Leaves and other plant tissues are in abundance in the fall. This is the time of year when nature replenishes the soil. These materials will break down over the winter to make fertilizer for spring growth. I suggest leaving the leaves to reduce your fertilizer application next season.
The amount of nutrients varies in tree leaves and other organic materials. On average, tree leaves are 0.6% nitrogen, 0.1% phosphate and 0.6% potassium. Grass clippings are 1.2% nitrogen, 0.3% phosphate and 2% potassium. These materials are fertilizer sources. They can be used in the landscape and not bagged and carted off.
Big leaves take a long time to decompose. I run over them with the mower to chop them up. A thick layer of leaves on the lawn will prevent sunlight from reaching the grass. These leaves need to be chopped up or moved to the vegetable garden or flower bed where nothing is growing that requires light.
Streets that have leaves along the curb are a source of fertilizer. If these leaves stay there, the fertilizer is wasted and sent down stream where it can be a pollutant. These leaves can be chopped up and put on the lawn, garden or compost pile.
If you have trouble incorporating all of the material at once in the garden, allow the materials to stand for one to two weeks and repeat the tilling process. This allows organic materials that have been covered to begin to decompose.
Materials remaining near the soil surface can be incorporated more easily during the second tilling. After tilling, moisten the soil if natural rainfall is not sufficient to encourage complete and rapid decomposition of organic materials. Take care not to till or cultivate soil if it is excessively wet. This can create clods that make it difficult to break up and prepare a fine seed bed for later planting.
Work with nature at this time of the year. That means adding nutrient to the soil in the way of leaves and other organic materials. Your plants and the environment will benefit.