: a low usually several-stemmed woody plant
TheFreeDictionary by Farlex
A woody plant of relatively low height, having several stems arising from the base and lacking a single trunk; a bush.
What is the Difference Between Shrubs and Bushes?
As far as horticulture is concerned, there is no exact definition of when a plant is a shrub or a bush. A good general description of a shrub is a "woody plant with several perennial stems that may be erect or may lay close to the ground. It will usually have a height less than 13 feet and stems no more than about three inches in diameter."
I don't think that there is total agreement of what a tree is versus a bush.
If I were the owner, I would not want to have someone climbing that high. I would cut it down and pur something in that was of easily maintainable height.