Starr Tree Root Structures

Starr tree roots also grow normally until they reach the bottom or side wall of the container.  But then the root tip becomes pruned by exposure to air and by dehydration.

The tree responds by activating dormant root buds close to the trunk to produce more lateral roots.  The tree also responds by making root growth along the branch which was air pruned.

When any of these new growing roots reach the container wall, the process is repeated, thereby creating a very fibrous root system.  This root system exists throughout the root ball.  There are no circling roots at the container wall or bottom, and no circling roots can be hidden within the root ball.

As Starr trees are advanced in production to larger containers, root pruning is continued without cutting or chemicals. 

Starr trees have good visible trunk flare, appropriate for the species and age of the tree, because care was taken at the initial planting of the cutting or seeding in the first container and then again each time that tree was replanted in a larger container as it advances in production.

The Four Stages of Starr Tree Growth

Stage 1:  Immediately form lateral roots radiating from trunk.

sample photo

Within days after germination and before a seedling's tap root reaches two-inches, seedlings are individually inspected, selected, and hand transplanted into a cell of a production flat.

Cuttings are similarly individually inspected, selected and hand transplanted.

Plants not meeting our standards for initial root development structures, or initial stem development structures, are discarded.


stage 1 seedling stage 1 seedling washed roots

When the tap root reaches the bottom of the cell it is air pruned.

When radiating roots reach the walls of the cell, they are air pruned.

When the plant responds by creating additional root structures which grow to the cell bottom or wall, they are again air pruned.

The result is a root system that utilizes the entire root ball and there are no circling roots within or at the edges of the root ball.


Stage 2:  Provide more space for fibrous root growth.

When inspection shows that root growth in the cell has produced the desired root structures, but before the roots have fully utilized the interior root ball, the tree is transplanted into a larger container.  The new container's space provides the additional environment needed for continued good root growth.

This process is repeated until the tree reaches its specification size.

stage 1 seedling to be advanced in production

Stage 1 seedling ready to advance to Stage 2.

Please click on the above image to see more detail in a larger picture.


soft fabric containers root prune by trapping root tips in the soft fabric inside wall

Stage 2 Production Containers.
A tree is advanced to a larger container when its roots have almost utilized the space in the existing container.

These containers use root entanglement, at the container's fuzzy fabric interior wall, to create a fibrous root system.

These are above-ground containers, and other containers are used for in-ground production.


plastic container with thousands of air pruning holes

Another type of production container.

This is another above-ground container and it uses air pruning to produce fibrous roots.


large fabric container

Containers can become quite large to support continued growth for larger trees.

Please note the large width to height ratio of the container.

This follows the proportions of tree roots in nature, and it helps the tree to become established quickly in the landscape.


fibrous roots at container wall do not circle

Extremely fibrous root systems  are produced.

Please click on the above image to see these root structures in a larger sized picture.


three weeks growth into new soil

These root systems grow rapidly into new soil when the container wall is removed.

Part of one side of this container's wall was removed, and 6 inches of new soil was added.

In three weeks, the additional soil was probed to show the rapid new root growth.  Click on the image to see a larger picture.


forks lift tree to show free-fall damage to root ball

A tree was removed from its container and loaded on a forklift.


fibrous roots with no circling at container wall

Note the fibrous roots.
Please click on the image to see more detail.

tree experienced a 5-foot drop

The root ball is still fully intact after the tree was dropped about 5 feet off the ground.

Please examine a larger image by clicking the above image.

the root ball is intact held together by its fibrous roots

The very fibrous root system has held the root ball together.

This tree was planted and successfully became established in the landscape.

Starr tree's root balls are so fibrous that no tied burlap or metal support is needed to hold the root ball together.


Stage 3:  Growth to meet the delivery specification.

When tree approaches its desired size, final production methods are then employed to bring the tree to its delivery specification.

Delivery specification may include such items as the customer deems desirable:  delivery date, caliper size, ball weight, anticipated holding time between delivery and planting, transportation stacking method, root ball covering, and anticipated landscape soil conditions.

Oak, 3" caliper

Oak, 3" caliper


Oak, 2.5" caliper

Another oak, 2.5" caliper

Crape Myrtle, multi-stem

Crape Myrtle, multi-stem


Birch, 1.5" caliper

Birch, 1.5" caliper


Stage 4:  Growth and establishment in the landscape.

The fibrous root systems in a Starr tree allow the tree to become rapidly established in the landscape.

These fibrous roots continue to grow outward from the trunk in all directions.  Proper moisture levels must be provided during this establishment period.

With about 6 inches of new root growth at the outside perimeter of the root ball, the tree will no longer depend upon the roots within the root ball for survival and the tree will have become established.

tree spade removed tree from landscape

A large tree spade was used to dig a recently planted Starr tree.

Note the new roots in the landscape soil.

Please click on the image to see a larger image.


tree roots have grown into the landscape soil

A hand shovel was used to remove side soil to show more new root growth into the landscape soil.

Click on the above image to see more detail.

forklift blades rip tree from landscape soil

Here, forklift blades are used to extract a Starr tree planted in the landscape soil the previous year.


tree roots have expanded into the landscape soil

The extracted root ball shows many new roots have grown into the landscape soil.

Because the blades entered the soil close to the right side of the ball, roots there were severed and left in the ground.

Please click on the image to see a larger image.