Root cross-sectional area (CSA), root number, root diameter, and tree subsidence on Cathedral Oak live oak, three growing seasons following planting.
| Planting treatmentz | Trunk caliper when pulled (cm) | Total root CSAy (cm2) | Root CSA (cm2)/cm2 trunk CSAx | Total root no.w | Root no./cm2 trunk CSA | Root diameterv (mm) | Root diam. (mm)/cm2 trunk CSA | Diameter (mm) of 10 largest roots | Tree subsidenceu (mm) |
|---|---|---|---|---|---|---|---|---|---|
| 57 L container | 85c | 20.1bt | 0.34bt | 36ct | 0.62abt | 7.3bt | 0.13at | 12.8bt | −5 (−22 to +3)c |
| 170 L container/ not sliced | 113b | 27.7b | 0.27b | 55b | 0.54b | 6.7b | 0.07b | 14.1b | −2 (−13 to +5)b |
| 170 L container/ sliced | 115b | 25.9b | 0.24b | 55b | 0.52b | 6.7b | 0.06b | 13.5b | −3 (−13 to +3)b |
| Field grown | 132a | 105.6a | 0.69a | 115a | 0.76a | 8.3a | 0.06b | 25.4a | +2 (−5 to +16)a |
↵z57 L container = 29 mm caliper trees from 57 L container; 170 L container/not sliced = 67 mm caliper trees from 170 L container with no root ball slicing at planting; 170 L container/sliced = 67 mm caliper trees from 170 L container with root ball sliced top to bottom in 6 places at planting; field grown = 80 mm caliper trees dug from field soil, all planted March 2005.
↵yTotal CSA of roots >3 mm diameter growing into landscape soil from the top 25 cm of root ball measured 5 cm beyond edge of root ball.
↵xTrunk CSA measured 15 cm from ground.
↵wTotal number of roots >3 mm diameter 5 cm beyond the edge of root ball.
↵vMean diameter for roots >3 mm diameter growing into landscape soil from the top 25 cm of root ball measured 5 cm beyond edge of root ball.
↵uMean (and range) subsidence (−= tree sunk lower into ground; += tree lifted out of ground) three growing seasons after planting on 30 trees per treatment; means in a column followed by a different letter are statistically different at P < 0.05.
↵tMean of seven trees per treatment; means in a column followed by a different letter are statistically different at P < 0.05.