FECUNDITY AND SIZE RELATIONSHIPS IN JACK-IN-THE-PULPIT,ARISAEMA TRIPHYLLUM (ARACEAE)

Arisaema triphyllum is a gender-labile woodland herb in which sex expression is correlated with the abundance of stored resources. Larger plants are female or monoecious, smaller ones are male. Among females larger plants produce more flowers, fruits and seeds, and the rate of successful fruit and seed formation is greater for plants of greater ht and corm diam. Average seed wt is greater in larger plants. Seed number per fruit and average seed wt per fruit taper towards the top of the infructescence. Pollinator limitation and resource supply may both contribute to the regulation of yield; their effects can be interpreted sequentially.