Gully erosion is one of the most serious problems a farm owner can face. It’s a form of land degradation that can affect the farm infrastructure, paddock management and even prevent you from accessing parts of your property.
There are ways of repairing it but you should focus the bulk of your efforts on prevent rather than repair. That’s less expensive and it will allow you to use your property, productively as it can be used, as long as you can even when the conditions aren’t as you liked them to be.
It’s essential that you treat your gully when you notice that it has a problem with erosion and to do it before the problem becomes sever or too complicated to deal with. There’s a lot that can happen due to erosion and none of it is good for the farm.
-It’s dangerous for cattle, machinery and for the people living on the farm
-You’ll end up losing water that you may use productively
-Erosion moves the top soil downstream leaving you with less nutritious land
-The erosion will only get worse over time if it’s not treated
Gullies happen when surface water concentrates in a flow line with inadequate groundcover. This results in scouring of soil until a deeper channel is formed. Once they are started they can expand and grow both downslope and upslope.
Severe problems with gullies mostly come from heavy rainfall rom storms and cyclones. This means that with the changing climate erosion may become more of a problem for farmers even in areas where there was no problem before. The timing of these storms can help you prepare.
There are a few steps you’ll need to take in order to stabilize a gully when you notice that there’s a problem with erosion on it. For the most part, there are five steps you should take.
-Star with diverting surface water from the gully. This is done by using well-engineered surface water earthworks.
-Next, stabilize the eroding gully head
-Shape the walls of the gully
-Fence the gully off
-Encourage the grow of grass and other vegetation on your gully since that’s the protective layer that will keep the water from eroding the land more.
The water that’s moving into the gully is what’s causing the problem and it should be diverted and reduced right away. The diverting should start up steam and you should focus on using surface water management options. This includes spreader banks immediately above the gully head. Spread banks may be needed on both sides to prevented the water entering the area.
The options for doing so include: spreader banks, grade banks, grassed waterways and shallow relief drains. This is what you’ll need to prevent the erosion from getting worse and then you can start repairing it.
The following step should be to stabilize the gully head. Not all gullies erode beyond that and that’s where you should start once there’s no more water coming to it. An actively eroding gully head will need a drop structure, which can be a concrete flume, or built from sandbags or gabions (rock-filled cages).
This is best done by shaping the walls of the gully
-Do not leave rip lines or loose soil if the soil is dispersive.
-Use gypsum treatment on suitable clays.
-Add deeper topsoil to the exposed dispersive subsoil if possible.
-Seed with a suitable annual to get rapid groundcover as early in the season as possible.
The most important step however, is the last one. Creating a vegetation ground cover will help you prevent eroding from happening ever again and it’s a way to protect the soil from other problems as well. It will take time to establish it but when you do it will keep your property much safer.
It’s sometimes worth placing fences alongside your property to protect the first layer of vegetation if you also have animals on the farms because you’ll need to plan your grazing practices to cultivate the groundcover and to feed your animals.
Gully erosion is something that can really damage your property and your profits. You’ll need to protect it and to reverse the damage made by the water as soon as you can. This is partly done in the long run by having a groundcover of plants growing at all times.
When the problem arises your first goal should be to shape the walls of the gully and thus limit the area that will be damaged by the water. Stabilizing the gully head which is done with sandbags or concrete.