pest management – Maryland Grows

Termites and Carpenter Ants: How to Tell the Difference

September 25, 2024September 25, 2024Maryland GrowsLeave a comment

Wood-damaging insect pests are a concern for anyone who lives in a structure made of wood. So it’s not surprising that we get several samples of insects for identification at our county offices.

Pests can damage wood by eating, excavating, or using it for their homes or galleries. Damage to foundational components can be especially alarming and expensive to fix.

Q. What are some physical differences between a carpenter ant and a termite that can be seen with the naked eye?

Antennae – straight or elbowed?
- Ants have elbowed antennae
- Termites have straight antennae
Wing length – same length or is the front set longer?
- Winged termites have wings that are much longer than the body and are of equal length
- Winged ants have wings of different lengths

Pinched or narrow waist versus one long segment?
- Ants have a narrow or pinched waist
- Termites have bodies that are all the same width

a diagram comparing a termite and an ant — *Comparing a termite (top) to an ant (bottom). Diagram courtesy of USDA Forest Service Archive, USDA Forest Service, Bugwood.org*

a carpenter ant female — *Black carpenter ant (Camponotus pennsylvanicus), winged queen. Photo: Jon Yuschock, Bugwood.org*. Note the narrow or pinched “waist.”

Q. Is there a difference in the damage caused by carpenter ants and termites?

Yes. Both can compromise the structural integrity of a building but the actual damage is going to be different. Carpenter ants make galleries and excavate damp or moisture-compromised lumber to make their colonies. Termites eat the lumber and live in tunnels that they make.

Q. What are the similarities between termites and carpenter ants?

Both are social insects that live in large complex colonies.
Both carpenter ants and termites are attracted to moisture, so be sure to fix any drainage issues that would create a wet environment.

Q. Does landscape mulch lead to termites in your home?

The short answer is no; however, mulched areas may be more attractive to termite activity because of the increased moisture.

Here are some suggestions for protecting your home offered by the University of Kentucky.

Try to prevent the wooden foundation from coming into direct contact with the soil. Also, prevent tree limbs from touching your roof, as this gives insects an easy pathway from the soil to your home.
Do not let moisture accumulate near the foundation. Divert drains and downspouts away from the foundation, as well as lawn sprinkler or other irrigation systems.
Reduce and eliminate excess moisture and humidity around the foundation of your home including both basements or crawl spaces.
Never store firewood or debris against foundations or inside the home.
Use mulch sparingly, especially up against the foundation.

If you are looking for information on how to treat or prevent termite infestations, Mississippi State University Extension has all the details in its Methods of Termite Control.

Remember that both these insects can be nuisance pests when they invade your home or other buildings; however, in nature, they are responsible for helping to break down stumps, fallen trees, and other debris. They also serve as a valuable protein source for birds and other small carnivores. So when possible, appreciate the value that they bring to your local ecosystem and food web.

For all the details on termites and carpenter ants, visit the Home and Garden Information Center webpage.

By Ashley Bodkins, Senior Agent Associate and Master Gardener Coordinator, Garrett County, Maryland. Read more posts by Ashley.

Scary Bugs (And Why You Shouldn’t Be Afraid)

June 28, 2024June 27, 2024Maryland GrowsLeave a comment

Eek! It’s a bug!

I know most folks don’t like creepy-crawlies. Bugs aren’t their thing. Mine, yes, but this is what I do – help people deal with garden pests and protect good bugs.

Some good guys do look scary, like something out of a sci-fi movie with spikes and fangs and ridges and crazy colors.

But looks aren’t everything. In most cases, these are good bugs – what we call beneficial insects – that help to control the few bad dudes in your garden.

Let me introduce you to a few bug friends that aren’t beauties but do a beautiful job of controlling harmful pests.

Assassin bugs get a bad rap simply because of their name. We’re talking James Bond, right?

an assassin bug is a cloudy-gray color with a hump on its back — *Scary-looking assassin bugs are efficient predators. Photo: Photo: Johnny N. Dell, Bugwood.org*

That’s a good thing. Assassin bugs are efficient predators, but boy, do they look scary. Battleship grey with spikes down their backs, they look like they’re wearing armor.

But the battle is mostly one-sided. Insects that cross an assassin bug’s path likely will get skewered by its lance-like mouthpart and slurped dry.

Stop shuddering. There’s an upside.

Assassin bugs eat almost any bug, making them ecological balancers that keep insect populations in check. Plus, they enjoy snacking on Japanese beetles, the scourge of many a garden.

Cute and beneficial, the ladybug lies at the other end of the beauty spectrum. But as youngsters, ladybugs resemble tiny orange and black alligators which often get squished because they look like they are Up To No Good.

a lady bug larva is black and organge and resembles a miniature alligator — *Spiky ladybug larvae control aphids and other pests. Photo: Whitney Cranshaw, Colorado State University, Bugwood.org*

Not true. These are good guys who consume even more aphids, spider mites, scales, and other baddies than adult ladybugs. In fact, one ladybug can eat over 5,000 aphids in its lifetime.

Many juvenile insects look nothing like their more familiar adult counterparts. So stop before you squish or spray. Snap a photo or bring a sample to your local Extension office. Most likely it’s an ally you want to protect.

You can find your Maryland Extension office on our website. Or reach out to the certified horticulturists at our Home & Garden Information Center for help. Send a photo or question to them at Ask Extension.

