Video: Evergreen Shrubs in the Fall

Video: Evergreen Shrubs in the Fall

Fall is the season for leaf color changes on many plants, but we are often concerned when we see evergreen plants with brown leaves. Learn what is normal browning for evergreens and when to seek more help from UF IFAS Extension Escambia County.

What Can Be Done To Prevent Tree Dieback?

What Can Be Done To Prevent Tree Dieback?

Tree dieback is a complex syndrome and slow developing. Dieback is essentially a process in which trees lose leaves and limbs. This usually occurs as a result of severe stress to the tree’s bark or root system, but could be a result of a declining life cycle.

It’s important to note that there is a significant balance between a tree’s root system and the number of leaves and limbs it can support.  For example, if a tree loses part of its root system, possibly due to disease or lawn equipment damage, the tree will forfeit a portion of its leaves. Dieback doesn’t happen overnight, though. It’s a slow process, with larger trees taking much longer time for signs of stress to emerge.  However, a large tree root system is very sensitive to damage, whereas a small tree will adapt quickly and is much more resilient to damage.  So, what can be done to prevent dieback in trees?

First and foremost, trees, like all living things, have a natural life cycle.  Regardless of how you care for your trees, dieback will occur. The most important management measure in extending the life of a tree is to protect the root system and bark.

With each passing year, a tree grows new bark in the rejuvenation process.  The bark replacement process inevitably becomes more difficult as the tree gets older and in turn the tree is more and more susceptible to dieback. If the bark becomes damaged, especially later in the tree’s life cycle, then fungi and insects have a much greater chance to cause serious harm. Treating bark damage with a wound dressing to prevent decay is the recommended procedure.

Lichens come in many forms and are commonly blamed for the decline and death of trees and shrubs, however they do not cause harm. Credit. Sydney Park Brown and Joseph Sewards, UF/IFAS.

A common misconception is that epiphytes, such as lichens and Spanish moss, are tree diseases. Epiphytes are known as “air plants” and thrive in the Panhandle. They survive on moisture and nutrients in the atmosphere and are harmless to trees. However, a tree that becomes inundated with epiphytes may be an indicator of excessive soil moisture, which may lead to root rot.

Lawn weed killers can have detrimental effects to trees, even if the application seems to be from a safe distance.  When using a weed killer near a tree’s root system, confirm on the label that the product is designed to kill green growth only. It can’t be overstated that excessively fertilizing an old tree will greatly accelerate the decline of the tree. Some may think this will stimulate a tree and extend its life, but instead it will do the opposite. Young trees can tolerate fertilizer applications, as they need crown growth. Older trees will simply become top heavy, and structural damage will likely occur.

Don’t forget, trees need space too.  A mature tree forced to occupy a small space will simply not adapt. Be sure to have adequate spacing when planting younger trees and shrubs in the vicinity of older trees. Also, keep your trees pruned away from touching structures and utilities.

Tree dieback is a complex issue to manage. By following these measures, you can help extend the life of your trees and continue to have a picturesque landscape.

For more information on tree dieback, contact your local county extension office.

Please visit Florida Friendly Landscaping, http://fyn.ifas.ufl.edu/, for more information on maintaining your landscape.

For more general  information on lichens, please see UF/IFAS EDIS document “Spanish Moss, Ball Moss and Lichens-Harmless Epiphytes” by Joe Sewards and Dr. Sydney Park Brown: https://edis.ifas.ufl.edu/pdffiles/EP/EP48500.pdf

UF/IFAS Extension is an Equal Opportunity Institution.

Creating Space for Wildlife

Creating Space for Wildlife

Bald eagles and other large birds of prey have made a comeback in Florida.

Florida has all the elements of a wild animal’s paradise. The state has abundant rain and water sources, lush vegetation, plenty of food, and tons of nesting and hiding places. In our state and national parks, conservation easements, open waters, and acres of ranch land, large populations of animals can thrive. Particularly in areas with fewer people, healthy populations of even large animals like black bears, alligators, and panthers can maintain substantial territories. However, human migration into and throughout Florida is increasing at as steady a rate as ever. Retirees have long fled their cold northern winters to move part or full time to Florida. Now, the ability for many working people to telecommute from anywhere has made it attractive for younger families from all over the country to join us.

