Botany Department, University of British Columbia, Vancouver, B.C. V6T 1Z4, Canada. msbarker@indiana.edu|Botany Department, University of British Columbia, Vancouver, B.C. V6T 1Z4, Canada. msbarker@indiana.edu|Botany Department, University of British Columbia, Vancouver, B.C. V6T 1Z4, Canada. msbarker@indiana.edu|Botany Department, University of British Columbia, Vancouver, B.C. V6T 1Z4, Canada. msbarker@indiana.edu|Botany Department, University of British Columbia, Vancouver, B.C. V6T 1Z4, Canada. msbarker@indiana.edu