Root attributesz eight months after root pruning 57 L container root balls when planted into landscape soil.
| Root pruningy | 57 L visual imprintx | % circumference circled at position of 57 L container wallw | No. roots >5 mm diameter deflected by 57 L container wall | % circumference without roots >5 mm diameter 5 cm beyond 57 L wall position | Radial root ball symmetryv (1–5) | No. radiating straight roots trunk to beyond 57 L wall positionu |
|---|---|---|---|---|---|---|
| Yes | 1.5 bq | 4 b | 1 b | 22 b | 4.0 a | 15 a |
| No | 4.4 a | 59 b | 16 a | 58 a | 1.8 b | 4 b |
| Root pruning | % five largest roots grew into soilt | Total no. roots grew from entire 57 L root balls | No. roots grew from top half of 57 L root balls | Total root CSA (mm2)r | Ratio root CSA from top: bottom half of root ball | |
| Yes | 58 a | 27 a | 18 a | 862 a | 2.3 a | |
| No | 22 b | 12 b | 7 b | 311 b | 1.3 b | |
↵z Root characteristics measured within a hand dug, shoved-excavated, cone-shaped soil volume 60 cm in diameter and 60 cm deep centered on the trunk.
↵y Trees were root pruned by shaving away the outer 3 to 4 cm periphery of the 57 L root ball when planted into the landscape.
↵x Visual rating of root deflection severity at 57 L container position with 1 = little imprint or retained “cage” formed by deflected roots, and 5 = strong imprint formed by deflected roots retaining the shape of the container).
↵w Percent trunk circled with roots >5 mm diameter at the position of the periphery of the 57 L root ball.
↵v Visual rating with 1 = radially asymmetrical distribution of roots with most on one side of root ball, and 5 = radially symmetrical distribution of mother roots (roots growing directly from stem).
↵u Number of roots >3 mm diameter measured 5 cm beyond the position of the 57 L container wall that grew from trunk at <45 degree angle to substrate surface without making a turn of >60 degrees relative to parent root azimuth at trunk.
↵t Percent of the five largest diameter roots (diameter measured just beyond root collar) that grew beyond the periphery of the 57 L container position following the largest root at forks.
↵s Roots >3 mm diameter measured 5 cm beyond 57 L periphery.
↵r Root cross-sectional area (CSA) measured 5 cm outside 57 L root ball position for roots >3 mm diameter growing from entire root ball periphery.
↵q Means in a column with a different letter are statistically different at P < 0.0002; n = 20, averaged across propagation and nursery container types due to insignificant interactions.