Exponential growth happens when the rate of growth of something is proportional to the amount of the something that you have. Doubling every day is an example of exponential growth.
Plants, until they approach their natural limits, tend to exhibit exponential growth: the more leaves it has, the faster it can make new leaves. My Wisteria has been growing exponentially for a few years now, and it was time to prune it. Drastically.
Wisteria sends out creepers to explore growth opportunities, and these can get everywhere, and when they get there, they get thicker as they age. So if they get into the roof, they can prise off the tiles, or if behind a drainpipe, they can prise it off the wall. My plant was under the tiles and behind the drainpipe. Time to act.
Wisteria is a stringy plant, so if your pruning shears are not sharp or there is the slightest gap between the shearing blades, when you try to cut the branches, you will end up with two bits of wood joined together by a tough stringy bit that is hard to break. The first thing I had to do was get a new set of shears.
It was a three-day job, yielding three trailer-loads of clippings to take to the dump. Some of the creepers were amazing - one that got under the tiles must have been 6 yards long when I pulled it out, and must have grown entirely parasitically - it can't have got any light where it was.