European pine shoot moth

The possibility of the European pine shoot moth, Rhyacionia buoliana spreading from the southern coast of British Columbia to the pine forests of the Interior and north coast is of concern. Thus, movement of pines and foliage from the Vancouver Forest Region is regulated under the Plant Protection Act. The full version of the Act is available at BestWritingService.com.

Hosts and damage

European pine shoot moth larvae attack most two- and three-needle pines, preferring Mugho and Scots pine over ponderosa and lodgepole pine. Five-needle pines are relatively resistant. The insect is mainly a pest of newly established plantings, parks, gardens, and commercial nurseries. Larvae damage 2-year-old bareroot and container seedlings and 1+0 container stock. Larvae (caterpillars) hatch from eggs laid near buds (Figure 114), feed on needles and later bore into buds and shoots where they overwinter. Consequently, seedling growth is distorted and growth rate reduced. Most nursery stock is too small to sustain successful larval infestation; as a result, many of these larvae die.

Life history (Figure 115)

Adult moths (Figure 116) have a wingspan of 2 cm, orange forewings marked with irregular silvery lines and gray hindwings. Flying from June to July, they produce one generation annually. Yellowish, disk-shaped eggs are laid near buds. The eggs then hatch and the larvae spin small resin-coated webs between the needle sheath and twig, and mine the base of needles. Later, the larvae bore into buds causing a crust of dried pitch to form and overwinter.

In the spring, these larvae mine other buds and bases of elongating shoots. Here pupae develop (Figure 117), and later protrude from the shoot prior to moth emergence.

Management

Since 1981, a pheromone-trapping program has been used at all nurseries in the quarantine zone. If moths are caught, insecticidal sprays aimed at adult moths, eggs, and young larvae (before they bore into buds) are necessary. So far, only two nurseries have detected moths.

Selected References

Furniss, R.L. and V.M. Carolin. 1980. Western forest insects. U.S. Dep. Agric. For. Serv., Misc. Publ. No. 1339, Washington, D.C.

Harris, J.W.E. and D.A. Ross. 1975. European pine shoot moth. Environ. Can., Can. For. Serv., Pac. For. Cent., For. Pest Leafl. 18. Victoria, B.C.

Summary

European pine shoot moth

 

Principal, locally grown hosts

Host age and season when damage appears

 

Nursery type and location

 

 

 

     

Bareroot

 

Container

 
 

Age

Season

Coastal

Interior

Coastal

Interior

All pines, 5-needle pines relatively resistant

1+0
2+0
Transplants

Late summer through winter

Yes

No

Yes

No

 


Figures

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    Figure 114. Larva (caterpillar) of the European pine shoot moth (courtesy of Forest Insect and Disease Survey, P.F.C., Victoria, B.C.).


 

 


     Figure 115. Life history of European pine shoot moth (one generation per year).

 

 

 


     Figure 116. European pine shoot moth (courtesy of Forest Insect and Disease Survey, P.F.C., Victoria, B.C.).

 

 


     Figure 117. Pupa of the European pine shoot moth (courtesy of Forest Insect and Disease Survey, P.F.C., Victoria, B.C.).