Some lawns might look perfectly smooth at first glance, but when you walk or drive your lawnmower over them you feel the bumps. This can be due to several different reasons.
Older lawns tend to develop bumps, lumps, and ruts over the years. This is especially an issue if you have mature trees that aren’t contained by a landscaping feature. As the roots start to spread and grow they sometimes force the soil around them up and out of their way. Worse still, some mature trees might even have exposed roots that can protrude enough to possibly damage your lawnmower’s cutting blades or cutting deck.
A lawn with trees is also more likely to have errant sticks hiding deep down in the grass. Sometimes even your best efforts to pick up the lawn will miss a stick, which can damage a lawnmower blade or the pneumatic lawnmower tire.
The underlying soil can also cause lumps and bumps to bubble up in your turf over time. Especially if the soil is rocky mixed with water-absorbing clay. In a scenario like this, the clay can absorb water in the late summer into fall.
Then when it freezes in winter the natural swelling of the freeze-thaw effect can put pressure on the surrounding soil. This can gradually force rocks toward the surface. Even if the rock never emerges, they can press up on the underside of the turf and the thick matt of grassroots.
Past digging can also affect how the soil in that area settles over time. When soil is disturbed and backfilled the are often looks level but settles into a rut with rainfall and foot traffic. Even years later you might see a deformation in the turf that is difficult for a lawnmower to pass over smoothly.
Can A Bumpy Lawn Damage My Lawn Mower?
A lawn with lumps and bumps can damage your lawnmower in a couple of different ways. Right off the bat if your mower blades hit an emergent rock, the rock can be ejected out the side or back at dangerous speeds. A rock can also damage the cutting deck, the shaft of the mower blades, or ding the mower blade itself.
In a severe case, there have been times when the mower blade was badly damaged or shattered by hitting a large rock. This is even more likely to occur with electric mowers that tend to have relatively thin cutting blades.
Can Scalping Damage My Lawn Mower?
The term “Scalping” refers to times when the lawnmower’s cutting blades make contact with the surface of the lawn or something else like an emergent tree root. When this happens the damage to the turf or the root can be significant.
Of course, lawnmower blades are meant to keep moving at a very high speed. When they contact a physical object it can dull the blades, bend the driveshaft, and potentially fracture the cutting blade itself.
How Can I Prevent Scalping?
The easiest way to prevent scalping is to set your lawnmower’s cutting deck higher. Of course, this isn’t always a reasonable solution. Constantly leaving your lawn 2 or 3 inches high might not look that good to the neighbors. Not to mention constantly long grass tends to invite unwanted rodents and insects.
There are some lawnmower, particularly riding lawnmowers that have guide wheels integrated into the cutting deck. When you go over a rough patch the wheels automatically adjust the cutting deck like a set of shocks, to prevent the blades striking the turf.
Do Large Lawn Mower Wheels Help With Rough Terrain?
Let’s say you’re not all that worried about scalping and you are vigilant about picking up sticks or rocks that appear on your lawn. Yet, you still need to deal with turf that is naturally lumping and bumpy. There are a few things you can look for in a lawnmower to help with ride comfort.
In the case of a riding lawnmower, things like independent suspension, and enhanced suspension on the seats will help reduce the jarring motion of driving over rough terrain. You might want to also think about getting a riding lawnmower with four pneumatic tires, rather than two rear tires and two front casters.
In general larger wheels will help the mower move more smoothly over rough terrain. Pneumatic wheels filled to the correct pressure will also help cushion the ride.
Our Picks For Rough Terrain Riding Lawn Mowers
In the case of a push mower or a walk-behind lawnmower, large rear wheels are also very helpful. Especially if you are thinking about investing in a self-propelled lawnmower. The larger diameter of the wheel tends to give the lawnmower more purchase on the turf. In some cases, it also helps make the most out of the torque produced by the self-propulsion system.
Our Picks For Rough Terrain Push & Walk-Behind Lawn Mowers
Can I Still Use A Lawn Mower With A Damaged Cutting Blade?
Let’s say your best efforts to clear away rocks, sticks, and avoid big bumps still wasn’t enough to prevent your lawnmower’s cutting blade from taking a beating. If you do happen to hit something significant, you should still stop, let things cool down and then check the blade.
If it’s dinged on a cutting edge, you might be able to get by just fine with mowing the rest of the lawn. Afterward, you should strongly consider having the blade professionally sharpened, or replaced.
If your inspection reveals a crack in the blade, a bend, or a broken-off piece of the blade, then you absolutely need to replace it before you try cutting with the lawnmower again. Once a blade is badly compromised it throws off the overall balance of the entire cutting system. Not only can it badly damage the lawnmower, but it could also cause severe injury to you.