Wednesday, February 23, 2011

Tree Tubes: A Dissenting Opinion?

I often visit web forums where tree planting and tree tubes are discussed.  It gives me more insight into the experiences, likes, dislikes, misconceptions and opinions of tree planters - which in turns helps me provide better instructions, develop better products, and in general provide better service.

Wherever people "meet" to anonymously exchange ideas and opinions you never know what you're going to read.  For example, in a discussion board thread about tree tubes on a well-known gardening/landscaping site I came across this, in reference to tree tubes:

"Nasty plastic litter that spoils the landscape and harms wildlife. Often with the remains of a dead tree in the middle."

I wish people would learn not to sugar coat things and would say what they really mean!  There are actually 4 separate aspects of this post, and I'd like to address each one of them separately:

1) Nasty plastic litter.  Yes, tree tubes are plastic.  And yes, if left too long in the field without removing and disposing of them properly they can indeed become litter.  Part of this has been a learning curve.  Foresters were initially told by overly optimistic tree tube manufacturers that the treeshelter tubes would photodegrade into smaller and small pieces that would eventually turn into an inert power... kind of like fairy dust.  Tree tubes do photodegrade, but we know now that they should be removed and properly disposed of after doing their job.

I'll be doing a carbon footprint post soon - a plastic tree tube made from petroleum products that leads to a successful planting the first time, versus the petroleum needed without tree tubes, to grow new seedlings year after year, to prepare the site year after year, to drive to and from the planting site many more times, etc.

2) Spoils the landscape.  Yes, for a brief period of time when tree tubes are used we are forced to look at a field of vertical plastic tubes.  But this statement fails to take into account two things:  The tree tubes are there for perhaps 5 years out of an 80, 100 or 150 year tree rotation.  And, if not for those tubes the view they are "ruining" would look at lot worse for a lot longer, because it would likely be the subject of repeated efforts to clear, site prep and plant.

3) Harms wildlife. On its face this comment seems ludicrous given that tree tubes are helping to create - and re-create - millions of acres of wildlife habitat. They are an integral and necessary component in restoring such wildlife-sustaining trees as the mighty American chestnut in the face of historically high deer populations, hundreds of invasive weed competitors, and in the absence of the climatic conditions and periodic fires that allowed many hardwood trees to get established in the past.  At the "tubular" level this comment might be referring to the tendency of some cavity nesting songbirds, such as bluebirds, to enter tubes - possibly searching for a new nesting site, possibly chasing insects, possibly for shelter, or possibly by accident - and become trapped.  This is why all tree tube suppliers provide plastic mesh caps to place over the top of the tubes until the trees emerge, after which birds no longer enter the tubes.  So to the extent that this was ever a problem, there is now an easy solution.  I'll say it again:  No other tree establishment tool or practice has done more to establish critical wildlife habitat than tree tubes.

4) Often with the remains of a dead tree in the middle.  Over last 21 years I have noticed something interesting in people's perceptions of tree planting success.  Imagine there is a field in which 300 oak seedlings are planted.  The forester decides to use treeshelters on 100 of them.  Now imagine that this planting is in an area with a white tailed deer density of about 40 per square mile, not uncommon in the eastern USA, that there is a drought the summer after the seedlings are planted, followed by a wet year.

Now imagine that you are visiting that site three years later, without knowing how many trees were planted.  What would you find, and what would you think?  You might find a handful of oak trees that survived and grew to waist or chest height without tubes, and you might think, "See, these trees didn't need tree tubes."  And you might look in the tubes and find perhaps 10 or even 20 dead trees.  You might conclude that the tree tubes are an unnecessary  eyesore. 

But in reality, what are you really seeing?  A handful of trees that survived without tubes means that the vast majority did not - killed by drought, eaten by dear or out-competed by weeds.  If all 300 trees had been planted without tree tubes that planting would have been a failure. Tree tubes draw people's attention and scrutiny - they generally walk past (or on) dozens of dead un-tubed seedlings to look down a tube and see how the tree is doing.

10 or 20 dead trees in the tubes means there were 80 or 90 living ones.  And that number likely could have been higher with today's better planting stock and with more aggressive weed control by the planter.  80 or 90 high value oak stems per acre looks an awful lot like success in my book.

Part of this person's opinion - and it's not an uncommon one - is based on the misconception that the project would be as successful, or more successful, without tree tubes.  That would be true,

> if we could go back in time to when there where 500,000 deer east of the Mississippi (instead of 500,000 deer harvested by hunters in WI each year without decreasing the overall size of the herd)

> if we could go back in time to when fire - either wildfires or those set intentionally by indigenous people to manage vegetative cover - helped oaks and other trees gain a competitive advantage over grasses

> if we could go back in time to before hundreds of invasive species of grasses, shrubs, vines and trees started competing with our seedlings from resources

We are not planting trees into a "natural" world, and so we need to use "unnatural" means in order to achieve success. If that means putting up with seeing a "plastic forest" for a few years to get those trees established I think that's not a bad trade off.

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