Welcome back to the Wonderful World of Weed Man! For those of you who missed last week’s blog, we discussed the Japanese Beetle in our article, ‘Overseas Beetle Invasion!‘ Today, we are continuing our lawn insect series, ‘I Found an Alien in My Lawn!’ with a discussion about Cranberry Girdlers! This is the time of year that we usually begin to see them. We generally do not see a lot of them, they are rare in comparison to other lawn pests. However, they show up just enough to be a nuisance you want to know about. In fact, one of our technicians found this little guy just yesterday:
Repeat after me…..’Cranberry Girdler’ It seems strange to say. It is not a mixed drink, or an appetizer (at least for humans). What is a Cranberry Girdler? Where does it get its funny name? I don’t have cranberries, why are they in my lawn? All legitimate questions.
Cranberry Girdlers are also known as the subterranean web-worm. They are typically a pest of cranberry plants. They like to feast on the plant runners that cranberries spread to obtain water and nutrients. They will remove the bark of the stem and chew on the tissues which will ‘girdle’ the stem. This cuts of the flow of water and nutrients to the plant, which can result in death. It is now obvious how they have acquired their name.
Naming aside, Cranberry Girdlers are not just connoisseurs of the cranberry plant. They also like to feast upon Douglas Fir Trees and many types of cool season grasses as well. Kentucky Bluegrass is a favorite of theirs. Similar to grubs, Adult girdlers will lay several hundred eggs each year in turf grass blades. The larva will feed upon the crown and roots of the grass.
The cranberry girdler will generally only go through one generation per year. Adults emerge, as a moth, in mid-June, and will be active for about 6-8 weeks. The female, after mating, will drop eggs during that time period. Eggs will hatch within 9-11 days and will move down into the upper soil layer of the grass. Once cooler temps in October arrive, the larvae will begin to tunnel deeper into the soil and overwinter until the next year.
The girdler larvae, as they are feeding upon your lawn, will create similar damage to that of the white grub. The lawn will pull up easily since the root system is being digested by the girdler. It will appear from the surface as drought damage or a yellowed area. Typically, most homeowners will realize something isn’t quite right when it does not green up with increased watering.
If you have discovered a Cranberry Girdler in your lawn, it is important to control or eradicate the insect. Otherwise, it can damage your lawn severely when left unchecked. Cranberry Girdlers can be controlled with the following methods:
Natural Predators – Birds eat girdlers! They can actually reduce the population severely by the time fall rolls around. Nevertheless, birds dive-bombing your lawn may not be the best option for a quick or clean solution.
Biological Control – Insect Parasitic Nematodes will combat Cranberry Girdlers. This can be applied via a liquid spray – however it is important to pay attention to application instructions. Nematodes need a very specific environment to be effective. Temperatures too high or too low can influence how effective their performance will be. Water levels in soils are important to be aware of too.
Chemical Control – Most insecticides are safe when applied CORRECTLY. If you are not sure about how to use insecticides safely, please contact a professional for assistance.
There has been a lot of concern about safety when it comes to insecticides. We take safety very seriously when applying treatments on the lawn. Weed Man uses only products for use on home lawns. They are most safely applied in the capable hands of a trained professional like Weed Man. If you have an issue with Cranberry Girdlers, and would like help, please give us a call! www.weedmanboise.com 208-888-9911 #wecareforyourlawn