Answer: As long as the grass clippings are short - half an inch, or so - you can leave the clippings on your lawn rather than bagging. They will decompose and while they are decomposing they will release nitrogen, which is helpful to your lawn. I would bag clippings that are excessively long, such as you might find in the spring when the grass is vigorously growing. The long clippings take quite a while to decompose and can while they are sitting on top of the turf they can block sunshine which can slow the growth of your grass. Each time you mow your mower will suck up the decomposing clippings and redistribute them while it is chopping them up into smaller and smaller pieces. Bagging shouldn't be necessary.
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