Fence Row Weed Control…Optional?

Fence Row Weed Control…Optional?

Nothing looks better than a fence clean from weeds right?  It all depends on the goal you have in mind.  If you want to one day receive the infamous honor of “yard of the month”, than you might want the cleanest and straightest fence around.  If you have goals of providing a habitat for wildlife and beneficial insects, some selective strategies need to be implemented.  Providing a habitat for beneficials can easily be achieved through minimal maintenance and selective plant removal.

Clean Fence Row

A typical clean fence row. Photo Credit: Iowa State University Extension

If you are starting with a clean fence free of herbaceous plants, shrubs, vines, and trees then you have two options: Replant vegetation for the ideal habitat(1) or allow for natural plant succession to take its course(2).  If you chose option 2, that’s it, you’re done. However, if you chose option 1 then you begin the search of garden centers for desirable plants.

In order to pick the best plants, you will need to think about what you want to attract.  Do you want to attract vertebrates, invertebrates, or a little of both?  Vertebrates are attracted to plants that provide shelter and food.  A good start for selecting plants would be to read the publication “Native Plants That Benefit Native Wildlife in the Florida Panhandle”.

As you already know, pollinator insects are attracted to nectar and pollen.  However, beneficial insects cannot survive on just eating bad bugs and they need supplemental nutrition.  They receive this supplemental nutrition by way of extrafloral nectaries.  Extrafloral nectaries are nectar-producing glands located on plant parts other than the flowers.  They can be located on plant leaves, stems, or fruit.  A list of plants containing extrafloral nectaries can be found in the publication “Many Plants Have Extrafloral Nectaries Helpful to Beneficials”.

A milkweed assassin bug.

A milkweed assassin bug. Photo Credit: Texas A&M University.

Although it’s great idea to attract wildlife to your fencerows, it is important to choose plant material based on your fence’s location in vicinity to your house.  Fire can easily jump from plant material to fences to your house.  The Firewise Communities Guidelines should be followed for landscaping your home.

Common Live Oak Problems and Solutions

Common Live Oak Problems and Solutions

 

The Live Oak (Quercus virginiana) is one of the most iconic figures of the Deep South. Mentioning the words Live Oak invokes all sorts of romantic nostalgia of yesteryear and the reputation is not unearned. In fact, many Live Oaks still stand that were growing on American soil when the first English settlers set foot on Plymouth Rock. They are long-lived, picturesque trees that also happen to be nearly bulletproof in the landscape. Given these factors, it is not surprising that Live Oak is far and away the most common tree included in both residential and commercial landscapes in the Coastal South. However, even the venerable Live Oak is not without its problems; this article will discuss a few of the more common issues seen with this grand species.

The Angel Oak near Charleston, SC

The Angel Oak near Charleston, SC

Few conditions afflict live oak but when they do, improper planting or cultural practices are usually at play. Observing the following best management practices will go a long way toward ensuring the long-term health of a planted Live Oak:

  • Remember to always plant trees a little higher than the surrounding soil to prevent water standing around the trunk or soil piling up around it, both of these issues frequently cause rot to occur at the base of the tree.
  • If planting a containerized tree, remember to score the rootball to prevent circling roots that will eventually girdle the tree. If planting a B&B (Balled and Burlap) specimen, remember to remove the strapping material from the top of the wire basket, failure to do this can also result in the tree being girdled.

Live Oak has few insect pests but there are some that prove bothersome to homeowners. The following are two of the most common pests of Live Oaks and how to manage them:

Typical galling on Live Oak

Typical galling on Live Oak

 

Galls are cancerous looking growths that appear on the leaves and twigs of Live Oak from time to time and are caused by gall wasps that visit the tree and lay their eggs inside the leaf or stem of the plant. The larvae hatch and emerge from the galls the following spring to continue the cycle. These galls are rarely more than aesthetically displeasing, however it is good practice to remove and destroy gall infected stems/leaves from younger trees as gall formation may cause some branch dieback or defoliation. Chemical control is rarely needed or practical (due to the very specific time the wasps are outside the tree and active) in a home landscape situation.

  • Black Twig Borers can also be problematic. These little insects seldom kill a tree but their damage (reduction of growth and aesthetic harm) can be substantial. Infestations begin in the spring in Northwest Florida, with the female twig borer drilling a pen-head sized hole in a large twig or small branch and then laying her eggs in the ensuing cavity. She then transmits an ambrosia fungus that grows in the egg-cavity, providing food for the borer, other borer adults, and her offspring that take up residence and over-winter in the twig. The activity of the insects in the twig has an effect similar to girdling; the infected twig will rapidly brown and die, making removal and destruction of the infected branches a key component

 

In conclusion, though there are a few problems that can potentially arise with Live Oak, its premier status and continued widespread use in the landscape is warranted and encouraged. It should be remembered that, relative to most other candidates for shade trees in the landscape, Live Oak is extremely durable, long-lived, and one of most pest and disease free trees available. Happy growing!

