Tuesday, 23 August 2011

The Prairies: Part 2

It was the sight of running water that made this visit one of the most inspiring of my trip.

I was visiting Phil Jerde, his wife Jill and their nine children on their ranch in North Dakota and was being driven round the western block of their land. Now, one of the benefits of managing grassland to increase soil organic matter is that the water cycle improves. As Jay Fuhrer so abley demonstrated with his infiltration test, soil with high organic matter has great structure and absorbs water like a sponge. Conversely water struggles to penetrate low organic matter soils and so runoff and evaporation losses are much, much higher.

Phil and family have been managing their grasslands properly for a number of years now, grazing with a mixture of buffalo and cattle and giving adequate rest periods to the forage plants between grazings. Slowly, soil organic matter has been increasing. Rains are beginning to soak into the soil, being held in-situ rather than running off down hill. This water slowly seeps through the soil strata, being available to the plants for longer and gently weeping into draws (the natural valleys in the landscape).

Slowly, these draws are starting to green up. It begins with a small clump or two of warm-season (ie C4) grasses, often big bluestem or native switchgrass. Each year these clumps get larger until they start to meet and gradually the whole draw, or valley, becomes a verdent green oasis within the parched landscape.

It doesn't stop at this, though. The grasses gradually extend up the hill, as the soils improve, the water table rises and the bottom of the draw becomes damp, even in the middle of the day in 90 degree heat in August.

The ultimate sign that things are working properly is when you find, as we did, flowing water in the bottom of the draw. Getting the water flowing through the soil properly is vital whether you're in a low or high rainfall area. I am still agog at the incredible improvements Phil and his family have made to the landscape, just by managing the grazing properly.

The greening of the land. As the water cycle improves, soil becomes more water-retentive. This, coupled with an adequate rest period allows native warm-season grasses to establish once again. The line between green and brownish vegetation can clearly be seen on the side of the draw and higher on the hilltops

Big Bluestem grass in a draw on the Jerde ranch. There's a huge amount of forage here compared to the drier, shin-high material further up the hillside. What is exciting is the way the green area slowly spreads up the hill each year. I believe that one day, if Phil and his family carry on managing the land so well, the whole of his ground will be covered in dark green, tall, valuable forage.

Water lying in a draw, high up in the prairies in 90+ degree Farenheit heat

1 comment:

  1. Excellent writeup, Tom. So great to have you here, though the time was too short. Hope the rest of your travels are filled with more great experiences and safety. Be blessed!!! Jill Jerde