Biocontrol of Rangeland Weeds - Western Colorado Insectswci.colostate.edu/Assets/pdf/PMW2013/Bean.107.pdf · (numbers are for 2010 except for J. ivannikovi which is 2012 ... Dalmatian

Pest Management Workshop 2013

Bean, Rangeland Pest Control

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Biocontrol of Rangeland WeedsTRA Pest Management Workshop, Feb 20, 11:15 am

Dan Bean

Colorado Department of Agriculture

Palisade Insectary

[email protected]

Palisade Insectary

� Began in the 1940’s to fight Oriental fruit

moth, a project that helped peach farmers

and is still going

� Moved to new 14,000 sq. ft. facility in 1992

� Distributes over 20 biocontrol agents for the

control of insect pests and weeds

� Is a partner in pest management

Who are we?

Outline

• What is biological control?

• Is biological control safe?

• Is biological control effective?

• What weeds can we control using biological

agents?

• Russian knapweed, yellow toadflax and

Canada thistle; new agents for rangeland

weeds.

What is biological control?

Biological control (biocontrol) is the use of

natural enemies, including insects, mites and

pathogens, to control pests, including insect

pests and noxious weeds.

Calophasia lunula on Dalmatian toadflax Macrocentrus ancylivorus stings host

Classical Weed Biological ControlThe reunification of host specific natural enemies with invasive plants

2001

Diorhabda carinulata

Tamarix spp

Tamarisk

1830

Leaf beetle

Biological Control

The use of natural enemies to control pest organisms

Field bindweed gall mites Macrocentrus parasitic wasp

Flea beetle on leafy spurge

tamarisk leaf beetle collection

�Safe

�Effective

�Inexpensive

�Sustainable



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Biological Control

The use of natural enemies to control pest organisms

balance

Chemical, BiologicalCultural, Mechanical

Integrated Pest Management

Field bindweed gall mitesMacrocentrus parasitic wasp Flea beetle on leafy spurge

tamarisk leaf beetle collection

Natural enemy added…

The results of weed biocontrol are a new

equilibrium between the introduced plant

and natural enemies of the plant

…long term ecological solution

Weed Suppression

Never Eradication!

Natural enemy added…

The results of weed biocontrol are a new

equilibrium between the introduced plant

and natural enemies of the plant

…long term ecological solution

1. Opens canopy (increases site availability)

2. Decreases seed production (decreases

species availability)

3. Slows growth or may kill (decreases species

performance)

Ecologically Based Invasive Plant Management

1. Site Availability2. Species Availability3. Species Performance

(successional weed management)

www.ebipm.org



www.ebipm.org

Biological Control

May open up new sites for desired plants

Decreases seed production of target weeds

Decreases competitive ability of target weeds


Restoration Islands


tamarisk biocontrol



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Defoliated tamarisk in the midst of other tree species that remain untouched

Moab, Utah

Yes, only host specific insects are used and no record of host switches during

the 65 years of weed biocontrol in NA

Is biological control safe? Generalists vs. Specialists:Only Specialists are used!

Most plant feeding insects are adapted to a single plant

species or a small group of closely related plant species.

Some groups, like many grasshopper species, are generalists

and feed on a wide range of plants

Host Plant

Leafy spurge

Diffuse and spotted knapweed

Russian knapweed

tamarisk

Various crops

Insect

Leafy spurge flea beetles

Knapweed root weevil

Russian knapweed gall fly

Tamarisk beetle

Grasshoppers (various species)

Steps in weed biological control

Identification of target/background research

Overseas exploration and research to find agent or

agents

Quarantine work including agent cleanup and host

range testing

Approval from regulatory agencies (TAG, APHIS)

Field testing including monitoring

Full scale implementation

10-20 years!

Before After

Before and after release of leafy spurge flea beetles and long horned

beetles, complete control (not eradication) of leafy spurge in pasture

land near Pine, Colorado

Flea beetlesOberea adult

Is biological control effective?

leafy spurge

What weeds can we control using

biological agents?

spotted knapweed Russian knapweed

Providing biocontrol agents/ developing biocontrol programs

(numbers are for 2010 except for J. ivannikovi which is 2012)

Leafy Spurge Aphthona spp 200,000

Oberea erythrocephala 1000

Field Bindweed Aceria malherbae 900,000 (est)

Tyta luctuosa 27,410

Dalmatian toadflax Mecinus janthiniformis 11,115

Calophasia lunula 6806

Yellow toadflax Rhinusa linariae 300

Mecinus janthinus 800

Knapweeds Larinus minutus 4600

Russian knapweed Jaapiella ivannikovi 1,788 galls

Musk thistle Trichosirocalus horridus 3400

Canada thistle Urophora cardui 5020

Puncturevine Microlarinus spp 4300

Tamarisk Diorhabda carinulata 300,000



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field bindweed Bindweed mites are microscopic and cause the leaves to curl into galls

