Excavating on your property is not always something that requires the help of a professional; homeowners can often rent a bobcat or other heavy-duty digger and dig their own small pit for an in-ground wading pool or landscaping feature, or dig trenches for a large garden. However, there is some excavating work that should always be left to a professional; note when and why that is, so you know when to hire out this work rather than try to manage it on your own.
1. Farm roads
Excavating a farm road without proper barriers around it can allow moisture to drain away from the soil, toward the excavated area. In turn, this road can easily flood every time you water your crops, and this draining of the soil can make your property too dry to support vegetation. A professional excavator will ensure that farm roads are dug with proper walls on either side, holding back those potential floods and keeping the moisture in the soil where it's needed to support your crops.
If your excavation work involves any type of clearing, meaning more than just pulling up grass, shrubbery, and minor vegetation, this should also be left to a professional. Removing trees, even small landscaping trees, and large vegetation means pulling up their large roots from the soil. Those roots help to keep moisture in the soil and prevent erosion and runoff. Not compacting the soil properly can then allow for floods in the area of the excavation, while the rest of your property's soil gets very dry and dusty.
It's especially important to have a professional handle this work when it's being done close to your home or another building, as not properly filling in that excavated area can allow moisture to build up close to a building's foundation. In turn, this can cause cracks, leaks, and other such damage.
3. Building pads
Even if you need a pad for a lightweight building such as a shed or small barn, you don't want to do this excavation yourself. The soil needs to be compacted properly so that it is strong enough to hold the foundation or cement slab of this building, without sinking; this would cause cracks in the foundation or slab, and potential damage to the building itself. You also don't want the excavation to be too deep, as this can mean setting the concrete slab on moist soil under the topsoil, so that it absorbs that moisture and then cracks.