundant berries in the fall and hold them well into winter to provide food for migratory and resident songbirds. Dahoon holly is a versatile tree for many landscape settings, from dry, sunny locations to moist woodlands. It is even moderately salt tolerant.
Viburnums – This family of large shrubs are adaptable to a wide range of landscape situations. The dense foliage and branching provide excellent nesting opportunities for birds. Flowers bloom in spring to summer and are followed by purple fruits in late summer and fall that are enjoyed by many birds.
Songbird at a tube feeder. Photo by Thomas Wright, UF/IFAS.
Do you want to attract birds right away? While you wait for new plantings to mature and provide food, put out a few bird feeders. There are a wide variety from which to choose. Tube, hopper and platform feeders can be filled with a variety of seed mixes. Suet feeders are constructed of a heavy gauge wire and hold a solid cake of animal fat with seeds, nuts, grains or fruits. Nectar feeders cater to hummingbirds. Fruit feeders are made to hold large pieces of fruit, like apples and oranges. The type of feeder and food you offer will determine the species or type of birds you will attract.
Don’t forget a bird bath. Birds need a clean water source, so remember to rinse it on a regular basis.
Think twice about attracting birds, though, if you let your cats run free. Cats are dangerous to our bird populations. But if they are strictly housecats, they will love to watch the birds through the windows or porch screens as much or even more than you will.
For more information:
U.S. Fish & Wildlife Service: Backyard Bird Feeding
Attracting Backyard Birds: Bird Feeder Selection
by Gary Knox | Feb 24, 2015
‘Jon Jon’ magnolia
This winter’s recurring freezes and frosts have played havoc with early flowering plants like magnolia. While buds are freeze-resistant, open magnolia flowers can quickly turn brown after exposure to temperatures about 30°F or lower. One way to avoid freeze-damaged flowers is to choose later blooming cultivars. These selections have flowers that open in north Florida during late February or later.
The Magnolia Garden at the University of Florida/IFAS North Florida Research and Education Center (NFREC) in Quincy has more than 150 types of magnolias planted. Based on over 10 years of data, five of the latest blooming magnolias are Daybreak, Jane, Betty, Jon Jon and Ann. These cultivars have peak bloom dates ranging from late February (Ann) to mid-March (Daybreak). Thus, they bloom after most flower-damaging freezes.
Daybreak has beautiful, large shell-pink flowers on a small tree. Jon Jon has huge white flowers with a streak of red-purple at the base. These fragrant flowers open goblet-shaped the first day, and then open wider to a cup-and-saucer shape on subsequent days. At NFREC, Daybreak and Jon Jon have about 6 weeks of flowers and grow as single-stem or multi-stem trees up to about 30 feet tall.
Jane, Betty and Ann are sister cultivars developed at the National Arboretum. As you would expect with sisters, they look-alike, and have a shrubby or multi-stemmed tree habit, generally growing about 15 feet tall and wide (much shorter and wider than Daybreak and Jon Jon). All three have upright, cup-shaped flowers in various shades of pink and red-purple. Betty has medium red-purple flowers that are the largest of the three, over 4 inches. Jane has 3- to 4-inch flowers that are medium pink outside and white or pale pink inside. Ann has the smallest flowers (3 inches) but they are also the darkest red-purple. As an added bonus, Ann boasts the ability to produce sporadic flowers all summer long! This results in Ann having an average of 13 weeks of flowers, as compared to Jane’s 10 weeks and Betty’s 8 weeks.
These five cultivars are generally available at garden centers during spring. Ann and Jane can be found at many “Big Box” stores. All five can be purchased at “good” independent garden centers and, as a last resort, from mail-order/Internet nurseries.
For more information about these and other magnolias, see Florida Extension publication, ‘Jon Jon’ Magnolia: A Late-Flowering Deciduous Magnolia for Northern Florida, and other magnolia publications here. Also, Magnolia Society International is a great resource with a very informative website. (Note the slide show below of Jon Jon, Ann, Betty, Daybreak and Jane.)
[portfolio_slideshow id=4059]
by Carrie Stevenson | Feb 10, 2015
After storms and when homeowners are doing “spring cleaning” around their yards, Extension agents are routinely asked about whose responsibility it is to maintain a tree along a property line. This becomes particularly important in a situation where a property owner’s tree or branch falls and causes damage to their neighbor’s home or possessions.
