Monday, November 30, 2009

Plaster Bagworm

This is a microscopic view of a plaster bagworm. The bag in which it lives is made from silken fiber, sand, lint, paint fragments and other debris.
They mainly feed on spider webs, but can also eat fabrics made from natural fibers.
Bagworms outdoors are harmless and can be left alone. For indoor control of bagworms it is important to remove spider webs and vacuum up any of the bagworms you find.
For more information see this UF/IFAS publication:

Mango with Anthracnose

Anthracnose is a fungus that is promoted and spread by heavy rainfall (or irrigation) and dew.

Control is achieved by regular spraying of fungicides at the spray intervals recommended on the label. Spraying starts during flower panicle development and continues until the preharvest waiting period is reached.

To cut down on spraying consider planting Indo-Chinese/Philippine-type mangoes. Many of the mangoes in this group are relatively resistant to anthracnose and will significantly reduce dependence on regular spraying for disease control. The fruit have good flavor and low-fiber flesh (which is a good thing).

For more information about this disease see this UF/IFAS publication: To learn more about growing mango see this publication:

Thursday, November 19, 2009

Do you see these symptoms on your citrus tree?

Water is the single most important factor affecting the severity of this disease.

This disease should be controlled mainly on fruit intended for the fresh market. It is only a serious disease on certain varities of citrus. It mainly affects lemon, Murcotts, Minneola and Temple varities and is often a problem on grapefruit.

For more information about this disease, its causes and control see this link:

Wednesday, November 18, 2009

Can you tell the difference?

Which one of these is the invasive Brazilian pepper tree and which one is the native holly tree? Can you tell the difference?

Brazilian pepper (Schinus terebinthifolius) is a very invasive, non-native tree. Unfortunately, with its bright red berries that become quite obvious this time of year, it sometimes gets used as a holiday decoration. Worse yet, it has been misnamed Florida holly. Make no mistake - this is NOT Florida holly!

Brazilian pepper is one of the most aggressive, non-native invasive species. Once ecologically productive mangrove communities are now pure stands of Brazilian pepper trees. Scrub and pine flatwood communities have also been destroyed by this invasive tree. It can be easily identified by its compound leaf (odd-pinnately compound) with 3 to 13 oblong or elliptic, finely toothed leaflets. The leaves smell like turpentine when crushed. Berries are in clusters. They start off green and turn a bright red when ripe.

For more information about Brazilian pepper and how to control it see this link:

A very nice native holly, dahoon holly, can be mistaken for Brazilian pepper and vice versa. The native holly tree has a simple leaf which is the most easily identifiable difference.
For more information about hollies, see this link:

Monday, November 16, 2009

Fun Festivities at First Annual Farm-City Week

Come enjoy the festivities and see the past, present and future of Pinellas County Agriculture at the Farm-City Week celebration. It will be held at Heritage Village, Saturday, November 21. It starts at 9 AM and goes until 4 PM.

Pick up your fresh veggies and more for Thanksgiving dinner at the Market in the Park. Sample grove and dairy treats, play old time games, learn about Ag-oil and more. There is fun for the whole family.

Friday, November 6, 2009

Citrus Leafminer - A Curiosity

We have had several samples of contorted leaves with serpentine squiggly lines brought to our help desk by concerned citrus owners.

Folks want to know what is happening with their citrus leaves and if it will kill their tree.

This damage is caused by the citrus leafminer (the larval stage of a small moth) and it is mostly cosmetic damage. Mature trees can easily tolerate this damage. Young trees may need to have some horticulture oil sprayed on the new growth to keep this damage to a minimum.

For more information see this publication:

Thursday, November 5, 2009

Cypress Twig Gall Midge

These pretty berry looking appendages on the ends of the twigs are a gall caused by a midge. No cause for alarm -- just think of them as an extra oddity to the plant.

For more information see this publication:

Giant Caterpiller Eats Plumeria

Take a look at your Plumeria to see if this colorful caterpillar is munching away at the leaves. This is the georgeous larva of the plain looking tetrio sphinx moth. One of its favorite host plants is Plumeria. Please consider sparing this caterpillar. Your Plumeria leaves will soon be falling off anyway.

For more information see this publication:

Monday, November 2, 2009

The Case of the Brown-tipped Oak

By Andy Wilson
Extension Specialist

The client was concerned about her oak tree. She had noticed that the last several inches of some of branches were dead, with brown, lifeless leaves. She brought some branch samples to our Lawn and Garden Help Desk, fearing the worst. Was this something that would spread? Would it kill the tree?

Looking at the damage, my first suspicion was twig borers, tiny beetles that bore into branches. These borers introduce a fungus that kills the branch from the point where the beetle has entered the branch to the branch tip. Often this is the last one to 2 feet of the branch. The fungus serves as the food source for the immatures (young). The entrance holes are tiny and my middle-aged eyes, even with the help of reading glasses could not locate a hole. However, a quick look under the microscope revealed the tiny, round hole, almost machine drilled in its appearance.

Twig borers are common on many kinds of trees in our area, including red maple, oaks and some other trees. The damage is usually more cosmetic than threatening to the tree. Eventually the dead branch tips drop to the ground. Insecticidal treatment is usually not necessary.

More information about twig borers can be found here: