An ArcGIS Online (AGOL) page containing historical and predictive maps developed by James Hatten of the USGS for the southwestern willow flycatcher habitat across the southwestern United States. The model outputs a range of probabilities for suitable and less suitable habitat in 20% probability classes. This project shows that the satellite model adequately predicts flycatcher habitat rangewide, but it lacks the ability to predict which patches will be occupied in a given year.
A two-part study looking at how changes in soil salinity affect tamarisk growth and how beetle-induced defoliation affects tamarisk growing in soils with different salinities. Results showed that tamarisk plants grow better in soils with a similar salinity to their own origin site and that lower salinity does not benefit tamarisk plants adapted to higher saline conditions.
What site conditions are associated with greater recovery and overall higher cover of willows? Goetz et al. performed a meta-analysis of tamarisk removal and willow (Salix) recovery across the southwest, compiling data from 260 sites where tamarisk was subject to active removal and/or biocontrol and 132 reference sures. Cut-stump method with biological control was the most effective method to improve native species dominance. Willow cover was generally highest in locations with low drought stress, as reflected by soil properties, distance to water, and climate.
A study subjecting tamarisk from two distinct populations originating from areas with greatly varying soil salinities to a range of different salinities. Results showed dramatic differences between growth with the low salinity population accumulating 72% more biomass when grown at 4 ppt compared to 16 ppt, while the high salinity population produced 50% more biomass when grown at 16 ppt. Additionally, the high salinity population had a lower turgor loss point and exhibited greater stomatal control relative to the low salinity population.
Nagler et al. test the assumption that removing saltcedar (Tamarix spp.) will save water and create environments more favourable to these native species. They compared sap flux measurements of water used by native species in contrast to saltcedar, and compared soil salinity, ground water depth and soil moisture across a gradient of 200–1500 m from the river's edge on a floodplain terrace at Cibola National Wildlife Refuge (CNWR).
Glenn et al. measure transpiration and stomatal conductance to investigate the environmental constraints on an arid-zone riparian phreatophtye, saltcedar (Tamarix ramosissima and related species and hybrids), growing over a brackish aquifer along the Colorado River in the western U.S. Depth to groundwater, meteorological factors, salinity and soil hydraulic properties were compared at stress and non-stressed sites that differed in salinity of the aquifer, soil properties and water use characteristics, to identify the factors depressing water use at the stress site.
Bush et al. use a common garden experiment to study drought sensitivity in non-native tamarisk. They found some populations are more sensitive to soil water deficits than others and that freeze-thaw exposure reduces drought sensitivity.
Bush, S.E., Guo, J.S., Dehn, D., Grady, K.C., Hull, J.B., Johnson, E., Koepke, D.F., Long, R.W., Potts, D.L. and Hultine, K.R., 2021. Adaptive versus non-adaptive responses to drought in a non-native riparian tree/shrub, Tamarix spp. Agricultural and Forest Meteorology, 301, p.108342.