Many people want to level-out surface irregularities in the lawn by rolling. Heavy rollers are not recommended for your lawn. Using rollers when the soil is wet or moist can severely compact the soil, particularly if you have fine textured silt or clay soil.

Soil compaction eliminates air spaces in the soil. Air is important for plant root growth. Hard, compacted soil prevents water and nutrients from moving into soil and hinders root development and growth of the grass plants.

If bumps and uneven areas develop, there are better solutions. To avoid these problems, follow these tips:

- Do not mow when it is wet enough for the mower to create ruts or depressions in the lawn.

- To level an area that is somewhat uneven, you can aerate with a core aerator and break up cores, distributing soil into depressions.

- Topdressing can be used in conjunction with aeration to fill depressions.

Using a lightweight roller may sometimes be helpful. Here are some guidelines:

- Use a lightweight roller to firm soil before or right after seeding to ensure good seed-soil contact.

- Roll sod lightly after you lay it to assure good sod-soil contact.

- During some years, the winter freeze-thaw cycles heave or uproot grass plants, and the lightweight rolling pushes plants down where they belong.

- You can also use lightweight rollers to level mole runs, night crawler castings, and ant hills, although these are usually flattened during mowing.

Roll, if necessary, when soils are moist but not wet. Most available rollers are the water ballast types. When you use them, don't fill them over one-quarter full of water. A good rule of thumb is to use a maximum of 200 pounds of weight