Rear Roller Mower

Scalping
This is a confusing term as it refers both to bald patches appearing on the lawn and to a professional trick that lawnsmen use. The bad form of scalping can happen:

• If the mower is used on soft ground where the wheels sink in and lower the cut to below the minimum height
• On turns, if they are taken too fast and the inner edge of the turn is cut too low
• When ruts form from not varying direction of cut
• If the height of cut is set too low.

However, there are times when it can be advantageous to mow your lawn to lower than the optimum growing height. This form of scalping is used by professional groundsmen to break winter dormancy in the grass because it helps the soil to warm up more quickly and can eliminate winter weeds or stop their seed production for the following year.

Tearing
This is where clumps of grass are lifted from the lawn or where individual grass blades are torn rather than being cleanly cut. This happens because:

• Cutting surfaces are not sharp enough
• Or when the cylinder and bottom blade of cylinder mowers are incorrectly set causing the cylinder either to bump the ground or the bottom cylinder blade to be too close to the roots of the grass to cut cleanly.

Ribbing
Is an uneven pattern to the cut seen as a series of ragged stripes across the length of a cut, rather than a stripe produced by turning the mower at the end of each row. It happens when:

• Cylinder mowers are operated too fast, reducing the number of cuts, this is also called the 'teenage haircut' because it's the kind of grass cutting often seen when teenagers are given this chore to complete before they go out!
• The grass is too long even for the highest cut and a second cut is necessary
• The cylinder incorrectly set on a cylinder mower.

A scalped lawn can need expert treatment to help it recover. Scalped lawn photograph courtesy of elvissa