by Sheila Dunning | Jun 22, 2016
The showy chaste tree makes an attractive specimen as the centerpiece of your landscape bed or in a large container on the deck. Easy-to-grow, drought resistant, and attractive to butterflies and bees, Vitex agnus-castus is a multi-stemmed small tree with fragrant, upwardly-pointing lavender blooms and gray-green foliage. The chaste tree’s palmately divided leaves resemble those of the marijuana (Cannabis sativa) plant; its flowers can be mistaken for butterfly bush (Buddleia sp.); and the dry, darkened drupes can be used for seasoning, similar to black pepper, making it a conversation piece for those unfamiliar with the tree.
Vitex, with its sage-scented leaves that were once believed to have a sedative effect, has the common name “Chastetree” since Athenian women used the leaves in their beds to keep themselves chaste during the feasts of Ceres, a Roman festival held on April 12. In modern times, the tree is more often planted where beekeepers visit in order to promote excellent honey production or simply included in the landscape for the enjoyment of its showy, summer display of violet panicles.
Chaste tree is native to woodlands and dry areas of southern Europe and western Asia. It will thrive in almost any soil that has good drainage, prefers full sun or light shade, and can even tolerate moderate salt air. Vitex is a sprawling plant that grows 10-20 feet high and wide, that looks best unpruned. If pruning is desired to control the size, it should be done in the winter, since it is a deciduous tree and the blooms form on new wood. The chaste tree can take care of itself, but can be pushed to faster growth with light applications of fertilizer in spring and early summer and by mulching around the plant. There are no pests of major concern associated with this species, but, root rot can cause decline in soils that are kept too moist.
by Matthew Orwat | Jun 1, 2016
Young nymphs of the eastern lubber grasshopper, Romalea microptera (Beauvois), clustered on a citrus reset (young citrus tree). Photograph by John Capinera, University of Florida.
The Eastern Lubber Grasshopper, also known colloquially as the “Georgia Thumper,” can be highly destructive to a variety of vegetable crops. This May many growers and vegetable gardeners have reported unusually high numbers of nymphs, the juvenile form of the grasshopper.
This observation is consistent with the usual increase of nymphs in vegetable gardens during the spring months. The old adage of “an ounce of prevention is worth a pound or cure” applies here. Now is the time to exert control over the nymphs before they mature. Adults do the greatest crop damage in July and August.
Additionally, adult females lay their eggs in the summer, with hatching the following April. Reducing the numbers this year will reduce the numbers in the following years.
The first step to control of the Eastern Lubber Grasshopper is prevention. They like to feed on weedy vegetation, so reducing weed cover in and around crops will reduce the incidence of Eastern Lubber damage. Short vegetation does not usually provide enough forage for grasshoppers, so mowing vegetation around fields is an excellent preventative strategy.
Although most home gardeners can control Eastern Lubber Grasshoppers by mechanical means (hand picking) this is usually not a feasible option for large gardens or small farm plantings. Fortunately, there are several products on the market for commercial producers to use.
Keep in mind, grasshoppers are much easier to control while they are in the young nymph stage, so early action is paramount when nymphs are observed. Several effective insecticides include carbaryl, bifenthrin, cyhalothrin, permethrin, and esfenvalerate. Look at the label to find these active ingredients, since they are sold under various brand names.
For more information about the Eastern Lubber Grasshopper or for specific crop recommendations, please visit this UF/IFAS publication on Grasshoppers and the UF/IFAS Featured Creatures Entomology Page.
by Matt Lollar | May 24, 2016
From time to time I am reminded of how little I know. Honestly, I am reminded on a daily basis. A few weeks ago someone asked me about the purple things hanging from the trees. Luckily, the person gave me some good southern directions on where I could find one of these things hanging around in Marianna. So I drove out to the site to get a better look. What I saw hanging in the tree was a three-sided, purple triangle about two feet tall and a foot wide. It looked to me like someone got a box kite stuck in a tree. Upon further research, it was determined this box kite like thing was a monitoring trap for the emerald ash borer (EAB).
A woman hanging an emerald ash borer trap in a tree. Photo Credit: Texas A&M University
The emerald ash borer (EAB) is a destructive, exotic wood-boring beetle native to Asia. It was first discovered in North America in July 2002 and has made a home in Michigan, Ohio and Ontario, Canada. Millions of ash trees have been killed by the EAB in Michigan and invested ash tree nursery stock in other states indicates the potential for increased spread of the pest. EAB has made its way to the south and has been found in Louisiana and Arkansas.
Monitoring traps are not the only means of EAB detection. A proactive approach utilizing observant citizens can help keep an eye out for potential populations. You can use these tips to monitor your community for emerald ash borers:
Ash Tree Identification – Ash trees are identified by their (1) opposite branching pattern, (2) compound leaves with 5-9 leaflets, and (3) diamond shaped bark ridges on mature trees.
A compound leaf of an ash tree. Photo Credit: FDACS
Woodpecker Damage – Of course, not all woodpecker damage on ash trees is associated with EAB infestation, but woodpecker damage in the upper part of the tree can indicate their presence. The woodpecker damage is usually accompanied by vertical cracks in the bark.
Canopy Thinning – As the attack progresses, bark cracking continues and the canopy in the upper half of the tree begins to thin.
Michigan ash tree showing decline due to Emerald ash borer. Photo Credit: USDA
Tunnels and Holes – The emerald ash borer makes distinctive S-shaped tunnels that differ from damage from other borers.
