What you need for beetle identification
Anatomy of the ambrosia beetle
Procoxae
Declivity
Scutellum and spatulate hair
The Agriculturally Important Species of
Ambrosia Beetle
Note: Illustrations and sizes are based on female beetles, which commonly are attracted to alcohol-baited traps.
Xylosandrus crassiusculus (Motschulsky)
Granulate Ambrosia Beetle
Procoxae
Separated
Declivity
Hairy, dull and bumpy
Female size
≈ 3 mm in length
Color
Reddish/orange-brown
Scutellum
Flat
Economically important hosts
apples, peaches, pecans, magnolias, and maple
Xylosandrus germanus (Blandford)
Black Stem Borer
Procoxae
Separated
Declivity
Hairy, dull and bumpy
Female size
≈ 3 mm in length
Color
Reddish/orange-brown
Scutellum
Flat
Economically important hosts
apples, magnolias, pecans, pines
Xylosandrus compactus (Eichhoff)
Black Twig Borer
Procoxae
Separated
Declivity
Alternating hair, shiny
Female size
≈ 2 mm in length
Color
Black
Scutellum
Flat
Economically important hosts
apples, magnolias, maples
Xyleborinus saxesenii (Ratzeburg)
Fruit-tree pinhole borer
Procoxae
Contiguous
Declivity
Small spines
Female size
1.9–2.4 mm
Color
Reddish-brown/
black
Scutellum
Conical and hairy
Economically important hosts
apples, peaches, pecans, pines, magnolias, maples
Ambrosiodmus rubricollis (Eichhoff)
Procoxae
Contiguous
Declivity
Hairy, less bumpy than Xylosandrus crassiusculus
Female size
2.4–2.7 mm
Protonum
Entirely bumpy (more than the other species)
Color
Reddish/orange-brown
Scutellum
Flat
Economically important hosts
dogwoods, pecans
Xyleborus spp.
Procoxae
Contiguous
Declivity
Has spines, hairy
Female size
2.0–2.9 mm
Color
Reddish brown
Scutellum
Flat and hairless
Economically important hosts
maples, pines, peaches
Hypothenemus spp.
Procoxae
Separated
Declivity
Spatulate hair
Female size
1–2 mm
Color
Black
Scutellum
Flat
Economically important hosts
apples, magnolias, pecans, pines
Cnestus mutilatus (Blandford)
Camphor Shot Borer
Procoxae
Separated
Declivity
Hairy, dull and bumpy
Female size
Approximately 3 mm in length
Color
Reddish/orange-brown
Scutellum
Flat
Economically important hosts
maples, sweetgums, dogwood, cherry, elm,
golden rain tree, magnolia, oak, and poplar
TRAPPING AND MONITORING
Factors that promote attack
Tree stress promotes attack. Stress may come from the following:
- Frost damage
- Flooding
- Poor soil drainage
- Drought
- Previous injury to tree
- Disease
Bottle trap
Intended use
Insect identification, activity monitoring, and research purposes.
Where to deploy?
Deploy the bottle traps along the wood line as well as inside the nursery/orchard.
When to deploy?
Deploy the bottle traps before the warmer spring weather (when the temperature is approximately 68 °F).
When to check?
Check the bottle traps weekly. Replace the soapy water using a coffee filter and strainer.
Bolt trap
Intended use
Monitoring attacks and ambrosia beetle activity. This trap is recommended for grower use.
Where to deploy?
Deploy the bolt traps along the wood line as well as inside the nursery/orchard.
When to deploy?
Deploy the bolt traps before the warmer spring weather (when the temperature is approximately 68 °F).
What to look for?
Sawdust “toothpicks” and holes.
EXTERNAL INJURY
Sawdust “toothpicks”
Holes
Sap production
INTERNAL INJURY
Tissue discoloration
Gallery formation
Fungus
Different life stages of fungal cultivation can be seen in the following images.
This publication is a collaboration
between the University of Georgia
Cooperative Extension Service,
the USDA Agricultural Research
Service in Ohio, and
Tennessee State University