Diffuse and spotted knapweed biological control Cyphocleonus achates

prefers spotted, will hit diffuse

larvae feed on roots

eggs

pupae

adults feed on foliage

Larvae

Larinus minutus

Knapweeds (diffuse and spotted)

Tamarisk biological control




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Larva

egg mass


Adult

Tamarisk Mortality in Western Colorado

2009-2011

0

10

20

30

40

50

60

Flume Knowles Saltcreek 2 Bedrock SY Burned SY Unburned

Site

Pe

rce

nt

Mo

rta

lity

2009

2010

2011

Tamarisk mortality at six field sites in western Colorado measured over three seasons. Sites were defoliated by beetles for the first time in either 2007 or 2008 and all sites had been defoliated at least four times by 2011. Of the ten sites in this study four have had no mortality and are not shown.

Mortality

Yellow toadflax biological control Mecinus janthinus a stem boring

weevil on yellow toadflax

• this species was collected on both yellow and

Dalmatian toadflax in Europe. The Dalmatian

toadflax weevil was later found to be a separate

species, now named Mecinus janthiniformis.

• numerous releases on yellow toadflax in

Colorado were probably the Dalmatian toadflax

weevil, which would explain why they never did

well on yellow toadflax.

• The CDA has a program to establish and

release the yellow toadflax weevil. Since 2009

we have received and released over 1,000 adult

weevils, through the USFS, from established

populations in Montana. So far we have three

sites where they are established.

Russian knapweed biological control

Jaapiella ivannikovi is looking like a promising agent. This fly lays eggs in shoot tips and stops growth and flowering.

The flies were obtained from Rich Hansen, USDA APHIS in Ft. Collins.

adult fly

gall



6

2 mm

A gall may contain up to 30 larvae of the gall fly. They are small but very effective in stopping shoot growth. Adults emerge about 2 weeks after gall formation. Adults are about the

size of a fruit fly.

Larvae pupate within galls

1,800 Russian knapweed galls were released this year. This number was divided into 63 open field releases. Five releases were made in the Arkansas Basin; more releases are needed next season considering the massive infestations in the basin.

1. We harvested about 1,700 galls from the Insectary garden in 2012

2. We did more than 63 open field releases in 2012

3. We monitored 12 field sites in 2012

4. We plan to add at least 8 more monitoring sites and release at least 2,000 galls in 2013

The Russian knapweed gall fly program

Canada thistle biological controlPuccinia punctiformis Puccinia punctiformis (F. Strauss) Rohl.(F. Strauss) Rohl.

••First plant pathogen First plant pathogen

suggested as biological suggested as biological

weed control agent (weed control agent (1893)1893)

••Occurs throughout range Occurs throughout range

of of C. C. arvensearvense

••Naturalized in N. AmericaNaturalized in N. America

••Obligate rust pathogenObligate rust pathogen

••AutoeciousAutoecious

••BrachyBrachy--form (aeciospores form (aeciospores

morphologically morphologically

indistinguishable from indistinguishable from

urediniospores)urediniospores)

••HeterothallicHeterothallic

••Restricted hostRestricted host--range range

(only (only C. C. arvensearvense as host in as host in

nature)nature)

••Causes systemic disease Causes systemic disease

that ultimately kills that ultimately kills C. C.

arvense arvense patchespatches Systemically diseased shoot with haploid spermagonia Systemically diseased shoot with haploid spermagonia

(yellow pustules) and dikaryotic aecia (brown pustules) (yellow pustules) and dikaryotic aecia (brown pustules)

resulting from fertilization of spermagoniaresulting from fertilization of spermagonia



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Dr. Dana Berner, USDA ARS

Monitoring sites needed for release and evaluation of

biological controls by the CDA

1. Russian knapweed infestations, 2 acres or more, need to set up long term

monitoring and release of gall flies and possibly other agents as they

became available

2. Canada thistle infestations, half an acre or more where no spraying is

planned. We will set up monitoring site and release Canada thistle rust,

which is host specific and already found in the US.

Russian knapweed monitoring

Please contact Dan Bean at (970) 464-7916 or

write to [email protected]

Thanks to:

Everyone at the Palisade Insectary

Cooperators, including land owners willing to let us monitor our work

Dr. Dana Berner of the USDA ARS for the Canada thistle rust slide

Bob Hammon, CSU Extension for arranging the program

Documents

Biocontrol of Rangeland Weeds - Western Colorado Insectswci.colostate.edu/Assets/pdf/PMW2013/Bean.107.pdf · (numbers are for 2010 except for J. ivannikovi which is 2012 ... Dalmatian