University of Idaho Pest Management Center

above ground symptoms
   - leaf curling & distortion esp. young leaves at center of crown
   - dense colonies on underside of leaves white cast skins from prior generations
   - leaf yellowing, wilting (1st along leaf edges)
   - secrete sticky honeydew black sooty mold

biology:

Life Cycle

winter
eggs on Euonymus & Viburnum
snowball bush, burning bush

spring
2-to-3 generations on winter hosts
initially wingless, asexual females
later winged, asexual females

summer
colonizing flights to summer hosts
     beans, corn, sugarbeets
     lambsquarters, pigweed
explosive, multiple generations
     wingless, asexual females

fall
winged asexual females + winged sexual males
return flights
     from summer crops
     to winter host plants
          Euonymus & Viburnum
1 generation sexual females
     eggs on Euonymus & Viburnum

CONTROL
OPTIONS

strategy:

minimize initial colonization & establishment
slow rate of increase once established

cultural:

biocontrol:

- conserve natural enemies
    (1) recognize common species
          - lady beetle (adult + larva)
          - green lacewing (adult + larva)
          - hover fly
          - parasitic wasps

    (2) manage foliar insecticides
    (3) supplemental foods & habitat for natural enemies
           field border plantings of “insectary plants”
                 alfalfa, buckwheat, clover, mint, vetch
                 (small-flowered, long-blooming plants)
                       - nectar & pollen
                       - additional prey or hosts
                       - insecticide-free refuges
           beneficials recolonize beets after insecticide use

- mass-releases from commercial insectaries

WWW Resources

Biological Control Virtual Info. Center cipm.ncsu.edu/index.html
Suppliers of Beneficial Organisms in N. America www.cdpr.ca.gov/docs/ipminov/bensuppl.htm
Association of Natural Bio-Control Producers
www.anbp.org/

scouting & thresholds:

University of California
- visually inspect individual plants (weekly)
- estimate average % leaf area w/aphids

fig. 1 Black bean aphid scouting

MAY/JUNE	JULY	AUG/SEPT
up to 20% leaf surface with aphids on most leaves	up to 40% leaf area with aphids on all leaves	up to 60% leaf area with aphidsonall leaves

(source: University of California)

Colorado State University
- visually inspect plants in 10-ft row (weekly)
- score (rate) plants as either
infested 4 or more new leaves w/aphids
not-infested < 4 new leaves w/aphids

(source: Colorado State University)

conventional insecticides:

Ecologically selective applications
(1) spot spray aphid infested areas
vs entire field

(2) soil-applied systemic insecticides for aphids
vs foliar-applied contact insecticides

(3) caterpillar stomach poisons
vs contact poisons

Physiologically selective applications
-NO selective aphicides for sugarbeets
vs pymetrozine (Fulfill) for potato aphids

(1) horticultural oil (Concern Spray Oil, Ultra-Fine Oil)
0-day pre-harvest interval
0-day re-entry interval

(2) insecticidal soap (M-Pede and others)
0-day pre-harvest interval
0-day re-entry interval

short residual contact insecticides
- highly effective vs soft-bodied insects
- no control after spray dries

Common name	Trade name	At-plant	Post	Bio- agents	Groundwater
aldicarb	Temik	X	X
diazinon	Diazinon		X
horticultural oil	Concern Ultra-Fine		X
insecticidal soap	M-Pede		X
malathion	Malathion		X
methomyl	Lannate		X
methyl parathion	Declare		X
naled	Dibrom		X
oxydemeton	Metasystox-R		X
phorate	Thimet	X	X
terbufos	Counter	X	X

ALWAYS READ THE LABEL--
THE LABEL ALWAYS TAKES PRECEDENCE OVER ANY RECOMMENDATION

Webmaster:
nbell@uidaho.edu