Thanks Thistle but I'm no expert, my knowledge comes from trial and error, mostly error. If I make a mistake mum's the word

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As to cutting clematis back, if it's got a good root system you could cut it back now but if it's one that blooms on old wood like the ones in Group 2 you would be sacrificing next years blooms, our doberman got in a snit one year and ripped one of my mature group 2 clemies off at ground level right around this time of year, I thought it was a goner but it came back in the spring better than ever but it took a couple of years before we saw any blooms.
If it blooms on new wood like the ones in Group 3 it can be cut down fall or spring as they bloom on new wood, I usually do these in the spring.
As a rule the Group 1 clemies need little pruning unless getting to be a tangled mess or need to be contained, I have cut these to the ground on occasion, takes a year or two to recover, they bloom on old wood. The Montanas are rampant growers, here's a picture of a cutting of Montana wisonii I gave my neighbor. He planted it on his shed, it jumped the fence and climbed through our yellow cedar tree, when in bloom it has many scratching their heads as this cedar is by our back fence, the other side of the fence, a 4 lane highway

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If you don't know which group your clemie is in I would follow Thistle's suggestion and protect it. If you know the variety you can look up to see which group it's in and then decide how you want to prune it in the future.
Annette