What is this grub eating my poor roots!

Asked April 22, 2018, 10:59 PM EDT

Grass took over my garden bed, I removed the grass to find this chubby monster. I remember my mom saying they eat root... what is he and how do I kill him without hurting the worms? I don’t believe he has legs at least none I see. Seems so wriggle to move not inch or crawl.

Washington County Oregon snails crane fly leatherjackets

3 Responses

Thank you for the excellent images.

The critter on your palm is a crane fly larvae. Even though they may be found in the soil of both lawns and garden beds, they are seldom a significant problem. You can dispatch them as you find them – putting them in slightly soapy water works well.

I am a bit more concerned about identifying the snails in the white pan. They look suspiciously like brown garden snails, Cantareus aspersus, formerly Helix aspersa. Invasive creatures which eat a wide variety of garden plants, both ornamental and edible. “Snails and Slugs” describes these snails and discusses management in home gardens. (http://ipm.ucanr.edu/QT/snailsslugscard.html ) If you have any questions as to the correct ID for the snails in your image, please send me close-ups of both sides of the shells.

I've posted an image of the brown garden snail with this email. (Photo by Jack Kelly Clark.)






I’m not as worried about the snails as I have put copper strips on the edges of my raised garden. And as there is nothing in it right now I fluffed the soil with some cow manure and raised bed soil after removing all weeds, than sprinkled it with sluggo. But the Crain fly larve seem to be heavy in the soil. I’m worried if I plant I’m risking the new plants health. How do I get rid of them without getting rid of any essential bugs like worms?

In spite of the rumors you may have heard, crane fly larvae (leatherjackets) are seldom a problem in gardens.

To be blunt, my 35 years of experience with brown garden snails (in Southern California) tells me you should worry about them.

Copper strips can exclude snails from a garden but only if the bands are 4-inches wide. Another requirement is make certain that plant materials don’t create easy “snail highways” into the garden area by flopping over the edge.

If the leatherjackets were in a lawn, the level to begin treatment is 50 per square foot. How many do you have?