A black bear helps himself to a drink from the swimming pool of a Florida home. Photo provided by Patty Underwood/FWC

With more people comes the need for more housing. Some are content with high rise condos that leave a smaller footprint, but these are often located right on the water and can displace coastal wildlife and vegetation. For the thousands of families moving in weekly, more subdivisions, roads, stores, and schools are necessary. Inevitably, these lead to human-wildlife interactions that may or may not be positive experiences. In fast-growing south Santa Rosa County, I see almost daily reports of large black bears in backyards and trash cans. For smaller mammals, the threat of being hit by a car is unfortunately very common. For nearly every call we get about an exciting manatee sighting, we get word of a nerve-wracking interaction with a snake.  As civilization moves closer to forested, once-wild areas, wildlife can be squeezed out, left without the protection of natural cover and drawn to human food and habitat.

A lush backyard landscape surrounds a recognition sign from the National Wildlife Federation. Photo credit: Carrie Stevenson, UF IFAS Extension

There are plenty of ways we can co-exist, though. A Florida-friendly yard is a wildlife-friendly yard, and those who go the extra mile can even be recognized by the National Wildlife Federation for their efforts. There are several steps one needs to take to become wildlife-friendly. The most important include providing food, water, and cover, so the animals’ basic needs are met. Actions like removing invasive species, keeping pets supervised when outdoors, and adding layers of vegetation are also excellent ways to attract and protect native creatures.

While small and medium sized animals can find shelter in a single yard, it takes neighborhood cooperation to be a haven for something larger, like deer, bears, birds of prey, or large tortoises. Some neighborhoods are designated from the beginning to include conservation easements that serve as amenities to the neighborhood. They include trails, shady waterfront areas, and plenty of space for wildlife. It is important when moving into one of these neighborhoods that each homebuyer understands and respects the purpose behind conservation areas. Residents of older, existing neighborhoods can also work together to designate common areas and stretches of adjoining yards as wildlife-friendly corridors, allowing more animals to use the space safely.

A gopher tortoise burrow is noted by a sign in a local city park. The tortoise is co-existing peacefully with its neighbors! Photo credit: Carrie Stevenson, UF IFAS Extension

In my own neighborhood in the city limits, a gopher tortoise has moved in and become a neighborhood mascot of sorts! When alerted to the presence of its burrow, the city brought in a sign explaining the animal’s protected status and crucial role in the environment. Floridians share their citizenship with thousands of other species. These breathtaking birds, fish, mammals, reptiles, and insects are integral to the health of our land and water. By taking steps to look out for their well-being, we are also providing for our own.

Hickory Gall and Anthracnose, a Deadly Combination?

Hickory Gall and Anthracnose, a Deadly Combination?

As homeowners, we do value our trees and no one wants to lose a shade tree especially on the house’s south side in Florida.  On a recent site visit, a hickory tree had multiple concerns.  Upon closer inspection, the tree had a bacterial infection about 30” off the ground with a smelly, black-brown ooze seeping forth.  The leaf canopy was riddled with beetle holes and leaf margins were chewed by caterpillars.  When leaves were viewed under the microscope, thrips (insects) and spider mites were found running around.   The biggest homeowner cosmetic concern arose from hickory anthracnose (fungus) and upon closer inspection found the leaves to have hickory midge fly galls.  The obvious question is should the tree come down?  I’ll have you read the whole article before giving you the answer.

Whole Hickory Gall

Each hickory gall is approximately 3/16″ wide.

Hickory anthracnose or leaf spot as seen in the banner photo is caused by a fungal infection during the wet summer months in Florida.  The homeowner can usually recognize the disease by the large reddish brown spots on the upper leaf surface (sending a sample to the NFREC Plant Pathology Lab will confirm the diagnosis) and brownish spots with no formal shape on the bottom.  Be sure to rake and remove all leaves to prevent your disease from overwintering close to the tree thus reducing infection next year.

Gall Half

A hickory gall has been cut in half to show the leaf tissue.

The fungus can be lessened by good cultural practices and appropriate fungicidal applications.  Please remember it is best left to professionals when spraying a large tree.  This alone is not cause to remove your tree.

Hickory gall is caused by the hickory midge fly, an insect that lays eggs in the leaf tissue.  The plant responds by building up tissue around each egg almost like the oyster when forming a pearl.

