Cranberry Girdler Flashcards
Please Read
https://www.for.gov.bc.ca/hfd/pubs/docs/Frr/Frr065.pdf
Where is the CG a problem
Seedling Nurseries
What species does CG prefer
Douglas-fir, True firs and some Spruce
Where, geographically, are seedlings most at risk?
Both Interior and Coastal nurseries are susceptible to CG attack
What kind of seedling stock does CG target?
Mostly bare-root stock, and some container stock
Where, geographically, is the container stock susceptible?
Interior
What part of the seedling does CG attack?
The bark and wood of the stem, 2.5cm above and below soil.
Are there any other parts of the seedling that CG feeds on?
Some root damage may occur with CG feeding.
What are the Symptoms of CG?
Seedlings become chlorotic, unless feeding takes place later in the growing season.
What is the extent of the area that CG can affect?
A single larva can feed on up to 5 seedlings. Making the attack rate very patchy throughout the nursery.
When can the damage be noticed?
Usually not until the seedlings have been lifted.
How far can CG travel to new seedlings between feedings?
Once CG has fed on about 5 seedlings, they can travel up to 50cm to reach new ones.
When does most damage occur?
During August, but may be as late as October
Where does CG go in Autumn?
Form cocoons in the soil at the base of the seedlings
What does CG larva look like?
1.5 cm long, tan head and “dirty-white” coloured body, covered in long and short hairs
What is the management technique for CG?
Use pheromone traps
What is the density of traps used in Nurseries?
1 trap every 30m in bare root nurseries and 1 trap per greenhouse
When are the traps used?
Early June to mid-August
When is peak flight time for the adult moth?
Mid-June to mid-July
How many moths need to be caught before suppression methods take place?
3 moths within any given week caught in the pheromone traps
If 3 moths are caught within 1 week, what is this an indicator for?
Damage to seedlings will be high the following year from the larvae.
What is the management technique for CG?
A single insecticidal spray is used.
How does this spray affect CG?
Acts as a repellant and kills moths that come into contact with it.
