Regulate Tree Growth

Rainbow Treecare

What is Cambistat?

Cambistat is the newest tree growth regulator with the active ingredient paclobutrazol. It is highly effective at reducing the growth rate of trees over a three year period, and thus is an excellent method of reducing tree maintenance costs. Extensive research and field trials have also shown that indirect effects on growth regulation can provide numerous health benefits for trees. By reducing the amount of energy allocated to shoot growth, more energy/carbon/substrates are available for other uses. Research has shown trees treated with Cambistat have the following responses:

  • Tree growth rate is reduced between 40 – 60 % for three years with one treatment of Cambistat®.
  • Root system enhancement
  • Improve drought and heat resistance
  • Higher tolerance to disease
  • Increase health and longevity

*Courtesy Rainbow Treecare

Cambistat® is a soil-applied tree growth regulator that reduces tree growth 40% to 60% over a three year period.

Cambistat Increases the Lifespan and Durability of Yard Trees

Cambistat works by making the tree more conservative. Slower growth rate means energy is shunted into increased root mass, increased defenses, thicker leaves, and increased storage. A slower growing tree needs fewer resources – including water, minerals and energy. This reduced resource need raises the threshold of stress needed to injure the tree. For many mature yard trees, the deficiency level of the growing site is already past this stress threshold. By reducing the tree’s growth rate – health and longevity can be restored.

*Courtesy Rainbow Treecare

Stimulating Fibrous Root Growth

Re-directing Excess Energy

When Cambistat reduces the growth rate of the tree, it frees up energy, carbon and other substrates that would have been used for that growth. These get shunted back into the tree and are available for use for other functions. One of the responses by the tree is an increase in fibrous root growth.

*Courtesy Rainbow Treecare

Cambistat increases fibrous root growth, but decreases woody root growth

Root to Shoot Ratio

A major issue with trees growing in lawns and other urban sites is a poor root to shoot ratio. This basically means that compared to trees growing in more natural settings, there is more top growth as compared to fibrous roots. This has obvious repercussions that lead to trees that are more prone to stress. By reducing the top growth and increasing the fibrous root growth, applying Cambistat will increase this important ratio.

Linden on the right was treated in 1992 to keep it out of the powerlines. The untreated tree was across the street

*photo courtesy of Dr. Bill Chaney – Purdue University

Where Do Arborists Use Cambistat?

Cambistat is used in many situations. Here are some examples.

  • Increase time needed between prunings
  • Enhance root development in chlorotic trees
  • Stimulate root growth when roots are severed
  • Stabilize slow declining trees
  • Improve defense to certain diseases
  • Maintain trees near buildings
  • Reduce growth of trees near power lines
  • Extend longevity of trees in sites with limited resources
  • Enhance durability and longevity of mature trees
  • Improve durability of transplanted trees over 4″ in diameter
  • Help preserve trees after construction injury
  • Pre-stress conditioning before construction, drought, etc.
  • Minimize damage caused by drought to weakened trees

To discover more about the brilliance of Cambistat follow this link:

Have more questions about Cambistat? Just fill out this form or call our number below.

Return to Tree Tips

Comments are closed.