Plant Growth Regulator for River Birch Trees

River birches are on the short list of trees that occasionally require iron injection to overcome a lack of iron absorption from Lincoln soils.  They are similar to pin oaks in this respect.  As with pin oaks, the use of a growth regulator enhances the effects of iron injection:

River birch is a popular planting in Lincoln owing to a tolerance for problematic soils, an excellent storm survivability due to an outstanding flexibility in stems, and lastly and mostly, a phenomenal rate of growth.  While this means that a river birch planted now can achieve shade for your home or lawn much faster than with any other tree, it comes at the expense of a limited lifespan compared with other trees.  At around the 20 year mark, river birches achieve stature as “mature” plantings and suddenly the homeowner is faced with “big tree” problems.  These trees do not stop “growing fast” at this juncture, and trimming becomes costly!

This is where the technology of plant growth regulators comes into play.  “Paclobutrazol,” marketed as Cambistat® and Short Stop® is a chemical that is injected into the soil at the base of tree at three year intervals to be taken up by the roots.  This product acts on the hormone level to slow top growth by 50%, with the added benefit in the response of the tree to instead direct energy into the development of greater root density.  Slower top growth and means less trimming expense for your fast growing river birch, with more robust rooting to overcome nutritional stresses.  Notably, river birch commonly suffer from chlorosis (yellowing of leaves) due to inability to absorb iron from Lincoln’s soils.  In the final analysis we have a treatment option that is nothing short of a magic potion for river birch trees since river birch are both too fast growing and universally deprived of optimal nutrient uptake.

Ideally, growth regulator treatment is commenced as soon as your river birch tree has grown enough to provide the substantial shade or privacy which informed the need to plant it in the first place–often around the 10 year mark.  Older trees are “huge,” they may already be getting close to being more expensive to keep trimmed than the value they add to your property, and the dosage required for treatment is large so the price is high.  “The horse has already left the barn” so to speak….

Please call or text today with your questions or to schedule application of plant growth regulator and iron injection.

Will Frerichs, 402-476-0499