Webworms....How to Control Them

Been noticing all the trees with the webs lately? In the Dallas / Worth area, they thrive mostly in the pecan trees. They are called webworms, latin name Hyphantria cunea.

These inch-long green or yellow caterpillars, bristling with silky hairs, are actually moth larvae. In summer and early autumn they weave expansive webs that bind together the ends of branches. They eat every leaf within reach, continually building larger webs until late autumn, when they pupate. Resembling dirty rags and filled with black droppings and wriggling worms, the webs ruin the aesthetics of any garden.

One way to combat these is to get a long pole and rip the web pocket open in the morning. With the web open, birds throughout the day will feed on the worms.

To plan an effective schedule of prevention and control, it helps to understand the life cycle of Hyphantria cunea. In early spring, moths come fluttering up from cocoons carefully hidden in the bark of tree trunks and in ground debris. The adult moths are about 2 inches from wingtip to wingtip and are white spotted with brown. They lay eggs in clusters on the leaves of suitable host plants.

The eggs hatch within a week. Out come tiny caterpillars, the first generation of the growing season, spinning webs and eating leaves. This first infestation is so mild that sometimes the webs go unnoticed.

The first-generation caterpillars have eaten their fill by early summer. They form cocoons and pupate, usually in the bark, of a tree or underneath leaves or other debris on the ground. By midsummer they re-emerge as moths. A second generation follows -- this time larger and more destructive.

Because the webworms -- in one form or another -- are present year-around, it's possible to devise a year-round strategy for dealing with this pest. Here are some tactics that have worked for me:

* In winter or early spring, remove fallen leaves, ground debris and mulch, which may harbor overwintering webworm pupae. Replace the debris with fresh, pest-free mulch.

* Inspect susceptible plants for the greenish egg masses, which are typically laid on the undersides of leaves and are protected by a woolly or scaly covering. Eggs are deposited from late spring through fall. Remove any affected leaves and destroy them. This strategy requires time and sharp eyes and is obviously impractical for tall trees.

* Bacillus thuringiensis (Bt) is a microbial pesticide that can be applied as a dust or spray. It kills many types of caterpillars but has no effect on warm-blooded animals or bees.

With fall webworms, Bt is effective only if its application is properly timed. Once the caterpillars have enshrouded themselves in webs, they are more difficult to kill. Check on susceptible plants frequently, beginning in late spring, and apply Bt at the first sign of hatching webworms. Bt loses effectiveness after about two days, so it must be reapplied as long as more larvae are hatching.

Always use Bt with care, because it also can kill the larvae of non-pest moths and butterflies.

* When you see webs, clip the infested branches and burn them, or drown the larvae in a bucket of soapy water. A pole pruner with a lopper blade will help you reach webs within 16 feet or so of the ground.

Get your house ready for winter.......now

As a professional home inspector, I see so many homes with problems that could have been avoided with simple home maintenance. Not sure what to look for when determining what items need attention? Why not consider hiring a home inspector to evaluate your home for necessary maintenance tasks? What better person to know what to look for and care for a home that a home inspector? If you can perform your own maintenance, here is a list of fall maintenance items I hope you will find helpful.

Early fall is the best time to start getting your house ready for the cold winter season. Most people don’t get into the winterizing “mode” until the first cold snap, but he reason early fall is better than late fall is because it is just easier to perform some of the different tasks when the temperatures are warmer. Roofing shingles are more pliable and easier to work with, caulk is applied easier when warm and it’s just nicer to work outside when a cold north wind isn’t blowing on your face!

Here is a good checklist for fall maintenance items

1. Clean those gutters
If your house has gutters, be sure to keep them debris free and if you have large trees over the house, you may have to clean them more that once before they lose all their leaves. Many people think, “I’ll just wait until all the leaves fall, then I’ll clean the gutters”. The problem with this is that it does not take many leaves to stop up the drain spouts and if a hard rain comes, water could overflow the gutters and cause water damage to the roof edges and get under the roof’s flashing.

2. Inspect your roof and repair shingles
Perform necessary repairs to cracked and torn shingles. Use roofing cement to seal in areas that you feel may cause leaks and to secure shingles that you may feel will blow off in high winds. Also make sure tree limbs are not touching or rubbing on the roof. Trim any tree branch that may rub on the roof surface. During my routine home inspections, I have seen several roofs that will require expensive repairs simply because tree limbs were rubbing on the roof surface.

3. Cut back shrubs
Shrubs rubbing against the house can invite insects and rodents to enter the house and can cause siding damage when the branches rub on the house in winds.

4. Caulk Windows
By the time the fall rolls around, more that likely your windows probably have cracked caulking around them. Sealing around your windows on the inside as well as the outside of the house can really cut back the amount of cold air that enters your home and warm air that escapes. You may think that these cracks look so small and insignificant, but when you consider all the cracks around all the windows, that could be a lot cold air coming in! Especially pay attention to those north windows.

Here is a tip if you have those older single pane windows with no storm windows installed.

Take some thick clear plastic and cut it to the size of the window frame. Attach it to the inside of the window around the frame and it should create an air space between the glass and the plastic. This will really help insulate the window and keep the room warmer. I have seen people put the plastic directly on the glass, but that will not create the air space. It’s the air space that insulates the window.

5. Clean the fireplace and flue
If your home has a fireplace, make sure it’s clean and clear of creosote buildup before a heavy season of fireplace use. What is creosote? It’s a black flaky substance that builds up in the flue and the opening of the flue. This substance can become flammable in high temperatures, so keep it clean! Also keep in mind that poorly drafted fireplaces can cause carbon monoxide to enter the living space, so always have CO detectors installed in the home when fireplaces are present as well as gas appliances.

6. Winterize external plumbing pipes and fixtures
Don’t wait until the first freeze comes to rush out and do this. Calling a plumber to come out and repair a freeze busted pipe is expensive, not to mention the damage that this can cause. Wrap exposed pipes on the outside of the house and the garage with pipe wrap and install covers on the hose spigots. These are easily removed and reinstalled if you need to use the hose in the meantime.

7. Store outdoor furniture
Most outdoor furniture is made of some sort of plastic material that can crack and break in cold temperatures. If you can’t store it in a protected area, at least wrap the furniture in a thick protective covering.

I hope you find this information useful and again, the best way to get a complete analysis of your home’s condition before the cold weather sets in is to get a professional maintenance home inspection. Call or email me if I can answer any question you may have.