japanese beetles 101: myth busters: japanese beetle ......§many myths, misunderstandings, and...
TRANSCRIPT
2/7/20
1
University of Wisconsin: Insect Diagnostic Lab
Japanese Beetles 101: An In-Depth Look at a Top Yard &
Garden PestPJ Liesch
UW-Insect Diagnostic [email protected]
Twitter: @WiBugGuy
insectlab.russell.wisc.edu
1
University of Wisconsin: Insect Diagnostic Lab
Myth Busters: Japanese Beetle Edition
!
§ Many myths, misunderstandings, and misconceptions exist regarding Japanese beetles and their management
§ This icon will cue you in on important items
2
University of Wisconsin: Insect Diagnostic Lab
Japanese Beetle: Popillia japonica§ Non-native scarab beetle from Japan
§ Feeds on 300+ types of plants; highly destructive pest
§ Estimated to cause > $450 Million in damage each year
Photo Credit: Joseph Berger, Bugwood.org
Japanese Beetle
Photo Credit: Jon Yuschock, Bugwood.org
Multicolored Asian Lady Beetle
!
3
University of Wisconsin: Insect Diagnostic Lab
Native Range of Japanese beetle
Map Credit: Google Maps
Honshu
Hokkaido
5
University of Wisconsin: Insect Diagnostic Lab
North American Arrival§ Discovered in Riverton, NJ in
August of 1916
§ Accidentally introduced to local nursery ~5-6 years earlier with Japanese irises
§ Plant Quarantine Act 1912§ Regulated import of plant goods§ Nursery stock inspections by USDA Map Credit:
Google Maps!
6
University of Wisconsin: Insect Diagnostic Lab
Estimated Early Spread in US:Washington
Oregon
Montana
California
Arizona
Wyoming
Nevada
Idaho
UtahColorado
NewMexico
Texas
Oklahoma
NorthDakota
SouthDakota
Nebraska
Kansas
Louisiana
Arkansas
Missouri
Iowa
Minnesota
Wisconsin
IllinoisIndiana
Michigan
Ohio
Kentucky
Tennessee
Florida
MississippiAlabama
Georgia
SouthCarolina
NorthCarolina
Virginia
WestVirginia
Pennsylvania
Maryland
NewYork
Maine
Delaware
NewJersey
Vermont
NewHampshire
Massachusetts
Connecticut RhodeIsland
191619201926193219331937194119421944194619511952
7
2/7/20
2
University of Wisconsin: Insect Diagnostic Lab
Why Have Japanese Beetles Thrived Here?
§ Come from similar latitudes in native range
§ Feed on an extremely broad range of plants
§ Mobile and relatively long-lived
§ Easily transported (both larvae and adults)
8
University of Wisconsin: Insect Diagnostic Lab
Current Distribution in US
Map Credit: USDA
Temperature & soil moisture influence the distribution of the JB
9
University of Wisconsin: Insect Diagnostic Lab
Distribution in Wisconsin
Map Credit: Google Maps
§ Well established in southern WI§ Can occur in pockets
§ Gaining footholds in northern WI
10
University of Wisconsin: Insect Diagnostic Lab
Life Cycle
Photo Credit: University of Nebraska Lincoln
11
University of Wisconsin: Insect Diagnostic Lab
Eggs§ Female will lay 40-60 eggs throughout her lifespan
§ Burrow into soil 12+ times over lifetime to lay individual eggs
§ Egg laying influenced by:§ Nearby food plants (adults)§ Preferred groundcover§ Soil conditions
§ Eggs hatch in 10-14 daysPhoto Credit: Glen Obear, UW-Entomology
Egg laying tunnel
Photo credit: David Cappaert, forestryimages.org
Eggs
12
University of Wisconsin: Insect Diagnostic Lab
Drawing credit: USDA Technical Bulletin No. 1449
Raster Pattern
Larvae (White Grubs)
§ Pale C-shaped grubs§ Orange/brown head capsule§ 3 Pairs of jointed legs
§ Soil-dwelling; feed on plant roots§ Upper ~2” of soil
§ Pass through 3 stages (instars)
§ Overwinter as 2nd/3rd instars
Photo credit: David Cappaert, Bugwood.org
White Grub
Photo credit: UW-Entomology
1st, 2nd & 3rd Instar Grubs
13
2/7/20
3
University of Wisconsin: Insect Diagnostic Lab
Winter:
15˚C59˚F
10˚C50˚F
10˚C50˚F
15
University of Wisconsin: Insect Diagnostic Lab
Influence of Winter Weather
§ Cold temperatures can kill Japanese beetles§ Supercooling point of -7˚C (19˚F)
§ Snow cover has a great influence!
