1

Myths and Facts -Tree Protectors, Grow Tubes and Shelters

Not knowing the truth about tree protectors and shelters can cost you. PLENTY.

MYTH: The Greenhouse Effect is responsible for faster growth and better health.
FACT: The Greenhouse Effect is over-rated.
Although there is some truth to the belief that the Greenhouse Effect is responsible for the trees' accelerated growth, research shows that more of the accelerated growth is due to the lack of wind and the effects of phototropism. As wind speed increases above seven mph, the tree's defense mechanism begins to shut down photosynthesis to prevent the tree from drying out. Without photosynthesis, the tree stops growing.
Some manufacturers attempt to close off their protectors and shelters in order to create a "mini-greenhouse" micro-climate. This "closed system" approach seldom achieves the intended result and could actually be fatal to the tree. These manufacturers tout the benefits of this "closed system" at the same time they warn growers to lift the shelters when the weather is unseasonably warm. That's because the so-called greenhouse prevents the dissipation of heat and moisture. However, raising the shelter can create a "chimney effect" that can cause the leaves to become dessicated.
A certain amount of heat and moisture is good but too much of a good thing is a bad thing.
For photosynthesis to take place at a healthy rate, leaves must absorb huge amounts of carbon dioxide from the air. Restricting air flow into the protector reduces inflow of carbon dioxide, and that's simply not good for the trees.  
Closed system shelters slow dormancy in the fall and accelerates emergence from dormancy in the spring. While other trees around them are keeping pace with the change in temperature, trees inside closed system shelters are not.
In the fall, the problem occurs when the temperature drops below 28 degrees Fahrenheit and remains there for several hours. By then the trees not "protected" by these shelters have usually gone dormant and are therefore not adversely affected by the drop in temperature. Not so for the trees inside closed system shelters. They freeze and often die. For that reason closed system shelters must be lifted each fall, even though that's difficult because the shelters may be stuck in the ground.
Then, after these trees have gone dormant, their shelters must be lowered to the ground to provide protection from winter weather. The procedure must be repeated again in the spring; otherwise, the trees in closed system shelters will emerge from dormancy too soon.
If that's not enough hassle, during the summer, when temperatures soar into the 90s for days on end, the trees will bake and sometimes die, if the shelters aren't lifted.

OVERCOMING THE GREENHOUSE EFFECT
Venting or opening the shelter/protector is the only way to use the good the Greenhouse Effect does and avoid the bad. Both Max Grow style tree shelters are available with vent holes in their sidewalls. The slit tube style can also be easily opened up to allow for even greater air circulation.

 
MYTH: Size doesn't matter.
FACT: Some tree species will not thrive in shelters with small diameters.
Reports from the field have confirmed that protectors/shelters that are 3 1/2 inches in diameter or less will cause the leaves of most trees to bunch up about half to two-thirds of the way up.
The more leaves the tree produces, the more congested it gets. Eventually, the tree stops producing leaves, the leaves that are there begin to rot, and the tree stops growing or produces a deformed trunk.
Many growers do not become aware of this problem until it is too late because they rarely have time to check what's going on inside the shelter. From the outside, the tree may look okay. However, what's inside may be deformed or have suffered dieback.
Both Max Grow slit tube design remedies for this problem. With the slit tube design you can easily expand the diameter by attaching a second or third protector, using the lockties. This make Max Grow slit tube flexible enough to be used to protect tomato plants, strawberry plants and ornamental bushes.
Max Grow closed designed tube is furnished as a nested set of five, each with a slightly large diameter, ranging from just over 3 1/2 inches to 4 3/4 inches. 

 
MYTH: You never have to remove shelters.
FACT: Shelters must be removed when their job is done.
There is a widely held belief among some tree planters that because tree protectors are designed to photodegrade over time they can be left on the trees indefinitely. For several reasons this belief is incorrect.
 
The photodegradation of polyethylene and polypropylene takes place at a rate inversely proportional to the amount of UV retardants added to the pre-extruded compound. Most manufacturers add enough UV to preserve the protector for about five years on a worst-case basis. That means that most protectors are going to last at least five years in the most difficult climates. However, because climates vary so much from one hardiness zone to the next and from one season to the next, protectors can easily last up to ten years.
Regardless of how long the protector lasts, when its job is done, it will not simply disappear. It will either remain on the tree, sometimes damaging the tree or it will fall to the ground. Sometimes, they break into pieces and after a few years can cause quite a litter problem.
Part of the reason we plant trees in the first place is to improve the environment.  Thousands of pieces of plastic litter do not improve the environment. What's more, littered landscapes will attract the attention of people accutely sensitive to environmental well-being.
The other problem is that some protectors will not break apart and will strangle or girdle the tree. Tube-type shelters are notorious for causing this problem. They therefore must be removed.
 
One manufacturer has recently modified their shelter by including a weakened seam, called a laser line, running from the top to the bottom. It's unknown at this time exactly what effect this will have on the tree in the long term. Our tests of this shelter showed that although the laser line broke easily enough (perhaps too easily) the top and bottom rims of the shelter remained intact, which could potentially strangle the tree. But even if the laser line worked and the shelter dropped from the tree, the fact is, it's still lying there or, having broken into small pieces, sailing about in the wind.
So, please do what we do: Clean up, pick up, recycle. Remove protectors when their job is complete. 

3180 West 250 North
West Lafayette, IN 47906
800 875 8071  756 463 1011