PARENT SESSION
Poster Session #36: Seed Production, Recruitment, and Pollination.
Wednesday, August 7. Presentation from 5:00 PM to 6:30 PM. Exhibit Hall B & C, TCC

Comparisons of male and female reproductive effort in temperate tree species.

LaDeau, Shannon^*,1, Clark, James¹, ¹ Duke University, Program in Ecology, Durham, NC

ABSTRACT- Reproductive ecology is poorly understood for many temperate tree species growing in natural forest stands. Specifically, there are few studies that look at male reproductive effort in temperate species and a paucity of research comparing male and female effort. We analyze and compare pollen rain and seed rain over five forested sites located along an elevational gradient at Coweeta Hydrological Laboratory. Pollen and seeds were collected monthly from "traps" located across mapped forest stands. Preliminary data analyses demonstrate that Acer rubrum pollen and seed production do not vary together at the five sights. In fact, the one site with the highest seed production has the lowest pollen production. Seed rain is more tightly correlated with total basal area of Acer rubrum within a radius of 20 meters than is pollen rain (.93 vs. .44). However, when considering total basal area within a 100 m radius, both pollen and seed rain are similarly correlated with basal area (.77). Liriodendron and Pinus data demonstrate similar patterns. These data represent a novel approach to looking at reproductive effort in closed forest stands that can accommodate spatial and temporal comparisons. These comparisons are especially important in understanding temporal and spatial variations in seed crops and recruitment success and are integral to forecasting forests response to climate and landscape changes that may disproportionately affect male and female reproduction.

KEY WORDS: pollen, dispersal, gradient, reproductive effort