Does Your Lawn Guy Need a License?

If your lawn and landscape care professional applies fertilizer as a part of his/her services, then the answer is yes. Since January 2014, the Florida Department of Agriculture and Consumer Services (FDACS) has required that all commercial fertilizer applicators have a Limited Fertilizer License.

UF/IFAS File Photo.

UF/IFAS File Photo.

So what does FDACS define as a fertilizer? You may be surprised at what is considered a fertilizer under the statute that governs this license. The following are included:

  • Lawn or landscape fertilizers
  • Organic fertilizers
  • Any product that contains plant nutrients including compost
  • Lime and all other products that influence soil acidity/alkalinity
  • Substances that promote plant growth
  • Any other substance that provides a soil corrective measure

In order to obtain this license, lawn care professionals attend a science-based training session called Green Industries Best Management Practices (GI-BMPs) that teach environmentally friendly landscaping practices in order to protect Florida’s water quality. These practices also save the homeowner money, time, and effort; increase the health and beauty of the home landscape; and protect the health of your family, pets, and the environment. The training is led by UF/IFAS Extension professionals. Attendees must pass a post-training exam and then can receive a license valid for 4 years.

In order to check whether your lawn care professional has a Limited Fertilizer License, check the FDACS site here. Every applicator must have his/her individual license.

 

Biological Control in Action!

Biological Control in Action!

Pink aphid feeding on plant

Aphids (Macrosiphum gaurae) feeding on gaura. Photo: Julie McConnell, UF/IFAS

Every day, if I get home before the sun goes down, I like to walk around my garden and see how things are growing. At this time of year there are always new surprises in the garden – plants leafing out after a winter break, new flower buds and blooms, and of course sometimes garden pests.

My daughter and I collected some flowers last weekend and after they sat on the table for a few minutes I noticed pink bugs crawling around on the gaura stems. On further inspection I realized the stem was covered in aphids which made me go out to look at the entire plant. I found a prolific population

of aphids on the gaura and also lady beetle larvae hunting and eating the aphids! Instead of mixing up a bottle of insecticidal soap I decided to let the lady beetles do their job and just monitor the situation.

Multicolored Asian Lady Beetle Larvae feeding on aphids.

Multicolored Asian Lady Beetle Larvae feeding on aphids. Photo: Julie McConnell, UF/IFAS

Five days later I went to show my example of natural biological control to a visiting friend and we could not find a single aphid on my plant. This may not be the typical response, usually I see some level of both predator and prey but in this instance the lady beetle did a fantastic job of controlling the aphids.

So, did they eat every last one? Probably not, they likely ate many of them and the others left the plant because the predator pressure was too great. However, either scenario saved my plant from severe damage which was the overall goal.

 

What’s Wrong with My Camellia Leaves?

What’s Wrong with My Camellia Leaves?

Recently, a home gardener brought in some strange looking new leaves on his camellia. The youngest leaves were thick and fleshy and looked more characteristic of a succulent type plant than a camellia. What’s wrong with these leaves?

Camellia leaf gall infection resulting in fleshy yellow and pink leaves. Note the contrast with a healthy uninfected leaf. Photo credit: Mary Derrick, UF/IFAS.

Camellia leaf gall infection resulting in fleshy light green and pink leaves. Note the contrast with a healthy uninfected leaf. Photo credit: Mary Derrick, UF/IFAS.

The culprit is a fungus Exobasidium camelliae whose spores are carried by the wind in search of camellias. This fungus infects camellias, especially sasanquas; it will not infect any other plant species. The disease it causes is known as camellia leaf gall and is most commonly seen here in the Florida panhandle in April. The frequent wet weather this winter and spring created favorable conditions for disease development.

The symptoms of the disease are easy to distinguish and really stand out against the typical dark green leaves of the camellia. Leaves become thick and fleshy and the color ranges from light green to cream to pink. As the disease progresses and the galls mature, the lower leaf surfaces of the leaves will peel away to reveal a white underside laden with fungal spores. Wind and rain will take these new spores to other parts of the camellia or other camellias in the vicinity where they will lay dormant and cause infection the following spring. Eventually the galls will turn brown and dry up.

The underside has pealed away revealing white fungal spores. Photo credit: Mary Derrick, UF/IFAS Extension.

The underside has pealed away revealing white fungal spores. Photo credit: Mary Derrick, UF/IFAS Extension.

Camellia leaf gall is not a serious disease that requires chemical intervention for the homeowner. Simply remove the galls and put them in the trash. The earlier you remove the galls the better; the risk of further infection can be reduced if the galls are removed before the undersides peel and expose their spores. Any that have fallen to the ground can spread the disease and need to be removed.

 

 

For more information:

Camellias at a Glance

Camellia Leaf Gall

 

 

Tipping the Scales

Tipping the Scales

Scales on a Chinese Elm.

Scales on a Chinese Elm.

Scales on a Chinese Elm.

Scales on a Chinese Elm.

