Sunday, 3 April 2011

Follow the Dirt

This may sound like a post on the election but it's not. I'm talking real dirt, the stuff you can grow things in.

Keeping soil on fields where it can do so much good, rather than in ditches or waterways where it can do so much harm, is something that's dogged agriculture, road building, construction, etc. forever. In some ways the problem is very simple: soil that's uncovered and loose mixes easily with water, and travels with that water wherever it goes. Water runs downhill (that darn gravity at work), so in a province like PEI with so many sloping fields that run into streams, rivers, and estuaries, that's where the soil ends up. Bare fields are also vulnerable to wind erosion. Many Islanders remember three years ago when there was no snow cover, freezing temperatures, and  bare soil became liked freeze-dried coffee, and blew around for miles in every direction.

It's a problem everywhere. In Canada a senate investigation headed by Herbert Sparrow  released Soil at Risk in 1984:

"The Committee's major purpose in this report is to take the reader on the
equivalent of an airplane ride over Canada to make clear what soil degradation is and
how serious it is in all regions of the country. By increasing the awareness of this
situation the Committee hopes to help make soil conservation a national issue. Our soils
are at risk. Our future is eroding. It is time for action."
Hon. H.O. Sparrow, Chairman

It takes between 300 to 500 years to produce an inch of soil, but it can be lost very quickly. At it's worst

10 tons of soil per acre can be lost. It's the fine particles and organic matter that get lost first. Both are essential to productivity. Even in strict dollar terms,  hundreds of dollars of nutrients leach from fields, and end up in waterways fertilizing sea lettuce and other algae which cause the anoxic rivers we see during the summer. None of this is good.

Here's the solution:

What's called fall cover crops  protect soils with vigorous root systems and plant growth. Some farmers spread straw which can be very beneficial. Many long for the day when all fields have some kind of protection going into the winter.

What keeps it from happening? Time is one issue.  If a crop isn't harvested until the mid to end of October, then many farmers feel there just isn't enough warmth and sunlight to germinate a cover crop properly.  Unfortunately two of PEI's most important cash crops are harvested late. Soybeans often don't come off until early November. There is an effort to develop new, earlier varieties that will remove some of the risk of a wet cold harvest which can substantially cut into the quality of soybeans, and give farmers a chance to plant a cover crop.

The other crop has a more interesting story. In the 1870's a talented American plant breeder called Luther Burbank selected a potato variety that became the most popular and economically important variety in North America, the Russet Burbank. It's that long brick like potato that's good at everything from french fries, to baked potatoes, to mashed.  The hitch? It needs a 130 days or more to properly mature, that's why the potato diggers and harvesters are so busy through October and even into November, that's why so many potato fields lay bare through the winter.

Potato breeding is trying to come up with varieties that mature earlier, but retain the same outstanding characteristics.  That hasn't happened yet.

Consumers do play a part in this. The french fry companies argue that the fast food giants demand french fries that are long enough to fall over in the box, and it's the russet burbank's size and shape that produces fries that do that.  Just to be mischievous, I did a story one day asking fast food buyers if they would still buy french fries if they were a little stubbier. Almost all said sure. If the fast food players could be convinced of this, and pass that information back to the french fry makers, then farmers could look at growing smaller potatoes with shorter growing seasons, and more fields could be covered in the winter.  Probably too much to hope for, but it wouldn't hurt if you're ever asked to fill out a questionnaire by a fast food company to say smaller fries are OK with me.  You might save shellfish in your favorite estuary.

I did take some pictures in my travels last week (end of March 2011) that I wish farmers would consider. I call it the last row test. There is a lot of fall ploughing on PEI (a topic for another day), and where a farmer decides the edges of the field is can say a lot. The first field has a nice covered headland that will keep soil from moving into the ditich, while the other one is ploughed right up to the ditch, and won't. I think whenever a farmer pulls back from the edge of a field, he or she sends a strong message to the neighbours that he/she cares about keeping the soil where it should be. When it's right up to the ditch, he or she is sending a very different message.

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