The Biology of Tuart

The biology of Tuart has received little attention. Existing known studies, including work by the authors, are used to look at aspects of Tuart’s reproductive biology, phenology, seed bank dynamics arid seedling recruitment, as well as the effects of fragmentation and fire on Tuart populations. The studies of Tuart’s reproductive biology and phenology have found that flowering occurs from January to April with reports of mass flowering occurring every five to eight years and patchy flowering occurring intermittently. Seed production and supply in Tuart may show considerable temporal variation. A diverse array of insects and birds are most likely to be involved in pollination of Tuart. Research currently on the seed bank dynamics of Tuart has observed that on average four seeds are stored in each woody fruit for up to two seasons. As a consequence, seed storage in the canopy may be high when heavy flowering seasons occur. Seeds are normally slowly released from the canopy, but can also be released en masse following disturbances such as fire. Tuart seed is susceptible to predation by ants that can remove a large proportion of seed in the soil quickly and hence, Tuart seeds do not form a long-lived soil seed reserve. Seeds have high viability (86%) and no innate dormancy. Mass recruitment of seedlings following fire occurs as the seeds swamp the predators. Fragmentation and changed disturbance regimes are affecting many remnant Tuart woodlands, transforming community structure and species composition. There is evidence to suggest that Tuart is declining in urban remnants. Tuart flowering is patchy, in time and space, and therefore the size of the canopy seed store may vary considerably between years. Studies in remnants indicate that it takes some time for a Tuart population recovering from fire to become reproductive. If a fire occurs before this time, it is unlikely that adult trees will have a canopy seed store available for synchronous seed release following a fire to establish new trees. Mature Tuarts are regularly killed by fire when the fire breaches the bark and establishes in the wood. It is also been suggested that in urban remnants the abundance of naturally occurring wood boring insects may have increased as a Consequence of their natural predators declining in numbers. This increased abundance of wood boring insects may be causing increased mortality in Tuart populations. Similar suggestions have been advanced for pathogenic fungi, such as Armillaria. Some suggestions for future investigations to improve knowledge to aid in the management of Tuart in remnants are listed.

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