An Evaluation of Factors Limiting Plant Establishment at Malheur Lake
February 2021 - May 2023
- High Desert Partnership
During most of the 1900s, Malheur Lake at Malheur National Wildlife Refuge supported an abundant mixture of emergent and submergent vegetation. However, after deep and prolonged flooding in the 1980s, vegetation disappeared and has not reestablished throughout most of the lake. In this study, we are using seedbank experiments and exclosures to identify the factors affecting germination and establishment. The seedbank experiment will determine whether an adequate seedbank exists in the soils. The exclosures, placed across an elevation gradient, weill determine whether herbivory is affecting establishment. During the first year of the study, numerous germinants were observed in the seedbank experiment and extensive germination occurred in the exclosures. However, following germination in the exclosures, the majority of plants died presumably due to soil moisture declines. The second year of the study will include a seedbank analysis from a larger portion of the lake, continued evaluation of the exclosures, and more extensive soil moisture monitoring.