| [College of ACES] | [University of Illinois] | [Illinois CES] |
The sample came from a large Norway Maple that had been cabled two or three years ago. The installation was done properly using half indh j lags. The lag was turned in so that the hook just kissed the bark. No bark scraping. A high wind came through the neighborhood and tore the tree apart. When i split the trunk apart I could see how the tree started to grow over the anchor. The new tissue that was forming under the open lag was not wounded. The tissue was comnpressed but I could not see any harm being done to the tree. After seeing this example I started to look for others. After studying several other samples I could see that the tree is not harmed by the open end of the lag. My conclusion is that if the tree is not harmed by a fixed point I don't believe it will by harmed by the Cobra system. The Cobra is not going to have as much pressure on the trunk as the j lags. We will probably find that the growth under the Cobra is a little less than above and below. This sma
ll amount of damage si m
uch easier to live with than the GUARANTEED damage by lags and bolts.
Another plus with Cobra is the simplicity of installation. On Friday one of the people in the class helped bring in my tools. Most of the tools go in a suitcase. There are so many tools that the original handle broke off and I replaced it with a piece of climbing rope. When he picked up the suitcase he grunted adn asked "What don't you have in here!". The only tool needed for Cobra is a pair of heavy duty scissors! Kind of a bummer because I do love to use power tools!
Tom Dunlap