Aphids

Pest description and crop damage 
Several species of aphid can become problems on broad-leaved trees and shrubs. Their color and size vary with species. All are soft-bodied insects with piercing–sucking mouthparts. They tend to feed in colonies. Aphids feed primarily on succulent tissues. Feeding damage to the plant can be minor to severe. Leaf and shoot distortion can occur if populations are high. Aphids also produce honeydew, a sweet, sticky secretion that collects on plant tissues and encourages growth of black sooty mold. Honeydew is also a nuisance when it falls on decks, cars, or other landscape surfaces and attracts ants, wasps, and bees that feed on this sweet liquid. Some aphids are also vectors of plant diseases, particularly viruses.


Biology and life history 
Most species of aphid have similar life cycles. Aphid females can give birth to live offspring most of the year without mating. Some species of aphid have only one host but commonly aphid species alternate with an overwintering or primary woody host plant then alternate with seasonal host(s).

Aphids usually are found in colonies on new growth, the underside of leaves, and near flower and fruit clusters. Some species have a root aphid stage. In summer and fall, aphid may produce winged females and, later, winged males. They mate and produce eggs for overwintering, especially in colder climates. Otherwise, adult aphid overwinter on crops, weeds, or trees. There may be as few as two generations or as many as 16 generations each year, depending on the species

 

Individual aphid webpages are listed below by host. Click to go to web link.

bamboo - black-spotted bamboo aphid

bamboo - black-spotted bamboo aphid

blue spruce - Cinara aphid

blue spruce - Cinara aphid

cabbage - cabbage aphid

cabbage - cabbage aphid

cherry - black cherry aphid

cherry - black cherry aphid

There are several very nice sites for general aphid information.

 

General info:
Gordon's aphid website
UC Management Guidelines for Aphids

Aphid taxonomy
USDA's Aphidoidea Website

Aphid Identification:

Influential Points.com Aphid Identification
NC State's Key to common greenhouse aphids

Aphid Management or IPM:

Flint, M. 2013. UCIPM Online. Aphids. University of California
ATTRA's Sustainable aphid control for greenhouses

Heteroecious aphids:
Melon or cotton aphid:
NC State's website

Green peach aphid:
University of Florida's Website
NC State's website

Aphids by Hosts:

Conifers:
OSU Extension: Aphid and Adelgid Pests of Conifers

Balsam Fir:
Balsam Twig aphid, Mindarus abietinus
Balsam woolly adelgid, Adelges piceae

Grand Fir:
Balsam Twig aphid, Mindarus abietinus
 

Douglas fir (Psuedotsuga):
Cinara aphids
Ohio State Fact Sheet: Cinara conifer aphids
Cooly spruce gall adelgid, Adelges cooleyi

Pine:
Ohio State Fact Sheet: Cinara conifer aphids
Pine bark adelgid, Pinus strobi
Pine leaf adelgid
White pine aphid

Spruce:
Cinara aphids
Ohio State Fact Sheet: Cinara conifer aphids
Spruce gall adelgids
Spruce aphid, Elatobium abietinum
WSU Agricultural Chemical & Environmental News: Sprucing up your IPM Skills: Plan now to attack spruce aphids next year.

 

Deciduous Trees and Shrubs:

Beech, Fagus:
Woolly beech aphid

Birch, Betula:
PNW Nursery IPM: Birch Aphid

Maples:
Woolly alder aphid
Periphyllus or maple aphid

Perennials:
Chysanthemums
more mums
Foxglove aphid

 

Orginal publication 14 July 2015
Lastest update <24 February 2017>

Author: R.L. Rosetta, Extension Nursery Integrated Pest Management, Department of Horticulture, Oregon State University/NWREC.

Page last modified 2/24/17