Santa Cruz Island Reserve

13 Feb, 04 PM - 15 Feb, 04 PM

Most of what we know about the way plants and animals interact stems from studies of the interactions between aboveground plant parts and aboveground herbivores. Belowground herbivory has especially strong direct effects because of the importance of roots to plants. Without accounting for the impacts of root herbivores theories regarding plant-herbivore interactions may be incomplete. Furthermore, a lot of work has been done on plant responses to root herbivory in short term studies, but no work has been published on plant responses to root herbivory on an evolutionary time scale. I will compare the Channel Islands, which have no record of pocket gophers (Thomomys bottae), to mainland sites with high gopher activity to gain some insight into the evolution of plant responses to belowground herbivory. I intend to monitor island and mainland plant responses to simulated root herbivory on both the Santa Cruz Island and mainland sites. I will also use live, captive pocket gophers to determine if island plant forms have reduced their defenses against root herbivory. Diet-choice experiments will be used to compare the palatability of root tissue from island vs. mainland populations. This study has the potential to elucidate the role of belowground herbivores in aboveground plant-herbivore interactions and plant responses to root herbivory on an evolutionary time scale. Resources required: housing for two persons and vehicle use for two days per trip. 4-5 trips per year. My research requires the collection of mature seed (<25% of crop per plant) from several species of plants. In the 2003 field season I will collect the seed of Eschscholzia californica, Hemizonia fasciculata, and, potentially, Lupinus succulentus. The following lists all of the potential field sites for seed collection. If the plants are perennial, seed collection does not damage the perennating portions of the plants and they are able to reproduce in subsequent years. Field treatments would be applied to the following plants: Eschscholzia californica, Hemizonia fasciculata, and, potentially, Lupinus succulentus. The field season would proceed as follows: The Campo Raton populations of Eschscholzia californica and Christi Ranch (near the airstrip) and Willows Canyon populations of Hemizonia fasciculata are suitable for the field treatments I am proposing. Populations of Lupinus succulentus have yet to be located. 30-40 pairs of individuals will be chosen from these populations by matching size. After taking growth measurements I will apply a root damage treatment to one individual of each pair (driving a 5cm wide dutch auger into the ground at a 45 degree angle 15cm from the stem). Two and four months after the treatment I will return to the populations to assess the response in growth, fecundity, and survival. While some individuals may die from the treatment the overall population density will not be heavily impacted. I'd like to apply the treatment to Eschscholzia californica and Lupinus succulentus in late February and to Hemizonia fasciculata in early May. These trips will coincide with seed collection, so estimates on visit dates should remain the same. In addition, I intend to collect 10 plants per population in March and June for chemical analysis.

Visit #867 @Santa Cruz Island Reserve

Approved

Under Project # 769 | Research

The evolutionary response of plants to root herbivory

professional - National Science Foundation

Reservation Members(s)

Sean Watts Feb 13 - 15, 2003 (3 days)
Sean Watts Feb 13 - 15, 2003 (3 days)

Reserve Resources(s) | Create Invoice

Dorm 2 Feb 13 - 15, 2003
Jeep 2 Feb 13 - 15, 2003