I saw an article on Yahoo this morning about the city of Baltimore planting “Super Trees” in their parks. My first thought was “Oh No!!!, here comes the mad scientists playing around with genetic engineering, but after some research I found that was not the case. It is true that these “Super Trees” are better than your average nursery grown tree but not because of some crazy bioengineer in a lab somewhere cutting and splicing genes into Frankenstein trees. These trees are better because of improvements in good old horticultural practices. Here’s a quote from the Parks and People website (underlines by me):
The Root Production Method (RPM) is a natural process found to positively affect trees, shrubs, and grasses, resulting in accelerated growth, increased root mass, early flower, fruit, seed, and/or nut production, and higher rates of establishment and survivability.
RPM is composed of a series of horticultural practices including: collection of superior native seed stock, air-root pruning, greenhouse growing, acclimating to local conditions, balanced nutrition, soil microbial and fungal relationships, container growing in special media, and timing learned from over 20 years of field research.
In my opinion the big factor in these stronger trees is the use of “Air-pots”. Air pots are a fairly new product that several wholesale production nurseries are now utilizing. These pots rely on air pruning to keep roots from circling the pot. The walls of the plastic containers are very porous and let air contact the roots, in affect killing the root tip as it reaches the edge of the container, thus forcing side shoots and a denser root ball. It is pretty amazing to see the difference in growth rate once these plants are planted into the ground. The really explode due to these massive healthy roots.
Here in Florida hurricanes are a big deal and many municipalities are now requiring that trees must be purchased from nurseries that utilize these techniques because stronger roots means fewer trees to pick up after a storm.
Of course agressive tree roots can become a problem too. Checkout the photos on this site.
No Brown Thumbs