§ Influence of polar vortex?§ 2014§ 2019
Photo Credit: PJ Liesch, UW Entomology
16
University of Wisconsin: Insect Diagnostic Lab
Life Cycle
Photo Credit: University of Nebraska Lincoln
17
University of Wisconsin: Insect Diagnostic Lab
Pupae§ Grubs create a small cell in soil to pupate
§ “Inactive” life stage§ Not moving or feeding
Photo Credit: USDA-APHIS
§ Undergoing dramatic transformation to adult beetles§ 1-2+ weeks
§ New adults remain in earthen cell for up to 2 weeks
Japanese Beetle Pupa
18
University of Wisconsin: Insect Diagnostic Lab
Adult Japanese Beetles§ Size: 3/8” long
§ Females slightly larger
§ Hard exoskeleton; 3 pairs legs
§ Color: Metallic green w/white spots along sides
§ Coppery-brown wingcovers
§ Live for 4-6 weeksPhoto credit: David Cappaert, Bugwood.org
Japanese Beetle Adult
Drawing credit: USDA Technical Bulletin No. 1449
Adult Forelegs
19
University of Wisconsin: Insect Diagnostic Lab
Courtship on Six Legs§ Unmated females produce
potent pheromone
§ Males emerge before females
§ Initial mating: “balling”
§ Males mate w/multiple females
§ Females mate multiple times during her life
§ Females will feed while mating
Photo Credit: C Watts, Via Flickr
Photo Credit: PJ Liesch, UW-Entomology
20
2/7/20
4
University of Wisconsin: Insect Diagnostic Lab
Adult Behavior: Flight§ Flight influenced by environmental conditions:
§ Need temperatures to be ~70˚+ F to fly
§ Stop flying above 95˚F
§ Increased flight on clear, sunny days with light wind
§ Decreased flight on cool/windy days, cloudy days, rainy days
Photo Credit: Jon Yuschock, Bugwood.org
22
University of Wisconsin: Insect Diagnostic Lab
Adult Behavior: Feeding§ Feeding also influenced by environmental conditions:
§ Peak feeding: mid-morning to late-afternoon§ Prefer sunny areas / parts of plants§ Feed at top of plant first
Photo Credit: William Fountain, Bugwood.org Photo Credit: William Fountain, Bugwood.org
23
University of Wisconsin: Insect Diagnostic Lab
Adult Behavior: Aggregation§ Japanese beetles do not have an aggregation pheromone
§ Aggregation due to “blood in the water” phenomenon
§ Plants release volatile chemicals which attract beetles§ Injured plants release greater amounts of volatiles
Photo Credit: M.G. Klein, USDA Agricultural Research Service, Bugwood.org
!
24
University of Wisconsin: Insect Diagnostic Lab
Host Plant Feeding Range§ Known to feed on 300+ species from 79 plant families!
§ Landscape trees:§ Lindens, maples, birches, crabapple, elms, mountain ash
§ Landscape shrubs & flowers:§ Roses, euonymus, alders, zinnias, milkweeds, geraniums
§ Fruits:§ Apples, stone fruit, raspberries, grapes, strawberries, etc.
§ Vegetables & other garden crops:§ Beans, corn, asparagus, herbs, etc.
25
University of Wisconsin: Insect Diagnostic Lab
Feeding Damage
§ Mouthpart anatomy dictates plant damage
Photo Credit: Pest and Diseases Image Library, Bugwood.org
Photo Credit: Iowa State Entomology
Adult
Larva
26
University of Wisconsin: Insect Diagnostic Lab
Adult Plant Damage
Photo Credit: Steven Katovich, Bugwood.org
Photo Credit: Steven Katovich, Bugwood.org
§ Skeletonization
§ Bronzing
27
2/7/20
5
University of Wisconsin: Insect Diagnostic Lab
Adult Plant Damage
Photo Credit: Whitney Cranshaw, Bugwood.org
Photo Credit: European and Mediterranean Plant Protection Organization, Bugwood.org
Photo Credit: Daren Mueller, Bugwood.org
28
University of Wisconsin: Insect Diagnostic Lab
Grub Damage§ Soil dwelling grubs chew on plant roots
§ Damaged turf results in irregular brownish patches
§ Severely damage turf can be rolled back like a rug
Photo Credit: M.G. Klein, Bugwood.org
§ A healthy lawn can tolerate some grubs (~10 grubs / square ft)
§ Foraging animals can cause additional damage
29
University of Wisconsin: Insect Diagnostic Lab
Dealing with Japanese Beetles & Their Damage
Management Scenarios:1. Turfgrass2. “Small” plants (gardens, flowers, shrubs, small trees)3. “Large” plants (trees)
§ Many factors can influence management approaches:§ How much free time you have?§ How many plants are affected and how big are they?§ How large of an area?§ Personal preferences—aesthetics, organic, etc.
