Paulownia.

Thank you! I've read enough to learn it is invasive, so out comes the chain saw after all. This plant seems to have sprouted from under the brick 'half-wall'. It is new growth because my house is 50 yrs old. I certainly don't want it to continue growing in it's location. Much appreciation to floral_uk.

That is in a bad spot. They are invasive by self sowing and it probably seeded itself in a crack there. You may need to give the stump a little drink of poison or it will come back.

They can be fun to grow purposely for the huge leaves.. To get the big leaves you have to cut it to the ground every year. They don't bloom and make seed when you do that.