How Do You Downsize A Large Pampas Grass

Question

Pampas grass is 25 years old, used initially to hide electrical boxes in yard, but have expanded to a large circle now, overtaking the yard and a porch railing.

Answer 1

You have a huge job ahead of you as Pampas grass puts down an extensive root system. Plus, the leaves are tough and razor-sharp. So be sure to wear gloves, long sleeves and long pants.

I would use a chain saw to cut it all back. Then if you have a strong shovel, start digging out sections all around till it is the size you want. If the clump was smaller, you could dig the whole clump and divide it with a saw. But if yours is 25 years old and taking over, I doubt you can dig the whole clump easily.
I also included instructions if you want to remove it entirely.

https://www.gardeningknowhow.com/ornamental/foliage/pampas-grass/pruning-pampas-grass.htm

https://www.gardeningknowhow.com/ornamental/foliage/pampas-grass/pampas-grass-removal.htm