Wasps get a bad rap, too, with much swatting and shrieking and fear of The Stinger. Only females have those – they’re modified egg-laying organs – and they aren’t likely to use them unless threatened.

But most wasps are beneficial, preying on bad bugs or laying their eggs on them to feed their young. Plus, they are pollinators, protecting 1 in 3 bites of food we eat.

a wasp visiting a white-flowering plant — *Scoliid wasps lay their eggs on Japanese beetle larva. Photo: Shanon Wolf*

Spiders aren’t insects – they have 8 legs, not 6 – but they give many people the willies. But spiders also are beneficial, quietly and efficiently consuming many harmful insects.

a black and yellow garden spider in its web — *Argiope spiders provide free pest control in the garden. Photo: Heather Lawhead*

Beauty isn’t everything. An army of not-so-lovely-but-useful insects are your allies in the garden, protecting your plants from the 1 in 10 bugs that are actually harmful.

So think before you squish or spray. Get us a photo or sample. We’ll identify it and give you management tips that deal swiftly with bad bugs while protecting beneficial insects.

By Annette Cormany, Principal Agent Associate and Master Gardener Coordinator, Washington County, University of Maryland Extension.

This article was previously published by Herald-Mail Media. Read more by Annette.

Vegetable Problems Update

July 21, 2023August 4, 2023Maryland Grows2 Comments

Wildfire smoke

Persistent wildfire smoke is new for Maryland gardeners. Experts seem to agree that smoke and ash do not pose a health risk for garden produce. Smoke diffuses sunlight but will probably not significantly reduce the total amount of light for photosynthesis. We have not heard/seen any reports of gardeners picking up smoky flavors in harvested greens or other vegetables or fruits.

Wash all produce prior to eating it raw or cooking with it
Wear an N-95 quality mask when working outside on days when wildfire smoke worsens air quality
Hose off plants if a noticeable soot layer develops from prolonged, intense smoke

Wildfire smoke has been shown to boost the levels of ozone and other air pollutants which can injure plants. Watermelon, squash, pumpkin, beans, and potato are especially vulnerable to high ozone levels (above 75 ppb).

Drought and damaging storms

Wildfire smoke interfered with weather patterns and likely contributed to cooler and drier weather across much of the state.

Mid-May through June:

Lower average temperatures
75% of state in moderate drought on July 3rd
Slow start for warm-season crops

July:

High heat and humidity
Spotty rainfall
Insect and disease issues increasing

Maryland drought status map — The Maryland Department of the Environment announced a Drought Watch on July 10, encouraging voluntary reduction in residential water use.

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Biological pest control: parasitoids

August 10, 2022August 11, 2022Maryland Grows5 Comments

¿Hablas español? Aquí esta una traducción: Control biológico de plagas: los parasitoides

Parasitoids are natural enemies of pests that, like predators (ladybugs and flower flies) can help us keep pest populations at bay or eliminate them from our gardens.

Parasitoid or parasite? Let’s learn the difference between these terms

Before saying more about this group of natural enemies, let me tell you that it is very common to confuse the term “parasitoid” with the term “parasite.” Parasites and parasitoids have in common the need for a host for their development. The difference between the two types of organisms is that parasitoids kill their host to complete their life cycle. That is, the parasite can live at the expense of the host without having to kill it, while the parasitoid ends up killing its host upon completion of its life cycle. Parasites are generally known to be annoying and even transmit diseases to animals, plants, and humans, while parasitoids are beneficial insects, as they help us control pests.

What is a parasitoid?

Parasitoids are insects that insert their eggs into the body or egg of another insect (host) in order to complete their life cycle. Parasitoids go through complete metamorphosis, four different stages of development: egg, larva, pupa, and adult. To finish their development, the parasitoids must feed on their host, and the females first deposit their eggs in their host. As soon as the parasitoid egg hatches, the larvae begin to devour the tissues of their host. Once the larvae reach a certain size, they become pupae, after which the adult emerges, killing the host.

Parasitoids can be classified according to their oviposition (egg-laying) behavior. Endoparasitoids are the parasitoids that lay their eggs inside the body or egg of their host. In contrast, ectoparasitoids oviposit on top of the body of their host, that is, on the surface of their body. To see these fascinating creatures in action you can, watch a video of endoparasitoids and one of ectoparasitoid activity.

Life cycle of an ectoparasitoid (adapted from Presa-Barra et al 2020)

Life cycle of an endoparasitoid (adapted from Presa-Barra et al 2020)

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Essential Oils for Mosquito Control

May 14, 2018April 3, 2023Maryland Grows5 Comments

Mosquito season is here, and many people turn to essential oils for mosquito control as a way of avoiding synthetic insecticides, but this is often met with a mixture of success.

The Asian tiger mosquito, *Aedes albopictus*, is an aggressive daytime feeder commonly found in urban and suburban areas. Photo by Susan Ellis, Bugwood.org

The Environmental Protection Agency (EPA) considered essential oils to be minimum risk pesticides, so there is no testing being done on their effectiveness before they go to market, which allows for a wide range of products to be sold that may not work. While there is a growing interest in the use of essential oils as possible methods for controlling mosquitoes, most of these studies are focusing on how essential oils can be used when applied to the skin or fabric as a repellent rather than as a yard barrier spray. Garlic oil, Lemongrass oil, and Citronella oil are commonly used essential oils in barrier sprays, but there is little to no research on them showing their effectiveness on mosquitoes in the United States.

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