Sap Suckers - Aphids & Adelgids
Introduction
 | We are talking about critters from homoptera, hemiptera & arachinidae (spider mites) |
| Homoptera & hemiptera have a gradual life cycle - so you will see varying sizes of 'aphids' and there is no pupal stage |
| Obviously have piercing / sucking mouthparts |
| Feed on plant sap (through foliage or bark) |
| May be mobile or sessile |
| Dispersal may be by active flight or just wind-blown, crawling or passive (by people) |
| Adelgids are on conifers and tend to be covered by a waxy coating or within a gall |
| Aphids are "naked" and can be found on both deciduous & conifers |
| Douglas-fir, balsam and spruce are the most common conifer hosts in BC |
| Damage is typically growth reduction (and mortality) |
| Aphids/Adelgids can have very complex life cycle with many forms and alternating hosts |
| Chemical control for aphids is best at nymph stage when they are most vulnerable (adults often lay over wintering eggs that are tolerant to chemicals) - chemical control for adelgids is challenging because they are covered in wax or 'hiding' in a gall |
General S&S
| discolored foliage (i.e. yellow/chlorotic) - spots or entire needle |
| misshaped foliage (kinked needles, curled foliage) |
| honeydew on leaves (or dropped on vehicles) |
| sooty mold on leaves (mold is eating the honeydew) |
| (fine webbing on foliage - mites) |
| pre-mature leaf drop (perhaps a defense mechanism by plant) |
| branch mortality / top kill / tree mortality |
| galls |
| wooly tufts |
General Control Options
| Biological - parasitic wasps, ladybugs, hover fly/syrphid fly (larva) | ||||
| Cultural - ants "farm" aphids and protect them, so you may have to manage the ants to control the aphids (a.k.a. "kill the ants") - trap the ants | ||||
| Chemical
|
A Few Key Pests
Spruce Aphid (Elatobium abietinum)
| native to coastal BC and eats Ss | ||||||||||
| tend to be active in late winter early spring (hard to find when it gets warm - due to soft body and water loss?) | ||||||||||
| S&S
|
| damage - erratic outbreaks (1981 QCI & outer coast had 5000 ha moderately defoliated); occasionally small areas (<500ha) can suffer mortality (small outbreak in 2006, up to ~600ha in '07, then collapse) | ||||
| mgmt
|
Cooley Spruce Gall Adelgid
| native to BC and indulges on Ss/S and Fd | ||||||||||||||||||||||
| 2 years to return to original host | ||||||||||||||||||||||
| can have many generations/year | ||||||||||||||||||||||
| has 6 "forms" | ||||||||||||||||||||||
| life cycle
| ||||||||||||||||||||||
| S&S
| ||||||||||||||||||||||
| damage
| ||||||||||||||||||||||
| mgmt
|
