Pete Van Dyck is the owner of Van Dyck Earthworks & Design LLC. He’s a land designer, jobsite manager, and heavy equipment operator. He specializes in regenerative land design and installation for farmers, ranchers, homesteaders and conservationist private land owners.
His mission is to rehydrate Texas by using biological rich soils. Instead of a large percentage of rainfall ending up as run off, he wants to store every drop of rain that falls on the soils.
Droughts are part of Texas. A recent, memorable drought was the great drought of the 1950s.
Texas seems to have cycles of floods and droughts – a boom and bust cycle.
We have a drought, then flash flood, and then even more drought.
The average rainfall in the Texas Hill Country is 30 inches.
When we have a drought, we want the soil to absorb most of the rain when it does come, but the soil doesn't because there’s nothing to stop it and it flows away down to the local creek or river. So when it does flood, the soil doesn’t keep much of the water. The soil is also washed away and valuable top soil is lost.
We need to store the overflow rainfall in the hills rather then let it flow down to the creeks. With the water in the rocks of the hills, springs will form and water will seep out. That’s the way to keep rivers flowing.
We have enough rainfall, it’s just not being utilized properly.
Soil fertility
Healthy top soil has a high level of organic carbon in it. If there is one percent organic matter in the soil, then the soil can hold 27,000 gallons of water per acre. One inch of rainfall per acre is 27,000 gallons.
So if you have three percent organic material, you could store up to 81,000 gallons of water per acre. Three inches of rainfall at one time is considered a deluge. Image if the soil could store it all.
Hill Country soil is about 1-3 percent good top soil. But that’s not everywhere in the Hill Country. In a lot of places, it’s just caliche and rainfall flows right over the rock.
Top soil is created when soil is in contact with plant roots, so the soil is literally created by the plants.
During good times, plants produce more sugar (food) than they need. Consider this excess food as liquid carbon. This liquid carbon is fed on by microorganisms that live in the soil and generate more good soil. The final digestion of this liquid carbon by fungi creates humus in the soil. Humus is not broken down by bacteria, so it stays in the soil and can be used by the soil to hold more water and as a place for plants to spread their roots.
Land owners can improve the soil’s capacity to hold water simply by having as many green plants as possible growing. Don’t keep bare land bare, plant it.
Texas has lost a lot of top soil by losing soil fertility.
Pesticides, herbicides, chemical fertilizer, tillage, and overgrazing all contribute to destroying soil fertility. Tillage destroys ground cover. If you’re going to till, after you've tilled plant something that will grow.
Stopping top soil loss
First start on the hill sides and build terraces such as a limestone ledge. Make a burm on the downhill side. What’s a burm? It’s a narrow ledge or shelf along the top or bottom of a slope. Call them terraces. Cover that base soil in the terrace with mulch. When it rains, the water will be held and run-off will be reduced. Grass will grow in the burm.
You can also place a pile rocks in potential water flowing areas so the rocks slow the water down.
Throw seeds behind the piles of rock and it will grow as it rains and soil collects.
You know you have bad erosion when the water flow from the rainfall cuts a gully along your hill. Basically build a dam (more or less) with rocks. That will catch soil that flows with the rainfall and the soil builds up.
Another option is to place logs on the ground. That will slow water from going downhill too fast, also. Again, soil will build up behind the logs.
As soil builds up in either scenario, plant a cover crop. For instance, try broadcasting rye seed in the winter. What you want is photosynthesis year around. So keep planting seeds year around.
Erosion starts as soon as a raindrop hits the ground. What you want is for the raindrops to hit a plant or other ground cover. That helps stop erosion.
Bottom lands
Don’t plow. He suggested using a no till seed drill to plant. It’s a $16,000 device for your tractor that drills seeds into the ground. The device opens the soil, drops the seed into the hole, and pushes the soil back over the seed.
Use a keyline plow (or Yeoman’s plow). It has thin shanks and goes into the soil without disturbing the top soil very much. Advantage: it gets the plants in deeper. And deeper is where the plants can find more water. It is designed to lift and aerate the soil while limiting soil disturbance to minimize oxidation of organic matter.
If you have a field, put a cover crop on it in the winter if you use the field for farming in the summer. For instance in the winter plant native grass. Wildflowers are cool, but the deer eat them up. Rye grass is best. The deer don’t seem to eat rye grass that much.
Grazing management
He recommended Jaime Elizondo Braun of Regengraze and his techniques. You can find information about it on Pete Van Dyck’s website, www.DroughtProofTX.com, but the bottom line is to keep your cows concentrated in small plots. That way they eat all the grass, plants that are there, not just the desirable ones. He also says the cattle will drop a lot of manure, and guess what, you have organic fertilizer. So when the cattle are done, put them in another plot and don’t put them back in that plot until the plants/grasses have recovered from grazing.
Dung beetles are your friends. They put dung into the ground and that is fertilizer. Problem: if you worm your cattle, the poison you use may kill the dung beetles.
Sources:
Terra Purezza Farm: www.terrapurezza.com. They deal with regenerative agriculture.
EarthRepairCorps.org: is a group he works with. They are promoters of good permaculture design.
And of course, his site: www.DroughtProofTX.com.
Final note:
The 70 percent of the rain from the Memorial Day Flood in Blanco a few years ago ended up as run-off.
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