Recent ucsc_eeb_researchpubs items

Clave para la identificación de las plántulas del valle de Coto Brus

Fri, 27 Mar 2026 00:00:00 +0000

Clave para la identificación de las plántulas del valle de Coto Brus

Fungal Fighters - A Fungal Competition Lab Module for Budding Microbiologists: Supplemental Teaching Materials

Wed, 11 Dec 2024 00:00:00 +0000

Plants make up 80 percent of our food, but up to 40 percent of global food crops are lost to plant pests and diseases each year (FAO, 2019). Scientists try to mitigate disease impacts by identifying microscopic pathogens such as fungi and running experiments to study their traits and how they affect plants. In this module, students build on previous knowledge of ecosystem interactions and energy flow by learning about pathogenic fungi that consume plants. Students may be familiar with edible mushrooms and the role of fungi in decomposition, but this module highlights another ecosystem function of fungi — agents of plant disease. This module synthesizes broad concepts in biology and ecology with an emphasis on agricultural implications. Students collect diseased leaf samples from around their neighborhood, culture their own fungal species, and explore the diversity of fungi that infect local plants. Students learn sterile technique, microscopy, and other lab skills central to microbiology,...

A Germination Study: Dormancy in ray achenes of Holocarpha macradenia, a rare coastal prairie forb

Tue, 22 Aug 2023 00:00:00 +0000

A Germination Study: Dormancy in ray achenes of Holocarpha macradenia, a rare coastal prairie forb

Halophyte Response to Drought and Salinity Stress and Implications for Restoration

Mon, 8 Aug 2022 00:00:00 +0000

Due to global loss and degradation of salt marshes, restoration and conservation havebecome necessary to protect and preserve salt marsh systems. Restoration can exacerbate the common environmental stressors – salinity and drought – present in Mediterranean salt marsh ecosystems. Grading and clearing of land to restore tidal influence and remove non-native weeds creates large expanses of bare soil, increasing evaporation rates. As moisture is lost, salts are concentrated in the soil, making growing conditions more difficult for transplants. Multiple species are usually planted during revegetation efforts, but different species are likely to vary in tolerance to moisture and salinity stress; yet, the relative effect of these stressors on manyCalifornia salt marsh natives are unknown. To address this knowledge gap, we appliedgreenhouse watering treatments to five perennials common in central California coast salt marshes. We evaluated response to water volume and salinity by measuring...

Allelopathic alkaloids of an invasive shrub and their effect on the growth of ectomycorrhizal fungi

Mon, 8 Aug 2022 00:00:00 +0000

One mechanism of invasive species success is the production of allelopathic chemicals that negatively affect native competitors. A highly invasive shrub, Cytisus scoparius, impedes Douglas-fir tree establishment in clearcuts, even years after its removal. This impediment may be from the allelopathic alkaloids of C. scoparius that could indirectly hinder Douglas-fir by inhibiting their mutualistic ectomycorrhizal fungi (EMF). I extracted and quantified alkaloids from C. scoparius tissue for use in a laboratory bioassay. I then tested if and how these alkaloids affected EMF growth. In a second assay, I tested the effects of three concentrations of pure sparteine, the primary alkaloid in C. scoparius , on fungal growth. Sparteine was the only alkaloid recovered from the extraction which yielded 0.32 mg sparteine/g fresh weight, a lower concentration than previously reported values. Both the crude extract and pure sparteine significantly affected...

Chemical and Mechanical Control of Cytisus scoparius Across the Life Cycle. Technical report submitted to Joint Base Lewis-McChord.

Sun, 18 Aug 2019 00:00:00 +0000

At Joint Base Lewis-McChord, tree plantations have failed repeatedly in areas that had once supported Douglas fir forest, with Scotch broom invasion replacing forest. Maximizing the effectiveness of Scotch broom control is a top management priority. The studies presented here have two main foci: timing of control relative to the Scotch broom life cycle, and chemical vs. manual control. We also explore the effects of forest edges on Douglas fir seedling survival and mycorrhizal colonization.

We set up a large-scale experiment (6.3ha total treatment area) at 5 heavily invaded sites in which all broom was mechanically removed in 2007. Each site contained 4 blocks of 12 treatments. We measured density of newly germinated seedlings using 24m-long, 10cm-wide belt transects, and percent cover of Scotch broom using line-intercept method on 24m transects.

Seedling density (representing germination from the seedbank) peaked in year 2 and varied dramatically among sites,...

Forest Regeneration under Scotch Broom Control. Technical report submitted to Fort Lewis and The Nature Conservancy.

Sat, 17 Aug 2019 00:00:00 +0000

The pest plant Scotch broom (Cytisus scoparius) is hindering effective reforestation at Fort Lewis, resulting in both a loss of land available for military training as well as a loss of native forest habitat for native plants and animals. Our primary objective was to examine the relative effectiveness of different broom control strategies that are appropriate for the forestry context, where the use of fire is not permitted. This document reports on the first year’s activities of a large research collaboration between personnel at the University of California Santa Cruz and at Fort Lewis. Key research questions include: What are the costs and benefits of an extended preliminary treatment phase, including two or even three years of soil scarification and control of small broom plants before planting? What is the relative effectiveness of chemical and mechanical treatment?

We set up a large-scale experiment (6.3ha total treatment area) at 5 sites, with a blocked...

Forest Regeneration under Scotch Broom Control, Phase I Progress. Technical Report submitted to Joint Base Lewis-McChord and The Nature Conservancy.

Sat, 17 Aug 2019 00:00:00 +0000

Sustainable forestry has been practiced for over a hundred years on the 16,000 ha of commercial forest lands on Joint Base Lewis-McChord. In the latter half of the 20^thcentury, the invasive shrub Scotch broom spread across the base, creating new challenges for reforestation efforts. Large areas of forest were essentially taken over by Scotch broom after trees were harvested. Plantations have shown repeated failures, resulting in serious financial losses as well as a negative effect on military training. The primary objective of our project was to examine the impact of Scotch broom on establishment and growth of Douglas fir seedlings, and the effectiveness of different approaches to Scotch broom control in the forestry context. Here we report results from a number of related studies on [1] Douglas fir survival in previously invaded clearcuts, [2] Edge effects on Douglas fir survival, [3] Stimulating germination with disturbance, [4] Increase in...