Objective 2a.
Develop a qualitative and quantitative understanding of invasive plant growth, development, reproductive biology and competitive relations that make Yellow starthistle, saltcedar and giant reed, highly invasive and destructive to US agriculture and the environment.
California/ Nevada
Arundo- Plant growth analysis in relation to soil and water nutrients and other environmental growth factors such as temperature will be studied; T. Dudley & D. Spencer
Yellow starthistle- Development of a degree-day model to predict Yellow starthistle plant growth, development and reproduction with emphasis placed on nutrients, plant growth structure, root dynamics and resulting plant quality will be completed; J. DiTomaso, M. Pitcairn, D. Spencer and R. Carruthers
Tamarix- determining plant growth characteristics of Tamarix spp. under California conditions, especially in competition with other species such as willows and Arundo donax (see Objective 2c); T. Dudley
Colorado/ Wyoming
Tamarix- Field plant growth data will be collected and supplied to others conducting modeling studies on saltcedar growth and development; D. Eberts & D. Kazmer
Texas/ New Mexico
Tamarix- Development of a plant growth model for saltcedar will be conducted and will contribute to modeling competition studies of saltcedar and other species ; J. Kiniry
Objective 2b.
Investigate the biology and ecology of insect and plant pathogenic natural enemies of the invasive pest plants, develop and assess their target and non-target impacts, and develop methods to use them in integrated weed management programs.
California/ Nevada
Yellow starthistle- Existing natural enemies of Yellow starthistle will be assessed for their basic biology and development, including life-table studies of some species; R. Carruthers, M. Pitcairn and N. Carruthers
Yellow starthistle- Insect natural enemy simulation models will be developed to estimate recruitment, survivorship, reproduction and population dynamics of existing natural enemies of Yellow starthistle; M. Pitcairn, N. Carruthers & R. Carruthers
Diorhabda- Diapause control and population level assessments of its impact on the establishment and effectiveness the leafbeetle will be assessed; D. Bean, R. Carruthers & T. Dudley
Diorhabda- Pheromone characterization and development of new monitoring methods; D. Bean & T. Dudley
Diorhabda- Laboratory and field assessments of non-target affects on Frankenia spp. in California will be conducted both pre- and post-release; R. Carruthers, T. Dudley & J. Herr
Diorhabda- Laboratory and field phenology and survival assessments under California and Nevada environments including life-table studies will be investigated; N. Carruthers, R. Carruthers, J. Knight and T. Dudley
Leafhoppers- Assessment of the impacts of Opsius leafhoppers on Tamarix and their interactions with new biological control agents will be conducted; T. Dudley
New agents- Host range testing and basic biology of new saltcedar agents will be assessed under quarantine conditions; R. Carruthers & J. Herr
Colorado/ Wyoming
Diorhabda- Field phenology and survival assessments under Colorado and Wyoming environments including feeding behavior, oviposition, and dispersal and studies; D. Eberts & D. Kazmer
Non-target impacts- Field populations of Frankenia jamesii will be assessed at the Pueblo, Colorado site for potential impact by the newly released Diorhabda elongata; D. Eberts
Texas/ New Mexico
Diorhabda- Development of a pheromone-base trapping and assessment sYellow starthistleem; P. Lewis and J. DeLoach
Diorhabda- Laboratory assessment of non-target affects on Frankenia spp. in Texas; J. DeLoach and P. Lewis
Diorhabda- Field and lab studies to quantify the impact of leafbeetle defoliation on saltcedar growth and survival; A. Knutson
New agents- Host range testing and basic biology of new saltcedar agents will be assessed under quarantine conditions; D. Thompson
Objective 2c.
Characterize and evaluate synergistic and antagonistic interactions for various natural enemies, the target pest plant species and abiotic and biotic elements that affect the community level dynamics of riparian ecosYellow starthistleems.
