Mg. Messina et Je. Duncan, IRRIGATION EFFECTS ON GROWTH AND WATER-USE OF QUERCUS-VIRGINIANA (MILL) ON A TEXAS LIGNITE SURFACE-MINED SITE, Agricultural water management, 24(4), 1993, pp. 265-280
Three different irrigation regimes (100%-high, 67%-medium and 33%-low
of estimated well-watered conditions) were applied to Quercus virginia
na (live oak) seedlings on reclaimed lignite surface-mined soils in ce
ntral Texas as a means to study the physiology and growth of seedlings
during establishment. The study period was 4 July 1990 through 30 Sep
tember 1990. Transpiration, stomatal conductance and water potential w
ere significantly higher (alpha=0.05) in the high treatment than in th
e low and medium treatments. Favorable water status contributed to som
ewhat greater seedling growth in the high treatment than in the low an
d medium treatments. Greater growth was associated with favorable seed
ling water potential, high stomatal conductance and rapid transpiratio
n in the high treatment. Physiological responses and growth characteri
stics indicated that an irrigation rate of 1.2 kg.d-1 per seedling dur
ing the dry summer months was sufficient for seedling survival and est
ablishment. An irrigation rate of 3.8 kg-d-1 per seedling promoted rap
id seedling growth in addition to ensuring establishment.