UCCE Master Gardeners of San Joaquin County
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UCCE Master Gardeners of San Joaquin County

Posts Tagged: thousand cankers disease

Jackson Audley: A Case Study with the Walnut Twig Beetle

The walnut twig beetle is about the size of a grain of rice. (Photo by Kathy Keatley Garvey)

So tiny and so destructive. It's about the size of a grain of rice but it's a killer. That's the walnut twig beetle, Pityophthorus juglandis, which in association with a newly described fungus, Geosmithia morbida, causes thousand cankers disease,...

The walnut twig beetle is about the size of a grain of rice. (Photo by Kathy Keatley Garvey)
The walnut twig beetle is about the size of a grain of rice. (Photo by Kathy Keatley Garvey)

The walnut twig beetle is about the size of a grain of rice. (Photo by Kathy Keatley Garvey)

Invasive Pest Spotlight: Ambrosia Beetles

Male (left) and female walnut twig beetles. [L. Strand]

Today's post for National Invasive Species Week highlights two ambrosia beetles that are detrimental to certain trees. Ambrosia beetles are highly specialized beetles that excavate tunnels in usually weakened or dead trees and cultivate fungal gardens,...

Posted on Wednesday, February 24, 2016 at 10:36 AM
Tags: ambrosia (1), beetles (13), borer (4), fungus (4), fusarium (4), invasive species week (5), pest (75), polyphagous (4), PSHB (3), thousand cankers disease (4), UC IPM (225), walnut twig (2)

Killer in Our Midst

Walnut Twig Beetle

There's a killer in our midst, and a chemical ecologist will tell us all about it. The killer: thousand cankers disease. The victim: native black walnuts. The speaker: Steve Seybold. Seybold (right), a research entomologist with the Chemical Ecology of...

Walnut Twig Beetle
Walnut Twig Beetle

WALNUT TWIG BEETLE, in association with a newly described fungus, can fell a mighty black walnut tree. This photo shows how tiny it is--it's smaller than a grain of rice. (Photo by Kathy Keatley Garvey)

Posted on Monday, May 17, 2010 at 6:48 PM

A One-Two Punch

Tiny walnut twig beetle

When you look at the tiny unassuming walnut twig beetle--it's smaller than a grain of rice--you wonder how it could possibily kill a majestic black walnut tree. By itself, it can't.  But when it's associated with a...

Tiny walnut twig beetle
Tiny walnut twig beetle

WALNUT TWIG BEETLE is smaller than a grain of rice. (Photo by Kathy Keatley Garvey)

Death and destruction
Death and destruction

DYING walnut trees in Davis, Calif., the result of "The Thousand Cankers Disease," caused by a tiny walnut twig beetle in association with an unknown fungus in the genus Geosmithia. (Photo by Steve Seybold)

Posted on Thursday, July 2, 2009 at 6:16 PM
 
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