IMPORTANT AND COMMON INSECTS AFFECTING TWIGS AND BRANCHES

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This category includes a variety of secondary insects, e.g., attacking dead or dying hosts, as well as insects attacking living hosts.


Lepidoptera   Damage is caused by the larvae. The adults are moths.
Northern pitch nodule moth, 

Petrova albicapitana
 
 

Metallic pitch nodule moth,

Petrova metallica

Hosts: Lodgepole pine.  Damage: Larvae feed in pitch nodule, often in twig crotch. May cause breakage. 
Western pine moth, 

Dioryctria cambiicola

Hosts: Lodgepole and ponderosa pine. Damage: Causes pitch masses on twigs and on stems, particularly in association with Cronartium rust cankers. Also infests pine cones.

See also Bark Insects.


 

Coleoptera

Magdalis gentilis Hosts: Pines Damage: Black weevil. The grub-like larvae feed under bark in dead or dying twigs and branches of pines. Adults feed on needles, sometimes causing conspicuous damage
*Various small bark beetles,

e.g. Pityophthorus, Pityokteines, Pityogenes, Phloeosinus

Hosts: Various Damage: Numerous bark beetle species infest slash, and many smaller species are frequently found on twigs and branches. Generally of little concern, but under favourable circumstances mortality may be caused, e.g., western cedar bark beetle, Phloeosinus punctatus, which killed western red cedar on Vancouver Island in 1959. 

 
 
Homoptera   Hemimetabolous insects with sucking mouthparts. A number of species, particularly scale insects, can be of concern, particularly in areas where trees are under stress, e.g., by pollution. Refer to text books for additional information.

 
 
*Giant conifer aphids

Cinara spp. 

Hosts: Conifers  Damage: Feed mostly on twigs and branches. Rarely damaging. Often tended by carpenter ants or other ants. 
Fir mealybug

Puto cupressi

Hosts: Many conifers  Damage: Most damaging on true firs. May reach outbreak status, stunted foliage on subalpine fir. Fluffy masses of white waxy threads cover the females and the clusters of eggs. Can cause mortality of twigs, branches and small trees.