Sprouting success of shrubs after fire: height-dependent relationships for different strategies

Abstract

The sprouting success of co-occurring populations of shrub species in a temperate woodland of semi-arid Australia was investigated and related to population survival strategies. Straw was added to 21 × 15 m plots in the woodland, burnt and the pre-fire characteristics of shrubs were used to determine the basis for sprouting success. Species differed widely (4-94%) in sprouting success; a high percentage of established seedlings of all species were killed by fire but survival increased with height reaching a maximum at 25-60 cm (depending on the species). Thickness of bark at stem bases increased with height growth but sprouting success was not related to bark thickness; sprouting success of shrubs at similar thickness varied greatly between species. All species were able to initiate sprouts after cutting through their basal stems, so lack of active meristems was not a limitation. Species differed in the height at which shrubs began flowering but this was always after maximum sprouting success was reached. It is proposed that differences between individual shrubs in supply of nutrients, carbohydrates, and/or water to activated meristems would account for patterns of in ter- and intra-specific sprouting success. The data are consistent with recognised fire survival strategies. `Sprouters', the species relying more on sprouting than recruitment for population persistence, maintained maximum sprouting success with height growth and gained sprouting ability along stems once they reached 1 m in height. In contrast, `non-sprouters', the species largely relying on recruitment from seed to maintain populations, were either not able to sprout after seedling establishment or steadily lost the ability to maintain sprouts with growth beyond 60 cm and did not develop axillary buds along stems at any height.

Post-fire vegetation recovery in Portugal based on spot/vegetation data

“…Fire usually destroys or depletes vegetation rapidly, in contrast to fire recovery that is a long-term process. Some of the plant communities in the Mediterranean ecosystems, known as resprouter species, have high elasticity after a fire because they are often able to regenerate by means of resprouting from fire resistant structures (López-Soria and Castell, 1992;Hodgkinson, 1998). Other species, the so-called obligate seeders, rely on the germination of fire protected seeds stored in the soil or in the canopy (Lloret, 1998;Arianoutsou and Ne'eman, 2000).…”

Post-fire resprouting ability of 15 non-dominant shrub and tree species in Mediterranean areas of NE Spain

“…Many Mediterranean plant species exhibit the ability to recover readily after fire, either through the germination of pro-* Corresponding author: Anselm.Rodrigo@uab.es tected seeds stored in the soil seed bank or in the canopy [24], or by resprouting from aerial or subterranean fire-resistant buds [17,21,26,38]. The resprouting ability of some of the most dominant tree and shrub species in the Mediterranean Basin is well known (e.g.…”

Integrated shrub management in semi-arid woodlands of eastern Australia: ground and aerial application of defoliant to shrubs regenerating after disturbance

“…Mature plants of budda (Eremophila mitchellii) also have the capacity to coppice from a lignotuberous rootstock following fire (Beeston and Webb 1977;Hodgkinson and Beeston 1995). Mature trees of this species, however, are often more vulnerable to fire (Hodgkinson 1998). At 'Mount Oxley' where budda had been decapitated at ground level by bulldozing, budda coppiced relatively freely from what appeared to be adventitious buds in the surface root system ).…”

“…More effective strategies include integration of 2 or more treatments applied sequentially at critical stages in the shrub regeneration cycle Scifres 1986). Small-plot experiments using artificial fuel have demonstrated that 2 or more fires applied annually can significantly reduce shrub populations, especially when follow-up fires are applied in the autumn (Hodgkinson 1998;Noble 2001).…”