Biological Control of

Saltcedar

White River Municipal Water District

Saltcedar

Tamarix spp.

• Introduced to the United

States from Asia in the 1830s

• Invasion of 17 western

states and Texas river

systems

•Growth characteristics –

Water usage and salt

depositing

Saltcedar – Methods of Control

Chemical Treatment

Imazapyr

Imazapyr + Glyphosate

Triclopyr (Low-Volume

Basal Treatment)

Saltcedar – Methods of Control

Mechanical Treatment

Excavator, Bulldozer, Skid-

Loader, etc…

Cost prohibitive

Ground disturbance

Saltcedar – Methods of Control

Biological Treatment

Saltcedar leaf beetle –

Diorhabda elongata

Other natural enemies –

Leafhopper, scale

insects

Establishment of the Saltcedar leaf

beetle in Texas watersheds

First established at Big Spring in 2004

23 release sites in west Texas

TAES attempted releases in 2007 and 2008 at WRMWD

WRMWD repeated stocking effort in 2009

The initial release at White River was the Uzbek species of beetle; the second and third releases were the Crete species.

Coniatus – Mediterranean weevil that has been found throughout much of Texas

Saltcedar Leaf Beetle Life Cycle

Egg

Larva

Pupa

Adult

Defoliation of Saltcedar

Carbohydrates

storage in root

crown

Repeated

defoliation effects

Results of

defoliation

White River Municipal Water District

Saltcedar Infestation White River MWD

Chemically Treated Area – 2007 White River MWD

Initial Establishment Point White River MWD

Saltcedar Control Area – Fall 2009 White River MWD

Saltcedar Control Area – Fall 2010 White River MWD

Saltcedar Control Area – Fall 2011 White River MWD

Saltcedar Control Area – Fall 2012 White River MWD

WRMWD Beetle Population Growth

2007 2008 2009 2010 2011 2012

0

200

400

600

800

1000

1200

Area of Defoliation (ac)

Area of Defoliation (ac)

Saltcedar Biological Control - FAQ

Does the saltcedar leaf beetle feed on any other species of tree?

What are the limiting factors (predation, weather, etc…) during beetle

establishment?

Will the leaf beetles ever eradicate the saltcedar on WRMWD?

What happens when there is no saltcedar for the beetles to eat?

Sources:

Texas Agrilife Extension Service (TAES)

Texas A&M University

USDA – ARS

USDA – NRCS