E.F. Gilman
Plant form in relation to root spread
Journal of Environmental Horticulture 7 (3): 88-90
Four Juniperus chinensis cultivars, 'Torulosa', 'Sylvestris', 'Pfitzeriana' and 'Hetzii' had mean and maximum root spreads of 1.6 m (4.8 ft) and 2.2 m (6.6. ft) resp, 12 months after planting. Despite large differences in plant form, root spread on all four cultivars was equal. The columnar cultivar 'Torulosa' had significantly less root length within the drip-line than the more spreading cultivars 'Pfitzeriana' and 'Hetzii'. Percentage of total root length within the dripline was correlated (r= -0.72) with the ratio of plant height to spread.
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