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Soil compaction

Propagation through cuttings

Community tree plantings

Magnolia grandiflora

Horticultural tips

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Mulch and restoration factsheet

Root inspection

Shoot inspection

Sequoiadendron giganteum

Pacific madrone

The myth of soil amendments

Compost tea


Sustainable Horticulture

Crown and Trunk Inspection


Prior to purchasing plants, it is vital to inspect them for serious problems. If you are buying large quantities of a species, inspect a representative sample. Plants that have life-threatening injuries or problems should not be purchased. The following are some things to look out for when buying a plant.

To ensure the trunk and crown are healthy, check for the following:

  • Good height to caliper ratio – taller plants should generally have thicker trunks
  • Good trunk taper – if no taper is visible, the plant was probably planted too deeply

buried trunk

This plant was buried too deeply, as evidenced by the lack of trunk taper above the soil line.

  • Even branch distribution
  • Normal growth pattern for the species
  • No serious pest or disease damage
  • Trees and shrubs should not be topped (hydra growth of numerous shoots from just below a cut is indicative of topping)

topped tree

A topped plant. Topping leads to the growth of many small, unstable branches a short distance below the pruning cut, as seen here.

  • No other improper pruning cuts, such as flush cuts
  • No bark injuries – in B&B plants (balled in burlap), peel back the burlap to ensure it hasn’t been left on so long that the trunk is rotting underneath

rotting trunk

This tree's trunk is starting to rot because it was buried under the burlap too long.

  • Good vigor
  • No watersprouts or suckers


The small shoots growing from the soil are suckers and are indicative of stress; numerous skinny branches (generally growing straight up) above the soil or graft line are known as watersprouts

  • Stability—able to stand on its own with temporary or no staking
  • Soil not overly dry or wet—no signs of desiccation or anoxia
  • If the plant is grafted, make sure the graft is not failing

failed graft

A failing graft; the two pieces of plant did not grow together well, leading to an unstable stem that will likely break at some point in the future.

  • The correct species is supplied