30
University of Wisconsin: Insect Diagnostic Lab
Management Approaches
Cultural Manipulation of the local environment to reduce pest populations or damage
Physical Physical activities performed to help prevent or reduce pests
Biological Use of natural enemies to reduce pest levels (i.e., predators, parasites, pathogens)
ChemicalUse of pesticides to reduce pest levels; this can include conventional, organic, and biopesticide options
31
University of Wisconsin: Insect Diagnostic Lab
IPM Pyramid
Cultural Practices
Physical/Mechanical Control
BiologicalControl
ChemicalControl
Prevention
Intervention
32
University of Wisconsin: Insect Diagnostic Lab
§ Manipulation of the local environment to prevent pest problems or reduce the amount of damage
§ Plant location in the landscape§ Choosing less-preferred plants§ Lawn care§ Tolerance
Cultural Practices
33
2/7/20
6
University of Wisconsin: Insect Diagnostic Lab
Lawn Care:§ Good general lawn care practices help (fertility, etc.)
§ Fertilizing in fall may help increase tolerance
§ Mow at a higher setting; have sharp mower blades
§ Modify irrigation practices
34
University of Wisconsin: Insect Diagnostic Lab
Tolerance:§ Varies from person to person with individual preferences for
aesthetic factors
§ Healthy turf can tolerate 10+ grubs/sq ft; re-seed if needed
§ Healthy trees/shrubs usually tolerate occasional defoliation
§ Many plants put out an overabundance of leaves; moderate feeding damage can have minimal impacts
35
University of Wisconsin: Insect Diagnostic Lab
Physical Control§ Physical activities performed to help prevent or
reduce pests
§ Hand-picking § Squishing § Barriers/row cover§ Traps
36
University of Wisconsin: Insect Diagnostic Lab
Hand-Picking & Squishing§ Must be done regularly to maximize effectiveness
§ Limited by amount of free time & size / number of plants§ No residual protection
§ Defensive behavior: fly or drop to ground
Photo Credit: Whitney Cranshaw, Bugwood.org
§ OK to dump in yard when done?§ Yes! !
37
University of Wisconsin: Insect Diagnostic Lab
Can manual removal make a difference? § Yes!—especially early in season before significant damage
occurs
§ Picking beetles even once a day in late afternoon or early evening can make a difference
38
University of Wisconsin: Insect Diagnostic Lab
Barriers & Row Cover§ Fine mesh screening can physically block access to plants
Photo Credit: Aaron Baugher, via flickr
§ Considerations: § Plant size§ Pollinator access§ Aesthetics
39
2/7/20
7
University of Wisconsin: Insect Diagnostic Lab
Traps§ Contain:
§ Synthetic version of JB sex pheromone § Plant volatiles
§ Traps can collect a lot of Japanese beetles!
§ Limited applicability for control
§ Tend to result in increased damage
!
40
University of Wisconsin: Insect Diagnostic Lab
Biological Control§ Use of natural enemies to reduce pest levels
§ Many natural enemies feed on or attack Japanese beetles:§ Predators§ Parasites§ Pathogens
i.e., Relying on Mother Nature to help out!
41
University of Wisconsin: Insect Diagnostic Lab
Biological Control: Predators
Photo Credit: Michael Coghlan via flickr
Ants
Photo Credit: David Cappaert, Bugwood.org
Predatory Ground Beetle
Photo Credit: Tom Friedel via Wikipedia
Insectivorous Mammals
Photo Credit: Alexey Komarov via Wikipedia
Wild and Domestic Birds
42
University of Wisconsin: Insect Diagnostic Lab
Vertebrates: A Double-Edged Sword?
