But you also have to beware of what caused the vegatation to die. If you use weed killer on your lawn, the grass clippings can be hazardous to put on your garden. It stands to reason. You must also be aware of the acidity or alkalinity of what you are adding and you will potentially want to amend the mix.
I have a compost pile that consists of fruit and vegetable scraps, coffee grinds (and filters), and egg shells. The coffee grinds will increase acidity, and if I also put a lot of pine needles in the same mix it will further increase. Depending on the plants I am working with, I will want to back off the acid, or just not use the organic mix on those plants. Too much of a good thing…you know what they say.