Thursday, December 30, 2010

Where did tree tubes come from?

To the casual observer (forestry contractor, tree farmer, conservation district manager, etc.) it must seem like tree tubes (aka treeshelters) went from being a novelty to suddenly being all over the internet in the last few years.  Many of these folks are probably asking themselves, where did tree tubes come from, and why are they suddenly "all the rage" in tree planting?

Here's a quick history, from someone who's been a part of it almost from the beginning.

Translucent plastic treeshelters were originally developed in the UK starting in 1979 by a British Forestry Commission Forester named Graham Tuley.  In his honor they were originally - and in many places still are - called Tuley Tubes.  The problem Mr. Tuley was trying to solve was common then and has become an epidemic now:  Unchecked deer populations wiping out any and all attempts at hardwood reforestation.  His solution?  Use a translucent plastic tube to provide "safe passage" for the tree seedling to grow up past the level of deer browse.  Naysayers thought these "mini greenhouses" would overheat and kill the trees.  The opposite was true:  It was found that tree shelters dramatically reduce moisture stress, and therefore increase survival rates and dramatically accelerate early growth.

Fast forward to 1989, when treeshelters were introduced to the USA for the first time.  If anything, the need for tree tubes was even greater in the USA given the record numbers of white tailed deer (the 1900 population of deer in the USA is estimated at about 500,000; today we have states where that many deer are killed by hunters each year without any appreciable effect on herd numbers).  However, two factors combined to retard the acceptance of tree tubes in their first 15+ years in the USA:

1. Perception high cost - Tree tubes were seen as being "too expensive," but it took some time before we all came to grips with part 2 of that statement: "compared to what?"  Yes, tree tubes are expensive compared to the way we used to do things: plant a bunch of seedlings, walk away, deer eat the seedlings, repeat.  In other words, tree tubes are expensive as compared to failure.  In recent years, however, more and more foresters and tree planters have gained a better understanding of the economics involved.  Now the prevailing thinking is, "Tree tubes reduce the cost of successful reforestation."  When you take into account everything that goes into successfully establishing hardwood trees, and compare the cost of tree tubes to that, then you begin to see all of the ways tree tubes save money:  Ability to plant fewer stems to achieve the same stocking level.  Virtually zero replanting due to mortality.  Fast and easy weed control.  And, as always, protection from deer (and their "partners in crime" rabbits).

2. Problems with tree tube performance - Depending on their location, early adapters of tree tubes in the USA experienced difference versions of the same story:  Elation at the initial survival, rapid growth and browse protection provided by treeshelters, followed by disappointment over some later problem or side effect.  In northern climates it was winter die-back; seedlings didn't harden off properly for winter and were vulnerable to frost damage. In southern climates it was fungal problems brought about by too much humidity.

The original tree tubes designs did work well in one part of the USA:  The Chesapeake Bay region.  When you think about it, that makes perfect sense.  The climate of the mid-Atlantic region is probably as similar to the climate in the UK as you can get in the USA, maritime and moderate (although it still gets both hotter and colder in the American mid-Atlantic). So while acceptance of tree tubes in the Chesapeake Bay watershed stayed strong, it lagged in other parts of the country.

The solution?  It seems so simple now it's almost laughable how long it took those of us "on the inside" to figure it out:  Air.  As in punching holes in the tree tubes.  As in ventilation.

Ventilated tree tubes provide several benefits:

1. Equalize the temperature inside and outside of the tree tube, which helps trees harden off properly for winter in colder climates.  Since the introduction of vented tree tubes, winter die-back has become a thing of the past.  I actually look forward to spring - no more do I have to field dozens of called from customers ranging from disappointed to irate about how their beautiful trees, especially black walnut trees, that had almost emerged from their tree tubes the previous year had since died back to just above the ground line.

2. Minimize build up of humidity, reducing the incidence of foliar fungi problems in the Southeastern USA.

3. Increase the level of carbon dioxide available to the tree inside the tube (it was learned that in solid un-vented tree tubes low carbon dioxide levels becomes a limiting factor in growth)

4. Allow some air movement through the tube and pin-points of sunlight, giving the tree "signals" that it is growing in an open field & causing it to allocate more of its growth energy to stem thickness and root development.  In other words: You get a healthier, more balanced tree.

Fast forward to 2010- well two days away from 2011.  Tree tubes have become all the rage for three reasons:

1. The problems they solve - deer browse, poor hardwood seedling survival, weed control, etc. - have only gotten worse since 1989
2. There is a much clearer understanding that while tree tubes are more expensive that planting trees and walking away, they greatly reduce the time & cost involved in successful tree planting
3. Tree tube design, especially the state of the art Tubex CombiTube Treeshelter, has come a long way and no provides outstanding performance across the full range of climatic extremes in North America

So now that you know why you're seeing tree tubes everywhere on the internet and in the field.  We hope you'll make Wilson Forestry Supply your source for the latest and greatest in treeshelter technology!

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