From: USDA Technical Bulletin 1383
Crow digging for grubs
Photo Credit: Marie-Lan Nguyen via Wikipedia
43
University of Wisconsin: Insect Diagnostic Lab
Biological Control: ParasitesTiphia sp. Wasp Attacking White Grub
Photo Credit: M. Rogers and D. Potter, University of Kentucky
Entomopathogenic Nematodes
Photo Credit: Peggy Greb, Bugwood.org
Winsome Fly
Photo Credit: Whitney Cranshaw, Bugwood.org
44
University of Wisconsin: Insect Diagnostic Lab
Biological Control: Pathogens
Photo Credit: David Cappaert, Bugwood.org
Milky Spore Disease (Paenibacillus popilliae)
[Bacterial]Green Muscaridine Disease
(Metarhizium anisopliae)[Fungus]
!Photo Credit: Svetlana Y. Gouli, Bugwood.org
45
2/7/20
8
University of Wisconsin: Insect Diagnostic Lab
Chemical Controls:
§ Each approach uses different products and/or tactics
§ Targeting one life stage has minimal impacts on the others
§ Focus on what plant(s) you’re trying to protect!
Disclaimer: The mention of products and active ingredients is not an endorsement
46
University of Wisconsin: Insect Diagnostic Lab
Grub Control in Turfgrass§ To protect lawn…not prevent future damage by adult beetles
§ Preventative:§ “Proactive”§ Prevents grub damage from occurring—but is it needed?
§ Curative:§ “Reactionary”§ In response to presence of grubs
Regardless of approach and products used, grub control products mustbe watered in to reach the root zone where grubs are feeding
47
University of Wisconsin: Insect Diagnostic Lab
§ Applied before or around the time of egg hatch§ Most effective against very small grubs (90+% control)
§ NOT effective against large grubs§ Products have long-residual activity (> 100 days)
§ Product Ingredients:§ Chlorantraniliprole§ Cyantraniliprole
§ Imidacloprid § Dinotefuran§ Clothianidin* § Thiamethoxam*
Preventative Grub Control
Neonicotinoid Class:These products are highly toxic to bees, if exposed
48
University of Wisconsin: Insect Diagnostic Lab
Conserving Pollinators in Turfgrass Areas§ Several tactics can greatly
minimize risks to pollinators when grub controls are used:
§ Weed control§ Mow before applying grub
control§ Use granular products§ Choose non-neonicotinoid
products
Extension Publication A4128
49
University of Wisconsin: Insect Diagnostic Lab
§ Applied once grubs are observed at threatening levels§ Most effective against smaller grubs
§ Not as effective as preventative controls§ Products have short residual activity (<10 days)
§ Product Ingredients:§ Carbaryl (Sevin†)§ Trichlordon (Dylox)
§ Bacillus thuringiensis galleriae§ Entomopathogenic nematodes§ Milky spore§ Metarhizium
Curative Grub Control
Broadcast Spreader
Photo Credit: Wikipedia
Conventional
Organic
50
University of Wisconsin: Insect Diagnostic Lab
Timing of Grub Control
Photo Credit: University of Nebraska Lincoln
Preventative Curative
51
2/7/20
9
University of Wisconsin: Insect Diagnostic Lab
Small Plants (Shrubs, Flowers, Gardens)§ Foliar applications of contact insecticides typically used§ Applications to blooming flowers pose risks to pollinators§ Short residual activity
§ Carbaryl§ Bifenthrin§ Cyfluthrin§ Cyhalothrin§ Cypermethrin§ Deltamethrin§ Permethrin§ Chlorantraniliprole
ConventionalOrganic
§ Insecticidal soap§ Horticultural oils (neem, etc.)
§ Azadirachtin§ Pyrethrins§ Bacillus thuringiensis galleriae
52
University of Wisconsin: Insect Diagnostic Lab
Large Plants (Trees)§ Systemic products can be applied preventatively
§ Typically applied as a soil drench§ Ex. Imidacloprid, Thiamethoxam
§ Can take several weeks for uptake in large trees
§ Can pose risks to bees§ Wait until after plants have bloomed to apply§ Use restricted on lindens due to pollinator concerns
Do not apply this product, by any application method to linden, basswood, or other Tilia species
53
University of Wisconsin: Insect Diagnostic Lab
Questions?
Notes available at:
insectlab.russell.wisc.edu
54