California/ Nevada
Yellow starthistle- Spatial and temporial synchrony with the host plant, attack levels, and impact on Yellow starthistle growth will be assessed for specific natural enemies; N. Carruthers, R. Carruthers, M. Pitcairn and D. Spencer
Yellow starthistle- The effects of soil nitrogen levels on natural enemy growth and survival will be assessed as it is mediated by plant tissues nitrogen levels; M. Pitcairn & D. Spencer
Arthropon predation- Evaluation of the effects of insect and spider predation on the establishment and population increase of Diorhabda elongata will be studied; R. Carruthers, T. Dudley & A. Herrera
Non-arthropon predation- Evaluation of the effects of bird and small mammal predation on the establishment and population increase of Diorhabda will be assessed in California and Nevada study sites; B. Longland & D. Kazmer
Tamarix- Defoliation studies will be conducted to estimate feeding rates of Diorhabda elongata and its impact on seedling saltcedar plants; R. Carruthers, J. Gould & J. Herr
Tamarix- Spatial and temporial synchrony with Tamarix, attack levels, and impact will be assessed for Diorhabda elongata; R. Carruthers, T. Dudley and D. Bean
Tamarix- Studies on the accumulation of liter and its breakdown will be related to nutrient cycling, plant growth and species diversity; T. Dudley
Tamarix- Multi-agent feeding studies will be conducted looking at the interactions of leafhoppers and leafbeetles on Tamarix growth and development; T. Dudley
Wildlife- The effects of saltcedar invasion and control will be assessed on biological diversity in riparian habitats in California and Neveda; B. Longland & T. Dudley
Wildlife- Species diversity will be compared between native cottonwood/ willow stands and saltcedar infested areas, concentrating on insect, small mammal and bird populations; D. Dahlston, T. Dudley, A. Herrera & J. Knight
Colorado/ Wyoming
Arthropon predation- Evaluation of the effects of insect and spider predation on the establishment and population increase of Diorhabda elongata; D. Kazmer and D. Eberts
Non-arthropon predation- Evaluation of the effects of bat, bird and small mammal predation on the establishment and population increase of Diorhabda elongata Opsius stactogalus; D. Eberts & D. Kazmer
Site adaptation- Field studies on species adaptation, establishment and competitiveness in vegetative restoration; S. Wynn and K. Lair
Texas/ New Mexico
General- Faunistic survey of insects on saltcedar and native shrubs in the Northern Plains including tree fogging studies; D. Eberts & D. Kazmer
Tamarix competition- Field studies will be conducted on saltcedar competition with native vegetation under growing conditions in the southwest; D. Thompson
General- Faunistic survey of insects on saltcedar and native shrubs will be completed in portions of the Southern Plains; A. Knutson
Objective 2d.
Conduct landscape level assessments and predictions of invasive species distribution, assess competition with beneficial species and determine the effects of these pest plant dominated habitats on local and watershed level diversity of associated flora and fauna.
California/ Nevada
Plant/soil relations- The effects of saltcedar infestations on soil quality will be assessed over landscape levels of concern to estimate habitat degradation; T. Dudley
Aerial survey- Remote sensed aerial imagery will be tested for its use in assessing Tamarix, Yellow starthistle and Arundo donax density and natural enemy impact on these target plants using Geographical Information Yellow starthistle ems and spatial models; G. Anderson , R. Carruthers & A. Hurerra
Colorado/ Wyoming
Aerial survey- Remote sensed aerial imagery will be tested for its use in assessing Tamarix density and natural enemy impact using Geographical Information SYellow starthistleem models; G. Anderson & D. Kazmer
Texas/ New Mexico
Aerial survey- Remote sensed aerial imagery will be tested for its use in assessing Tamarix density and natural enemy impact using Geographical Information SYellow starthistleem models; J. Evertt
Objective 2e.
Develop re-vegetation strategies, integrate control methods, and test decision models for use in implementing control and re-vegetation under varying environmental conditions.
California/ Nevada
Tamarix- Seedbank assessments will be conducted throughout various habitats to determine the extent of seed viability under differing conditions; T. Dudley
Tamarix- Natural revegetation of native species will be studied under simulated herbivory to mimic biological control impacts; T. Dudley
Tamarix- Revegetation of native species will be evaluated in various California habitats in competition with saltcedar and Arundo donax; T. Dudley
Colorado/ Wyoming
Tamarix- Natural revegetation of native species will be studied under simulated herbivory to mimic biological control impacts; D. Kazmer and S. Wynn
Sequential seeding- The use of sequential seeding methods for establishment of forbs, shrubs and trees will be determined in saltcedar impacted restoration sites; S. Wynn and K. Lair
Tamarix- Soil nitrogen availability and the impacts of mycorrhizal inoculation on plant dynamics in saltcedar restoration sites will be assessed; S. Wynn and K. Lair
Texas/ New Mexico
