Updated: Oct 8, 2020
Last April, I revisited this tree again, and you guessed it, pulled all the needles off. Except, this time, we took it one step further to really see how much this tree can take. Last year, we found that pulling all the needles off the tree didn’t kill the tree (Cool!) as long as we left the terminal bud intact, but still yielded long needles (about 2+ inches (5+ cm)).
Since we now know that the tree will survive a defoliation, we thought about different ways of stressing it further so that it would produce shorter needles. We came up with three options:
1. Pull off all the needles and repot the tree.
2. Pull off all the needles and wire the tree.
3. Pull off all the needles and cut off the terminal buds.
All three of these methods will definitely weaken the tree, but which one do we do? After much discussion, we decided to go with option 2 because it was the least stressful for the tree. Though wiring can be stressful for a tree, repotting and especially cutting off terminal buds can be much more stressful. Since we’re trying to find that tipping point between continued growth and die back, we decided to push the tree in small steps.
What Are We Looking For This Time?
Interestingly enough, as I was pulling off the needles, I noticed that the tree had many new back buds everywhere! As I wired the tree, I actually had to cut some of them away to reduce the crowding. Could I be on to something here??? My initial thoughts were that since the tree had no foliage, plenty of sunlight reached the interior and the tree responded by budding out (Isn’t that why we thin trees out?). I asked Mr. Tanaka his thoughts and he said it’s hard to say what caused the back budding. Since the tree has been de-candled every year, except for last year, the tree may have just reacted strangely and that the needle lost didn’t play a part at all. He then added that sone trees just back bud more easily then others. Of course, on the other hand, perhaps it is because so much sunlight is getting into the tree.
Nothing conclusive yet, but all very interesting…
Here are some things I’m going to be looking for as the tree continues to grow till the end of Fall.
1. Candle and Needle length
2. Changes in strength in the new terminal buds
3. Increased back budding
Currently, I checked on the tree and the terminal buds have started to push out new needles. Once October or November comes around, I will thoroughly go through the tree and post my findings with some pictures of course. I’m hoping by the end of the year, we’ll see shorter needles produced and the continuation of strong back budding.
The important thing about this experiment is not to see how good we can make this tree. Sure if things work out, that’s great, but what’s important is to recognize how the tree will react to certain stresses and give us a better understanding of Black Pines. Perhaps the different outcomes we see in this tree can lead to newer and better techniques. Maybe, maybe not… but at least we’re trying, which gives us at least some chance of learning something new as opposed to doing nothing, which means we learn nothing.
Thanks for following our little experiment. Lets see what the Fall brings!
Thanks for reading.