| Trees of red maple (Acer rubrum L.) were planted into seven
container types evaluated for their ability to reduce number of roots deflected
by the container wall. Seedlings were grown 70 weeks (production phase)
in seven container types to a mean trunk diameter of 3.9cm (1.5 in) and
were transplanted into a sandy soil and grown with frequent or periodic
irrigation for 24 weeks (landscape phase). There was no effect of container
type on total root mass, trunk diameter or height during the production
phase. Total deflected root length was less in low-profile plastic containers,
chemical root pruning containers, air root pruning containers (ARPC), and
wood boxes than in standard black plastic containers (SBPC). Trees produced
in the SBPC had the most horizontally-oriented deflected root length while
the ARPC and the SBPC had the most vertically-oriented deflected root length.
Trees grown in the ARPC had less roots on the inside of the root ball than
all other container types. Container type did not influence root and shoot
growth, but impacted stem water potential in the first five months after
transplanting to the landscape. Trees frequently irrigated during the landscape
phase had greater trunk diameter, height, and generated more new root mass
than those which were infrequently irrigated. |