1 1 Appendix S1 Data sources for competition intensity and reproductive efficiency 2 Table S1. The species, the life history for each species, and the vegetative and 3 reproductive traits recorded for each species used to test the relationship between 4 relative reproductive effort and competition intensity in this study. Where multiple 5 populations or genotypes of the same species were included from a given study, this is 6 indicated after the species name in the table. 7 Species Life History Vegetative size Reproductive Reference allocation Abutilon theophrasti Annual Above ground biomass Seed biomass Mabry & Wayne 1997 Alliaria petiolata Biennial Shoot biomass Total fruit biomass Meekins & McCarthy 2000 Alliaria petiolata Biennial Total biomass Fruit number Meekins & Mccarthy 2002 Alliaria petiolata Biennial Total biomass Seed number Gerber et al. 2007 Amaranthus retroflexus Annual Total biomass Seed number McLachlan et al. 1995 Arabidopsis thaliana (3 populations) Annual Rosette biomass Inflorescence biomass Pagan et al. 2009 Arabidopsis thaliana (2 genotypes) Annual Biomass at age of first reproduction Fruit number Bonser & Ladd 2011 Aristolochia reticulate Perennial Shoot biomass Reproductive biomass Fowler & Rausher 1985 Asclepias syriaca Perennial Vegetative biomass Fruit number Agrawal 2004 Atriplex triangularis Annual Shoot biomass Reproductive biomass Drake & Ungar 1989 Bouteloua gracilis Perennial Blade and sheath biomass Reproductive biomass Jaramillo & Detling 1988 2 Brassica napus Annual Total leaf area Total seed biomass Momoh & Zhou 2001 Bromus tectorum Annual Above ground biomass Seed number Palmblad 1968 Capsella bursapastoris Annual Above ground biomass Seed number Palmblad 1968 Carduus nutans Biennial Shoot biomass Seed number Kok et al. 1986 Cassia fasciculata Annual Above ground biomass Fruit number Lee & Bazzaz 1982 Catanache lutea Annual Aerial biomass Number of capitula Ruiz de Clavijo & Jimenez 1998 Centaurea maculosa Perennial Above ground biomass Flower number Jacobs et al. 2006 Centaurea maculosa Biennial Shoot biomass Seed number Muller-Scharer 1991 Cirsium altissimum Biennial Total biomass Flower number Suwa & Louda in press Cirsium arvense Perennial Shoot biomass Seed biomass Friedli & Bacher 2001 Cirsium vulgare Perennial Vegetative biomass Seed number Suwa et al. 2010 Cirsium vulgare Biennial Total biomass Flower number Suwa & Louda in press Conyza Canadensis Annual Above ground biomass Seed number Palmblad 1968 Cucumis sativus Annual Total leaf area Flower number Bach & Hruska 1981 Danthonia caespitosa Perennial Shoot Biomass Flower number Quinn & Hodgkinson 1983 Echium plantagineum Annual Above ground biomass Seed biomass Sheppard et al. 2001 Eriophorum vaginatum (2 populations) Perennial Above ground biomass Inflorescence number McGraw & Chapin 1989 Eriophorum scheuchzeri Perennial Above ground biomass Inflorescence number McGraw & Chapin 1989 3 Eschscholzia californica (4 populations) Perennial Total biomass Flower number Leger & Rice 2003 Festuca idahoensis Perennial Basal growth Number of flowering culms Huddleston & Young 2004 Hypericum gramineum Perennial Shoot biomass Fruit number Willis et al. 1998 Hypericum cumulicola Perennial Above ground biomass Flower number + fruit number Quintana-Ascencio & Menges 2000 Hypochoeris glabra Annual Rosette biomass Reproductive biomass Fone 1989 Hypochoeris glabra Perennial Shoot biomass Achene number Baker & O'Dowd 1982 Lythrum salicaria Perennial Above ground biomass Inflorescence biomass Notzold et al. 1998 Oenothera biennis Biennial Total biomass Seed number Kromer & Gross 1987 Panicum virgatum Perennial Ramet biomass Reproductive biomass Hartnett 1993 Pectocarya recurvate Annual Number of shoots Seed number Pantastico-Caldas & Venable 1993 Phytolacca americana Perennial Shoot biomass Fruit biomass He & Bazzaz 2003 Plantago lanceolata Perennial Above ground biomass Seed number Palmblad 1968 Plantago major Perennial Above ground biomass Seed number Palmblad 1968 Plantago patagonica Annual Leaf number Seed number Pantastico-Caldas & Venable 1993 Poa annua Annual Total leaf biomass Reproductive biomass Rodriquez & Brown 1998 Polygonella basiramia Annual Above ground biomass Flower number + fruit number Quintana-Ascencio & Menges 2000 Potentilla anserina Perennial Above ground biomass Number of flowers Rautiainen et al. 2004 Pseudoroegneria spicata Perennial Basal growth Number of flowering culms Huddleston & Young 2004 4 8 Raphanus raphanistrum (two populations) Annual Stem diameter Seed number Campbell & Snow 2007 Rorippa austriaca Perennial Above ground biomass Flower number Dietz et al. 2002 Schizachyrium scoparium Perennial Total biomass Length of flowering stalks vanAuken & Bush 1988 Senecio viscosus Annual Above ground biomass Seed number Palmblad 1968 Silene anglica Perennial Above ground biomass Seed number Palmblad 1968 Spergularia marina Annual Vegetative biomass Flower number Ungar 1992 Triplasis purpurea Annual Shoot biomass Seed number Cheplick & Kane 2004 Viola sororia Perennial Total leaf biomass Number of flowers Solbrig 1981 5 9 10 11 12 13 14 References S1 Agrawal, A.A. 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