Mast Production in Southern Florida: Literature Review and Recommended Monitoring Methods

Burch, James; Snyder, James

Mast is an Old English term that refers to “nuts used as food’ (Austin, no date). Kelly (1994) summarized definitions of masting as “synchronous highly variable seed production among years by a population of plants”. Lalonde and Roitberg (1992) indicated that masting behavior in plants is generally explained as avoidance of seed predation, but that this does not explain the initial evolutionary development of this activity. Koenig et al. (1994) outlined four major hypotheses that relate to the evolution of masting: 1- Resource matching. Mast is related to the availability of a limiting resource, probably weather, but pointed out that large seed crops should occur during successive years during which conditions are favorable. 2. Predator satiation. Seeds escape predation by numbers. 3. Enhanced pollination success. Concentrating airborne pollen enhances successful pollination. 4. Attraction of seed dispersers. This should result in high seed production of some individuals in the population each year to maintain disperser populations, rather than synchronous, population-wide variations in seed production. This is essentially the opposite of predator satiation hypothesis, as synchronous production of large seed crops for dispersal organisms would have the same effect on them as the effect it would have on the predators. Lalonde and Roitberg (1992) mentioned that masting may also increase populations of predators that will affect competition during following seasons. Work by Koenig et al. (1994) and Shibata et al. (1998) supports the ideas of optimal wind pollination and predator satiation in acorn production. Nilsson and Wastljung (1987) found more successful seed set in mast years than non-mast years for beech trees; as beech are self incompatible, this provides a direct measure of successful pollination. Kelly and Sullivan (1997) found evidence to support predator satiation and optimal wind pollination in a grass in New Zealand.