growth, and absence of discolored or damaged leaves ( Brand and Leonard, 2001 ). There is little evidence that indicates consumers pay attention to root ball condition at purchase, yet landscape establishment is affected by the condition of root systems
Sudeep Vyapari, S.M. Scheiber, and E.L. Thralls
Edward F. Gilman, Thomas H. Yeager, and Diane Weigle
Dwarf burford holly (Ilex cornuta `Burfordii Nana') fertilized with N at 22.1 g per container yearly during production in the nursery generated more new shoot weight but less root weight after transplanting to a landscape than those receiving N at 14.8 g per container yearly. Slicing the root ball at planting, compared to not slicing, resulted in comparable regenerated root weight but reduced new shoot number, new shoot dry weight, and new shoot:regenerated root dry-weight ratio when irrigation was not applied daily after transplanting. Although irrigation frequency did not impact total weight of regenerated roots into landscape soil, more roots grew from the bottom half of the root ball when plants were irrigated periodically after planting than when plants received daily irrigation. Plants irrigated other than daily produced fewer shoots and less shoot weight than those receiving irrigation daily after transplanting. When plants were without irrigation for 4 or 6 days in the first week after transplanting, those planted without the nursery container on the root ball were more stressed (more negative xylem potential) than those planted with the container still on the root ball. However, 2 weeks later, plants without the nursery container were less stressed due to root growth into landscape soil.
Sloane M. Scheiber, Richard C. Beeson Jr., and Sudeep Vyapari
Root ball slicing is often recommended for root-bound woody ornamentals to promote new root development during establishment in the landscape. It is a common practice among gardeners, but not necessarily landscapers, to disrupt root-bound annuals during transplant. However, little if any evidence exists for such practices. Therefore, this study evaluated the effect of root ball condition of annual bedding plants on landscape establishment and growth. Begoniasemperflorens were transplanted from 0.72-L (#1) containers into field plots in an open-sided clear polyethylene covered shelter and managed with Best Management Practices. Three root ball conditions were evaluated: non root-bound (6-week-old plants), root-bound (10-week-old plants), and root-bound with the bottom 1 cm of the root ball removed. Shoot and root dry masses and growth indices were collected weekly for 12 weeks and evaluated relative to root ball condition by linear regression analysis. Nonroot-bound plants had significantly greater biomass, growth indices, height, and root dry weights than the other treatments tested. No significant differences were found between root-bound and manipulated root-bound plants for any parameter examined. The data indicate that the practice of disrupting root-bound plants has no benefit on establishment or growth of annual bedding plants in the landscape.
J. Roger Harris and Susan D. Day
depth affected growth in the nursery of only one of five species tested. In Fare's study, roots had completely filled the container, creating a solid root ball with structural roots buried. The post-transplant consequence of buried structural roots
Abby B. Griffin, Amy N. Wright, Kenneth M. Tilt, and D. Joseph Eakes
( Costello and Paul, 1975 ; Nelms and Spomer, 1983 ). This could be attributed to water loss from the original root ball as a result of absorption by roots, evaporation from the soil surface, and movement of water from the root ball into the backfilled soil
Albert Liptay and Diane Edwards
Roots of tomato (Lycopersicon esculentum Mill.) seedlings grown in multicelled trays were confined largely to the interface between the growing medium and the inner surface of the cell. Because of the predominance of roots in this area, experiments were done in prototype cells to relate seedling growth to change in this interface area while retaining a constant volume. The cell shapes that were tested included a square cell with 1.36-cm sides and other rectangular cells. All cells were 3 cm in height, but widths decreased incrementally by 0.1 cm from the 1.36×1.36-cm square to rectangles with inner cell dimensions of 0.36×5.14 cm. With these changing shapes, the interface area increased but cell width decreased to a more narrow cell. Seedling height increased as the cell shape was changed from a square (1.36 × 1.36 cm) to an elongated rectangle (1.74 × 1.06 cm). More narrow cells caused seedling height to decrease; the shortest seedlings occurred in 0.36 × 5.14-cm cells. Root growth was unaffected by change in cell shape. The smoothness of the inner cell surface, however, affected root growth; a rough texture resulted in stubby and reduced root growth but had no effect on shoot growth.
Richard C. Beeson
or near 100% container capacity, whereas PAW may be critically low within the actual root ball. PAW can be found by first recording the mass of a plant/container with a saturated substrate from which excess water has been allowed to drain. The plant
Julie Guckenberger Price, Amy N. Wright, Robert S. Boyd, and Kenneth M. Tilt
transplanted, it may be difficult for the plant to compensate for evapotranspiration from these abnormally large canopies using only the resources available in the root ball, whereas at the same time allocating energy to root growth. In such difficult growing
Donald R. Hodel, A. James Downer, and Dennis R. Pittenger
—resulting in instant, mature landscapes. In contrast, the woody, branched root systems of dicotyledonous and coniferous trees require that a much larger root ball be secured to ensure establishment of these types of trees, increasing the difficulty and expense
W. Todd Watson
Studies have demonstrated that the size of transplanted trees has a measurable impact on establishment rates in the landscape. Larger trees require a longer period of time than smaller trees to produce a root system comparable in spatial distribution to similar sized non-transplanted trees. This lag in redevelopment of root system architecture results in reduced growth that increases with transplant size. Research has demonstrated that smaller transplanted trees become established more quickly and ultimately result in larger trees in the landscape in a few years. Additional studies dispute these findings. This paper provides a review of current research on the effect of tree size on transplant establishment.