Urban IPM

Friday, July 24, 2015

Seasonal Crickets

Prepare thy-selves people of Central Texas.....they are coming.  I've seen immature crickets around various buildings in Central Texas.  The adult masses are building.

Crickets are about 1" long, dark brown to black with large hind legs used for jumping.  Female crickets have a large, sword-like structure, the ovipositor, protruding from the tip of the abdomen.
The ovipositor is an egg laying structure.

Cricket nymph.

Crickets feed on plant material and other insects.  They can cause damage to seedlings and be destructive to plants when in high numbers.  Males can become a nuisance with their sounds (there's always that one cricket chirping at night when you're trying to sleep).  Crickets can further become a nuisance when masses of them flock to lights at night or when piles of dead crickets form near doorways and other areas, causing a foul odor.

Cricket management is more easily accomplished in the summer months when nymphs, who cannot fly, are present (this is why I am writing this now!).  Most people do not try to do anything about crickets until they are in the adult stage and in large numbers.

Before crickets invade your home try some of the following tips:

  • Turn off lights at night, direct lighting away from the structure or use yellow bulbs which are less attractive to insects
  • Seal cracks and crevices that give entrance to the structure with sealant
  • Remove debris that is stacked near the structure
  • Keep lawn and surrounding landscape tended
  • Stuff weep holes with copper mesh (this will allow air flow into the wall voids, but will reduce accessibility)

Friday, July 10, 2015

Cicada killers

Cicada exoskeleton.
Have you seen any cicada exoskeletons (they look like Garthim from Jim Henson's The Dark Crystal) lately? I found one near my front porch last week.  This time of year, with the cicadas (and their noise) come the topic of today's post- cicada killers.  These large wasps can be startling to see when they fly around trees or low over the lawn.  They reach about 1.5 inches in length with dusky wings, reddish-brown thorax and a yellow and black abdomen.

Cicada killer wasp.
Females are pretty docile, but males are territorial and will fly at you until you leave their area.  Only female wasps (and bees) can sting as the stinger is a modified egg-laying structure.  The female cicada killers create burrows in the ground and then go off to sting cicadas.  The cicadas are paralyzed by the sting and taken by the wasp back to the burrow where she digs a side tunnel, crams in the cicada and lays an egg on it.  When the egg hatches, it will feed on the cicada provided.

That being said, cicada killers can be considered beneficial as they help to cut down on the cicada population.  They can also be considered a pest since sometimes people will have holes all over the yard from the wasps' tunneling behavior.  If you fall into the latter category and want to do something to manage the population, you can sprinkle a insecticidal dust over the holes and tamp it down with your shoe.

Friday, June 26, 2015

Squash Vine Borer

My neighbor asked me why her squash seemingly died overnight. Unfortunately, I had to tell her about squash vine borers (SVB). If you grow squash in Central Texas, you are most likely familiar with this insect and it's damage. If you have not yet had the pleasure of encountering SVB, either lucky you or welcome to Texas or welcome to vegetable gardening!

Squash vine borer refers to a moth that lays reddish-brown eggs singly on the base of squash plants. When the eggs hatch, the larvae bore into the squash stem where they feed on the plant from the inside. So if the insect is on the inside of the plant, how can you tell if that's the problem? Typically, there is a hole in the stem where the larvae entered which has yellow sawdust-like frass coming out of it. Larvae overwinter in the soil, pupate, then emerge as adults in the spring to mate and lay eggs. Adult moths are about half an inch long with bright, contrasting colors. The abdomen is bright orange with black dots. The front wings are a greenish-black color and the hind wings are clear, but you typically don't see the hind wings as the wings are folded over the back when at rest.  Damage is death of the squash vine.  Usually it starts at the base of the plant and moves towards the outer parts.

If you have had squash vine borers infest your squash, vines should be removed and destroyed (not composted unless you are sure your compost pile temperature reaches high enough to kill insects) soon after squash harvest. Soil can be tilled before planting to reduce the number of larvae that are in the soil. Row cover can be used to protect new crops of squash you may plant, just remember to remove the row cover when the squash has blooms to allow pollination to occur (or hand pollinate). If you leave the squash uncovered, monitor the stems regularly for eggs and squish the eggs before larvae emerge.
You can also try to remove the borer from the stem before too much damage occurs if you catch the infestation early enough. Slit the stem lengthwise with a sharp knife, remove the borer and then cover the cut stem with moist soil and hope it takes root.  Some people may have better luck with squash varieties that root wherever they touch the ground.
On another note, have you been tuning in for the All Bugs Good And Bad FREE webinar series? If you missed one (or all for that matter), you can still listen and get great information!
Here's a link to all of the webinars for 2015.
For the webinars that have already occurred, you can click on the topic you are interested in learning more about and it will load that presentation page. At the top right corner there is a "watch recording" button. Click on that and you will be able to listen to the webinar.