Going Deep: Apical Buds

  • Difficulty Rating: Beginner
Pruning Trees

Recently, I hired an ISA-certified arborist to come prune my bigger trees.

Despite knowing which branches I want to remove, sometimes I just can’t reach the perfect spot for making the right cuts. Certainly, I could hack away on the trees in an attempt to make them shorter or to lighten them up so they don’t drag on my rooftop or twist into my overhead utility lines. But, because I understand how plants grow and react to pruning cuts, I choose to bring in arborists from time-to-time to ensure the cuts are made in just the right spot to keep my trees beautiful and healthy.

Enter: Apical Tree Service.

When I asked Roger Brown of Apical how he came up with the name for the company, he laughed, “Yeah, people ask me what that means, and I tell them that only plant geeks really get it.” And, unfortunately, he’s right. The term “apical” isn’t something folks are usually bantering about at cocktails parties. That being said, it holds the key to much of what happens in plant growth.

 

Pruning tall trees

 

Think of it this way: the apical bud on a plant grows at the apex. Apical buds grow at the end of roots, the tip of branches, and at the top of trees. And it is these buds that that control much of what happens as the tree grows. Through chemical signals, they tell leaves where and how to form. They tell side buds, known as axillary buds, to hold tight or to open up and form into new plant parts.  When we remove apical buds in haphazard pruning attempts, all sorts of crazy growth can erupt on our plants.

Here’s my favorite analogy to help new gardeners understand what apical buds do.

Imagine this: An apical bud is the parent of an irresponsible teenager. If the parent takes off on vacation and leaves the kid alone with no oversight in place, they might come home to the hairy looking leftovers of a teenage party-gone-bad. Similarly, if an apical bud is randomly chopped off a branch and the rest of the branch is left as a stump on the tree, all sorts of crazy branches will begin shooting off that stump right away. It’ll be a hairy mess. Or, in the worst case: the tree will die.

 

Pruning tall trees

 

So, if you’re planning to do some pruning, be aware of those apical buds. If you need to remove a branch, be sure to remove the entire branch. That way you take out the bud at the branch’s apex (aka the apical bud), and you take out all of the axillary buds on the branch, which the branch’s apical bud had controlled. Sometimes this means you will need to make a series of cuts beginning at the apex and working your way back to the trunk. Taking out smaller bits will reduce the chance of hurting yourself, your surroundings or damaging the parts of the tree you wish to leave behind. As well, do your best not to damage the “collar” or “ridge” that forms at every juncture where a branch meets a trunk or another branch. And, of course, never try to cut the top off a tree to make it shorter. The end result will be an ugly, hairy mess of uncontrolled growth shooting everywhere. Or, worse yet, your tree will simply die.