| Irrigation volume had no effect on post-transplant trunk
diameter growth, crown spread, height growth, or stem xylem potential of
Quercus virginiana (live oak) in the first 27 months after transplanting.
Container-grown trees irrigated infrequently after transplanting grew more
slowly than those irrigated frequently and more slowly than field-grown
trees. This resulted from increased water stress on container trees that
were infrequently irrigated. Post-transplant growth of trees from a field
nursery was not affected by irrigation frequency. Three of 30 trees on the
infrequent irrigation schedule, which were transplanted from containers,
died the 1st time irrigation was cut back from twice each week to once a
week 7 weeks after transplanting, and new, nonlignified shoot and leaf tissue
on most other container trees dried up. No trees transplanted from the field
nursery died, nor did new growth wither. The 1st year after transplanting,
trunk diameter of trees collected from the wild increased more slowly than
those of trees transplanted from containers or from the field. However,
growth of trees from containers increased more slowly than for trees from
the other 2 production methods during the 2nd and 3rd year after transplanting.
During the first 27 months after transplanting, trunk diameter and tree
height increased faster on small-sized nursery trees of live oak than on
large-sized trees. Rate of trunk diameter growth for container trees slowed
the 2nd growing season on large-sized container trees, perhaps because roots
were not fully established in landscape soil. Frequently irrigated trees
established more quickly than those receiving infrequent irrigation. |