Treesearch

Invasive clonal species may exhibit different growth strategies than their native clonal competitors. In this study, we examined the spatial distribution of tiller outgrowth and the bud bank by comparing the investment in phalanx versus guerilla growth of a native and invasive perennial grass in North America. We also examined the effect of altered precipitation frequency, clipping, and competition on their clonal growth strategies. Investment in phalanx and guerilla growth was assessed by examining live propagule and tiller production from the plant crown versus its rhizomes. Although...

Background: Contemporary and projected shifts in global fire regimes highlight the importance of understanding how fire affects ecosystem function and biodiversity across taxa and geographies. Pyrodiversity, or heterogeneity in fire history, is often an important driver of biodiversity, though it has been largely overlooked until relatively recently. In this paper, we synthesise previous research to develop a theoretical framework on pyrodiversity–biodiversity relationships and propose future research and conservation management directions.Theoretical Framework: Pyrodiversity may affect...

1. Ecological restoration is beneficial to ecological communities in this era of largescale landscape change and ecological disruption. However, restoration outcomes are notoriously variable, which makes fine-scale decision-making challenging. This is true for restoration efforts that follow large fires, which are increasingly common as the climate changes.2. Post-fire restoration efforts, like tree planting and seeding have shown mixed success, though the causes of the variation in restoration outcomes remain unclear. Abiotic factors such as elevation and fire severity, as well as biotic...

Aim: Managers are increasingly facing an uncertain future given changing climates and ecological trajectories. The interacting effects of climate, natural disturbance, and management actions complicate future projections, and there is a need for approaches that integrate these factors - especially for predicting future vegetation and species richness. Location: Central Sierra Nevada Mountains, USA.Methods: We used outputs from a spatially explicit landscape disturbance succession model that incorporated forest management actions, disturbance, and climate to estimate habitat and potential...

The La Sal Mountains are an isolated sky island in southeast Utah. These high-altitude ecosystems are especially vulnerable to climate change and human-caused disturbances. In 2013 and 2014, the Utah Division of Wildlife Resources (UDWR) introduced nonnative mountain goats to the La Sals to enhance hunting and wildlife viewing opportunities. Recreation has increased in the area since then. Mountain goats and increased recreation are affecting plant species of conservation concern, suggesting that an adaptive management approach may be needed to maintain the ecosystem and the sensitive...

Inter-rotational productivity (i.e., productivity of successive rotations) of ponderosa pine plantation was measured on experimentally treated plots with a common design at three diverse sites in northern California. The objectives were to examine the carryover effect of fertilization (F) and understory control by herbicide (H), applied in the first rotation of plantation, on growth in the second rotation and to determine the sustainability of plantation productivity between rotations. Carryover effect varied among the three sites. There was a significant and positive H and F effect (P <...

Forage quality and quantity are nutritional attributes that influence ungulate populations through bottom-up processes. In northern Idaho, harsh winters occasionally cause substantial mortality of elk (Cervus canadensis) and deer (Odocoileus hemionus) populations; however, recent studies in the Western United States show that nutritional deficiencies on summer range also affect populations by reducing reproduction and survival. In fact, in many settings, nutritional deficiencies in summer may have a more limiting effect on elk populations than deficiencies in winter. Large tracts of mid-...

Restoring current ponderosa pine (Pinus ponderosa Dougl. Ex P. and C. Laws)-dominated forests (also known as “dry forests”) to spatially resilient stand structures requires an adequate understanding of the overstory spatial variation of forests least impacted by Euro-American settlers (also known as “reference conditions”) and how much contemporary forests (2016) deviate from reference conditions. Because of increased tree density, dry forests are more spatially homogeneous in contemporary conditions compared to reference conditions, forests minimally impacted by Euro-American settlers....

Information on spatial patterns of forest health and stand vigor in historical forests is quite limited, particularly for forests of North America, which have been subsequently harvested. We used forest inventory data from 1934, which pre-dated early 20th century timber harvest, to reconstruct patterns of vigor in overstory trees. Across 4,000 ha of ponderosa pine-dominated forests in the Blacks Mountain Experimental Forest (BMEF), we described the spatial patterns of pre-harvest (1934) forests using a stand density index (SDI) and accounting for different species and vigor classes. We...