Moisture stress stimulates the subsequent growth of lignotuberous Eucalyptus maculata seedlings

Summary

Seedlings of Eucalyptus maculata Hook, grown in 20 cm pots were subject to three soil nutrient and three soil moisture regimes with all shoots above the lignotuber detached 76, 282 and 390 days after watering treatments began. Subsequently, all treatments were standardised (i.e. fertilised and maintained near field capacity) for 84 days, when the shoots were detached for a fourth time. Before standardisation, lignotuberous seedlings from the drier treatments grew poorly. However, after standardisation seedlings from the drier treatments grew significantly better than all other treatments.

Lignotuberous E. maculata seedlings may benefit from exposure to environmental stress before conditions become more favourable for growth. This preconditioning effect may strengthen the vigour of the eucalypt lignotuber and improve the seedling's capacity for survival under some field conditions. The results are discussed in relation to the response of E. maculata regrowth over a topographic gradient in south coast forests of New South Wales.