Also consider that if you are not building a hot compost pile, live weeds will probably continue to grow in your pile. Experts disagree as to whether the weeds' ability to reproduce is destroyed by the heat of the pile, but they all agree that hot piles are not uniformly hot. If you have any doubts about a weed, don't include it. It is not worth seeding your garden with weeds as you spread your finished compost, then finding out you were wrong. Send weeds to the municipal recycling site.
Invasive weeds grow by sending roots or runners out below or just above the ground.
Examples are Bermuda grass, bind weed, and white clover. Even shredding these types will not kill them. In fact, shredding them may just make them more plentiful, as they can reproduce from a small runner in adequate conditions. If you spread weeds invasive weeds out on concrete or other pavement that becomes very hot, they will dry up. When thoroughly dried, they may be added to the compost pile.