Thursday, September 26, 2013

New 'Micro-vented' tree tube hits the US market

A new tree tube with an intriguing combination of time-tested and innovative design features was recently introduced to the US market.

The Photosynth Tree Tube is in many ways a conventional tree tube, featuring a flared rim to prevent abrasion to the bark of emergent trees, twin-walled cylindrical construction for rigidity and durability, and releasable zip ties.

Venting has become standard for any high-performance tree tube.  Photosynth Tree Tubes have a 'micor-vented' design that has long been popular in Europe:

Rather than a relatively small number of larger vent holes punch sporadically in the walls of the tube, Photosynth Tree Tubes have thousands of small vent holes punched continuously from near the rim of the tube to approximately 16 inches from the ground.  This design result in more even gas exchange along the entire length of the tube.

The lower 16 inches of each Photosynth Tree Tube is solid for both herbicide spray and rodent protection.

Pricing of Photosynth Tree Tubes is highly competitive with other twin-walled tree tubes.  Tree tubes appear to be following - albeit at a slower pace - the pattern established with other new technologies, with the price decreasing as use of the technology becomes more widespread, competition among producers increases and production volumes increase.

It's a very exciting time in the tree tube industry.

Tuesday, September 3, 2013

Tree Tubes on American Chestnut Trees #2

This is the second in what will be an ongoing series of posts on the effectiveness of tree tubes on American chestnut trees.  To find the others, type chestnuts into the search bar.

A private landowner and American chestnut enthusiast in Mississippi purchased some 100% American chestnut seed last winter, and sowed the seeds in root pruning pots, grew them into 12 to 18 inch seedlings, and the planted them on his property.

While the seeds were getting started he researched tree tubes, knowing that upon planting his seedlings would immediately be subject to heavy deer pressure.  He contacted experts with the various chestnut restoration organizations for advice.  He was universally told that 4ft and 5ft tree tubes don't work well with American chestnuts.  The recommended method of establishment was either to use a 2ft tree tube (for rodent protection and initial moisture stress reduction) coupled with a wire cage for deer browse protection.

As we have discussed the basis of this recommendation was the poor results experienced by chestnut growers 15 to 20 years ago with the old, unvented, small diameter tree tubes sold at that time.  A 'corkscrew' or spiral growth habit of American chestnuts growing in tree tubes was a complaint back then, as was winter injury or die-back.

This gentlemen also discussed the issue with reputable sellers of today's vented tree tubes, and of course got a completely different story; he was told how the problems cited by chestnut experts harken back to earlier tree tube designs, and that results on chestnut with the vented tubes sold for the last 10 years have been excellent.

It was the typical conundrum for a private landowner and hobbyist:  Ask 10 foresters for advice and get 24 different - and often completely conflicting - answers.  Who to believe?  Luckily, this landowner did what so many other dedicated tree planters have done:  He didn't believe anyone, and put both methods to the test.

The upshot after nearly one full growing season:  "Tree tubes for American chestnuts should be 5 foot and trees should be above the tubes by August.  I really like the way the seem to help manage moisture."

Click the photo to enlarge.  The photo above is of his 'prize' American chestnut tree: Planted as an 18 inch seedling in spring 2013, photo taken Labor Day, 2013 with the tree now 2 feet beyond the top of a 5ft tree tube.

Asked about spiraling growth of American chestnuts in tree tubes he wrote, "The spiraling wasn't significant and now the trees have emerged straight as an arrow."

Here's another American chestnut tree emerging from a 5ft tree tube in the first season - note the very straight growth habit.  Click to enlarge to see the venting pattern on the tree tube.

The trees grown in 3ft tree tubes within wire cages also did well, but...

1) Aren't nearly as tall as those grown in 5ft tree tubes.

2) The wire cages for deer browse protection are an unnecessary added hassle and expense as compared to using the 5ft tree tubes which provide increased survival, faster height growth and deer browse protection.






Results like these show why a sea change among American chestnut enthusiasts. 

The "old" recommendation of using a 2 or 3ft tree tube along with a wire mesh enclosure for deer browse protection was based on a recognition of the effectiveness of tree tubes for rodent protection and increased seedling survival rates, but were also based on the negative results experienced when using the old unvented 4ft and 5ft tree tubes.

American chestnut planters using the newer vented tree tubes are seeing excellent results - and tree tubes are now fulfilling their promise as an indispensable tool in the monumental effort to restore the American chestnut to its rightful place in our Eastern hardwood forests.