EAB Damage (left) VS Other Borer Damage (right). Photo Credit: Texas A&M University
This beetle hitchhikes on firewood and infests new areas at an alarming rate. Although the EAB has not yet been detected in Florida, transporting firewood from other states puts Florida ash trees at risk. Your help is needed to detect possible infestations so they can be quickly eradicated. The information available at the following links will help you identify the EAB, EAB host trees, and infestation symptoms.
by Les Harrison | May 17, 2016
The hectic pace to contemporary life can justifiably be compared to the seemingly erratic behavior of insect pollinators. Darting from flower to flower with no apparently logical progression for choice of blooms, all the while emitting a mind numbing buzz.
Adult large carpenter bee, Xylocopa sp. Photograph by Paul M. Choate, University of Florida.
This incessant and unending grind of bouncing from task to task has created an atmosphere of tedium and monotony which has become the anthem of many adults. As quick as one chore is complete, another replaces it. Russian composer Nokoli Rimsky-Korsakov wrote what might be considered today’s theme song at the dawn of the 20th century. “Flight of the Bumblebee” catches the frantic haste at which this insect functions, as well as its commonly encountered cousin the carpenter bee.
Bumblebees and carpenter bees are very similar in behavior, coloration and size. The easiest way to differentiate these insects is by their abdomen, the body segment furthest from the head. Bumblebees have an abdomen thickly covered in fine hairs. Carpenter bees lack the fine hairs and have a shiny abdomen.
Xyloxop micans Lepeletier, as the large carpenter bee is known scientifically, is one of more than 500 species worldwide. Almost all members of this genus build their nest by burrowing into dead wood. In the wilds of the panhandle this usually means deadfall timber of almost any sort. Unfortunately, in the areas which include human structures, the nesting sites include wooden timbers and siding.
Unlike European honeybees, the carpenter bees are labeled as solitary bees. There may, however, be several nests in close proximity to these active insects.
Nests are composed of a single parent that lays eggs in a segmented tubular nest. The nest openings are a nearly perfect 5/8 inch (16 mm) hole. Each nest has only a single opening, but multiple tunnels will branch off the main passage. These bees do not eat the wood removed to create the nest channels. Sometimes the holes are not visible to the observer, but the wood emits a buzzing or humming sound when these bees are nesting in hidden locations. In many cases small quantities of saw dust can be found on the ground under the hidden nest.
Heavy or repeated infestations can weaken structural timbers and severely damage siding. Decay and breakage will ultimately follow an untreated incursion.
While the damage caused by carpenter bees can be quite expensive, they may attract an even more destructive predator. Woodpeckers, especially the native pileated woodpecker, dine on carpenter bee larvae at every opportunity. These feathery insect assassins are attracted to the vibrations and hums of the bees hidden in wood. In some cases, the wood acts as a resonator and amplified the insect noise which assures an aerial assault. When discovery of the larvae is confirmed, the woodpeckers attack with a ferocity seldom seen in nature. The rapid-fire staccato of their hammering is loud and devastating.
Structural supports are compromised far beyond the damage done by the carpenter bees, and at a quicker rate. Siding is often shredded and left completely useless.
Commonly available insecticides can help control the carpenter bee population and reduce the prospects of woodpecker damage. Unfortunately, this only adds one more item to the long list of chores and task of contemporary adults.
For more information:
Featured Creatures: Large Carpenter Bees
by Blake Thaxton | May 17, 2016
In the last few weeks, more garden pests have arrived! It is a fact of life in northwest Florida that we will have a few things in our garden including heat, moisture (humidity and rainfall), and BUGS! With a cooler spring the arrival of some of the troublesome pests in the garden seemed to be delayed a few weeks. It was nice while it lasted but the insect pests are here to stay until frost in the fall or winter (at least we hope for a frost this year).
There are thousands of insects that you can see in your garden. It’s wise to identify them before making a decision to spray an insecticide or remove them by another method. Insect samples can be taken to your local county extension office for identification.
In this article we will just discuss one of the top insect pests in the vegetable garden, caterpillars, and what you can do about them.
Mature larva of the cabbage looper. Photograph by John L. Capinera, University of Florida.
Beet armyworms, fall armyworms, hornworms, cabbage loopers, southern armyworms, tomato fruitworms, and other caterpillars love to feed on tomato foliage and fruit. They will show up eventually on tomato plants in the garden, if not this year then in the future. These larvae are immature moths and cause a lot of damage if left unchecked. The homeowner can control them effectively with Organic Materials Review Institute (OMRI) approved pesticides. A bacterial biological insecticide called Bacillus thuringiensis, also referred to as B.t., can be very effective in controlling these caterpillar pests. B.t. is a stomach toxin to these pests and will cause them to quit eating and starve to death. The key to using B.t. effectively is to routinely apply it before the caterpillars hatch from their eggs as the smaller caterpillars are easiest to control. Larger caterpillars are more difficult to control.
For more information related to using OMRI pesticides:
Organic Vegetable Gardening in Florida
Insecticides for Organic Commercial & Backyard Vegetable Production
by Julie McConnell | May 5, 2016
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. 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.
The showy chaste tree makes an attractive specimen as the centerpiece of your landscape bed or in a large container on the deck. Easy-to-grow, drought resistant, and attractive to butterflies and bees, Vitex agnus-castus is a multi-stemmed small tree with fragrant, upwardly-pointing lavender blooms and gray-green foliage. The chaste tree’s palmately divided leaves resemble those of the marijuana (Cannabis sativa) plant; its flowers can be mistaken for butterfly bush (Buddleia sp.); and the dry, darkened drupes can be used for seasoning, similar to black pepper, making it a conversation piece for those unfamiliar with the tree.