 

 

 

 

 

 

 

 

 

 

Last week as I was basking in the shade of the Chinese Elms (Ulmus parvifolia) in my yard, I noticed some strange lumps on the twigs.  Upon further investigation, I realized the “lumps” were scales.  Scale insects are serious pests of a number of ornamental plants.  Here in Florida there are 13 different families of scales with the most common being armored scales, soft scales, and mealybugs.  Scales have piercing-sucking mouthparts which they use to siphon fluids from the leaves, stems, and sometimes roots of many ornamental plants.  Heavy infestations cause extensive leaf yellowing, premature leaf drop, branch dieback, and eventually plant death.

Scale Biology

The life cycle of a scale begins with eggs being laid beneath wax coverings or beneath the adult female.  Eggs typically hatch in 1 to 3 weeks.  The newly hatched nymphs, called crawlers, move around a plant until they find a spot to feed.  Once a feeding site is located, their piercing sucking mouthparts are inserted into the plant and the crawlers begin to feed and grow.  The males of many scale species develop wings as adults and fly to other plants to reproduce.

The magnolia white scale, Phenacaspis cockerelli, is also called false oleander scale. Image credit http://entomology.ifas.ufl.edu/creatures/orn/scales/false_oleander_scale.htm

The magnolia white scale. Credits: University of Florida

Armored Scales

Armored scales get their armor by secreting a waxy covering over their bodies that is not attached.  The scale lives under this covering and uses it as a protection to feed under.  Armored scales can be almost any color or shape and range anywhere from 1/16 to 1/8 inch in diameter.  For females, these shapes range from circular to oval to long and slender.  The males typically have coverings that are more elongate and smaller than the females.  As adults, the males are tiny, winged, gnat-like insects and are rarely seen.

Hemispherical scale on coontie. Credits: Lyle Buss, University of Florida

Hemispherical scale on coontie. Credits: Lyle Buss, University of Florida

Soft Scales

Similar to armored scales, soft scales secrete a waxy covering, but it is attached to their bodies.  Soft scales can be a number of colors, shapes, and sizes and range anywhere from 1/8 to 1/2 inch in diameter.  Their shapes vary from spherical to nearly flat.

Mealybugs. Credits: James Castner, University of Florida

Mealybugs. Credits: James Castner, University of Florida

Mealybugs

Mealybugs are soft-bodied insects that possess a covering of flocculent, white, waxy filaments.  They are about 1/8 inch in length and usually pinkish or yellowish in color.  Mealybugs have piercing-sucking mouthparts which they use to siphon fluids from the leaves, stems, and sometimes roots of many ornamental plants.  Mealybug damage produces discolored, wilted, and deformed leaves.

Scale and Mealybug Management

  • Cultural Control – Plant inspection prior to purchase or installation is the first line of defense against a scale or mealybug population.  Make sure to inspect the undersides of leaves and plant stems.  Infested sections of plants can be pruned and plant material should be cleaned from the planting area and discarded.  Also, you can increase air flow and decrease humidity by proper installation and pruning.  Over-fertilizing can also increase pest populations.
Larva of a brown lacewing (Neuroptera: Hemerobiidae) preparing to attack and feed on an aphid. The black-colored aphid to the right was probably parasitized by a wasp. Photograph by Lyle J. Buss, University of Florida.

Larva of a brown lacewing. Credits: Lyle Buss, University of Florida.

  • Biological Control – Predators, such as ladybugs and green lacewings, are usually present in large enough numbers to suppress scales and mealybugs to a desirable threshold.  However, broad-spectrum insecticides and bad weather can reduce predator numbers.  Look for signs of predation by inspecting dead scales for jagged holes in their waxy coatings.  If predation signs are present, use more selective chemical controls and oils as opposed to broad-spectrum products.
  • Chemical Control – Timing is everything when it comes to managing scale and mealybug insects.  Crawler activity is more pronounced with the flush of new plant growth in the spring.  Before application, prune infested plant parts off first to promote greater penetration of insecticides into the foliage.  Contact products (acephate, bifenthrin, carbaryl, etc.) must be applied to inhibit the crawler stages of these insects and systemic products (acetamiprid, imidacloprid, thiamethoxam, etc.) can be used on the sessile growth stage.  Plants should be sprayed thoroughly to the point of drip or “run off” from leaves, twigs, and stems.  Repeated applications may still be necessary even if the timing is right, as crawler populations are often large and crawlers like to hide under old waxy scales.  Systemic drenches are also a viable option.  With good spray coverage, horticultural oils can kill scales at all stages of growth.  Refer to the product label for phytotoxicity and temperature guidelines.  Even after successful treatment, the outer coatings of the scales may remain on the plant material for weeks, which can be unsightly.  The best way to determine if scales are dead is to squeeze them.  They will be dry when squeezed if they are dead and they will ooze liquids if they are living (they were at least alive to the point of being squashed).

For insect identification and additional information on scale control, please see:

A Guide to Scale Insect Identification

UF/IFAS Featured Creatures

Your County Extension Office