Start with good roots

Most shade trees begin as seedlings or rooted cuttings. These are propagated in field soil beds, in open trays, or in small propagation trays or small containers. These containers can range in size from one to several inches across. Roots quickly reach the sides of the containers and deflect down or around the pot. If deflected roots are not too large then they can be cut to improve root system quality. Roots of some species in field soil often grow down at a steep angle. Roots directly deeply by propagation practices may not be well suited for urban landscapes. Therefore, focus is on producing at least some shallow horizontally oriented roots in addition to deep roots.

Poor root systems
Good root systems


Tap root circles bottom of propagation pot


 

 

 

 

 

 

 

 

Tap root air pruned and lateral roots are straight.


Lateral roots deflected by container wall are likely to become stem girdling roots later.

 


Lateral roots are straight and not deflected.


Roots form a knot from being deflected in the small propagation container.


Roots growing more-or-less straight out from the stem.

 

 

 


 

 

 

 

 

Roots are deflected down, up, and around the propagation container


Tap root was air pruned and lateral roots are straight and not deflected.


Tap root on this tree in a #3 container spiraled around the smaller propagation container.


Root ball was cut and teased apart when the liner por root ball was planted into the #3 container.


Roots directed mostly downward. (photo courtesy Keith Warren)


Roots growing more laterally and close to surface (photo courtesy Keith Warren).