As the gall tissue grows, eggs hatch and larva start to feed on this tissue.  The larva will continue to

Gall Larva

The larva has eaten all soft material inside the gall and is ready to pupate.

feed until it is ready to pupate within the gall.  After forming a pupa, the midge fly will eventually emerge as an adult and females will continue to lay eggs on other leaves.  The galls are more of a cosmetic damage and because your hickory leaves will fall from the tree as winter comes, the galls will normally not cause enough damage to worry about each year.  Once again good cultural practices and disposal of each year’s leaves will reduce the gall numbers next year.

In a large tree with many leaves, foliar feeding by beetles and caterpillars do cause damage though the leaves will still produce enough food (photosynthesis) to keep the tree alive.  Most of us never climb our trees to look at leaves to see the small insects/mites and there are more than enough leaves to maintain tree health.

The biggest concern during my site visit was their tree’s bacterial infection.  A knife blade was pushed into the wound area and went in less than 1/4″.  The homeowner was instructed to look at bactericide applications.  In the end, this hickory tree with so many problems is still shading the home and helping cool the house.  It is still giving refuge to wildlife and beneficial insects.  When in doubt give our trees the benefit and keep them in place.  Remember your local Extension agent is set up to make site visits and saving a tree is time well spent.

 

Rainlily: A Rewarding Bulb for Panhandle Gardeners

Rainlily: A Rewarding Bulb for Panhandle Gardeners

Bulbs are my favorite class of ornamental plants.  They generally are low maintenance, come back reliably year after year, and sport the showiest flowers around.  While many bulbs like Daylily, Crinum and Amaryllis are very common in Panhandle landscapes, there is a lesser-known genus of bulbs that is well worth your time and garden space, the Rainlily (Zephyranthes spp.).

Rainlily, aptly named for its habit of blooming shortly after summer rainfall events and a member of the Amaryllis family of bulbs, is a perfect little plant for Panhandle yards for several reasons.  The plant’s genus name, Zephyranthes – which translates to English as “flowers of the western winds”, hints at the beauty awaiting those who plant this lovely little bulb.  From late spring until the frosts of fall, Rainlily rewards gardeners with flushes of trumpet-shaped flowers in shades of white, pink, and yellow, with some hybrids offering even more exotic colors.  While these individual flowers typically only persist for a day or two, they are produced in “flushes” that last several days, extending the show.  Though Rainlily flowers are the main event for the genus, beneath the blooms, plants also offer attractive, grass-like, evergreen foliage.  These aesthetic attributes lend themselves to Rainlily being used in a variety of ways in landscapes, from massing for summer color ala Daylilies, to use around the edges of beds as a showy border like Liriope or other “border” type grassy plants.

Unknown Rainlily species blooming in a raised bed. Photo courtesy of Daniel Leonard.

Continuing along the list of Rainlily attributes, the genus doesn’t require much in the way of care from gardeners either.  Most species of Rainlily, including the Florida native Z. atamasca, have no serious pests and are right at home in full sun to part shade.  Once established, plants are exceedingly low-maintenance and won’t require any supplemental irrigation or fertilizer!  Some Rainlily species like Z. candida even make excellent water or ditch garden plants, preferring to have their feet wet most of the year – putting them right at home in the Panhandle this year.  And finally, all Zephyranthes spp. do very well in containers and raised beds also, adding versatility to their use in your landscape!

The one drawback of Rainlily is that they can be somewhat difficult to find for sale.  As these bulbs are an uncommon sight in most garden centers, to source a specific Zephyranthes species or cultivar, one is probably going to need to purchase from a specialty internet or mail-order nursery.  As with other passalong-type bulbs though, the absolute best and most rewarding way to obtain Rainlily is to get a dormant season bulb division from a friend or fellow gardener who grows them.  There are many excellent unnamed or forgotten Zephyranthes cultivars and seedlings flourishing in gardens across the South, waiting to be passed around to the next generation of folks who will appreciate them!

Even if you must go to some lengths to get a Rainlily in your garden, I highly recommend doing so!  You’ll be rewarded with years of low-maintenance summer color after the dreariest of rainy days and will be able to pass these “flowers of the western wind” on to the next gardening generation.  For more information on growing, sourcing, or propagating Rainlilies, check out this EDIS publication by Dr. Gary Knox of the UF/IFAS North Florida Research and Education Center (NFREC) or contact your local UF/IFAS Extension office!  Happy Gardening!