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ambience: digging
City dwellers know the challenge of transforming a small space into a home that accommodates their needs. Well urban trees face the same problem and city foresters tackle it before they start digging. I’m Jim Metzner and this is the Pulse of the Planet.
“The whole process of tree establishment is one of making decisions and knowing what the site is like first, and we call that process site assessment.”
Nina Bassuk is a professor of Urban Horticulture Institute at Cornell University she has been transplanting trees in cities using the bare-root technique.
“The difference in the way we plant trees bare-root is that we prepare a wide, fairly shallow site for the tree. Tree roots don’t grow down like the mirror image of the top parts of the tree. They grow shallowly within the first twelve to twenty-four inches or even three feet of the surface. So we only dig a hole which is about twelve to eighteen inches deep, depending on the root system, and we provide it quite a wide site, so that those roots can continue growing horizontally like they like to do.”
When it comes to figuring out the depth of the hole bare-root planting has a distinct advantage over planting balled and burlapped trees.
“Another good thing about bare-root planting is we can see where the trunk meets the root-flare. We wanna plant at that same level. If we plant too deep, the tree doesn’t often get off too a good start. So we wanna plant at the right depth, at the same level where the plant was growing in the nursery.”
Recent improvements have made bare-root planting an even better idea.
“Our twist to it is instead of having the roots totally bare, we actually dip them in a hydro-gel, a slurry, which help the roots stay moist for, oh, seven to ten days. Otherwise they would just dry out and we couldn’t use this method.”
Pulse of the Planet is presented by DuPont bringing you the miracles of science for 200 years, with additional support provided by the National Science Foundation. I’m Jim Metzner.
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