To clarify this often contentious issue, reference to legal experts is necessary. In a series of publications called “The Handbook of Florida Fence and Property Law,” two attorneys and a University of Florida law student explain several statutes that give us direction. The section on “Trees and Landowner Responsibility” goes into further detail and cites case-law, but for ease of reading it is summarized below.
Situation 1: Removing a healthy tree on a shared property line.
If two neighbors share a tree on their property line and one of them wants to remove it, the adjoining landowner must give their permission. Removing trees can impact property value, heating/cooling bills, or aesthetic value. Without a neighbor’s consent, the landowner cutting down a tree can be legally liable for damages.
Hurricanes can have serious impacts on trees in their path. Photo credit: Pensacola News Journal
Situation 2: Responsibility for overhanging branches and roots.
Let’s imagine a big spring storm hits your neighborhood, with tons of rain, wind, and lightning. You wake up in the morning and see that a large branch fell from your neighbor’s tree and crushed your kids’ basketball goal. If branches from the neighbor’s tree were otherwise healthy, they are not responsible for any damages resulting from the tree. If it was dead, however, and their negligence contributed to the branch falling, they will be responsible for damages.
Keep in mind that if the neighbor’s tree/branches/roots are in good health but interfering with something in your yard, you may trim them at your own expense. The same goes for your tree hanging in their yard, so while it’s not required, it’s always good to have a conversation first to let them know your plans.
After Hurricane Ivan, this tree’s root system completed uprooted and destroyed and adjacent fence. Photo credit: Beth Bolles
Situation 3: Hurricane Ana, the first big storm of 2015, blows your neighbor’s tree over, into your yard.
Just like the situation with branches and roots, the same principle goes for an entire tree falling on adjoining property—if the tree was alive, it’s the responsibility of the person whose yard it fell in. If it was dead when it fell, it’s the responsibility of the tree’s owner to pay for damages.
In a complicated situation involving property damage, the saying, “good fences make good neighbors” only goes so far. Be sure to note the health of your trees throughout the year and trim back dead or dying branches. If you see serious decay or have concerns about a tree’s health, contact your county Extension office or a certified arborist. Finally, if the circumstances aren’t easily determined, be sure to contact a licensed attorney and/or your insurance company for direction.
by Gary Knox | Feb 3, 2015
Figure 1. Topping is the drastic removal of large-diameter wood (typically several years old) with the end result of shortening all stems and branches. Topping is not recommended for crapemyrtle.
As the holidays fade and the New Year begins, we often see crapemyrtles being “mutilated” from improper pruning: main stems that are several years old are cut back, often leaving branch stubs 2 – 5 inches or more in diameter. This form of crapemyrtle mistreatment goes by various names, including topping, heading, stubbing, rounding, dehorning and (my favorite) “crape murder”.
Whatever you call it, topping a crapemyrtle is almost always unnecessary. Over the years, many people viewed this type of improper pruning and unthinkingly perpetuated the practice in their own yards, not realizing the unfortunate consequences.
Research at the University of Florida found that topping crapemyrtle delays flowering up to one month. For example, unpruned trees may begin flowering in June whereas topped trees begin flowering in July. This research also found topping reduced the number of flowers and shortened the flowering season. Finally, topping stimulated more summer sprouting from roots and stems. Sprouting results in greater maintenance since sprouts are usually removed to maintain an attractive plant appearance.
Figure 2. With proper cultivar selection and placement in the landscape, crapemyrtle develops into a beautifully shaped tree that rarely needs pruning. This crapemyrtle is Red Rocket®.
If a crapemyrtle is located where it requires routine pruning to fit into its surroundings (for example, under the eave of a roof), it should be replaced with a smaller growing crapemyrtle. A dwarf crapemyrtle (maturing at a height of 5 feet) would fit this location well. Medium crapemyrtle cultivars (growing up to about 15 feet in height) and tall or tree-size crapemyrtle cultivars (often growing 20 – 30 feet tall in 10 years) are best reserved for open areas.
Crapemyrtle thrives under full sun conditions in areas with ample room for the cultivar size and away from walkways and roads. Proper selection of crapemyrtle cultivar and proper placement in the landscape can result in a low maintenance crapemyrtle without the need for significant pruning.
For more information, please see Crapemyrtle Pruning.
