EFFECTS OF FIRE ON SOIL HEALTH

     Fire has always been controversial.  In the past I have used it, and may, in a rare circumstance use it again.   With the equipment we have available to us now, fire is an outdated, archaic practice.
     It has been obvious to me for many years that fire was destructive to soil health.  Denuding a field by any means, negatively impacts soil.  Fire not only removes the litter that, at some point in time will become part of the organic component of the soil, but it also burns some of the SOM already present.  The soil, losing its cover, is exposed to the natural elements and become warmer in the summer and colder in the winter.  Bare soil effects natural processes, some associated with temperature extremes, that impact moisture available to the soil as well as moisture in the soil.  This in turn effects the soil biota, that effects nutrient cycling, which has an effect on raising crops.  This is not linear as the statement may insinuate, but is a complex interrelationship of many elements.  We are slowing gaining the understanding that processes resulting from less tillage, and more cover is basic to improving soil health.



   
   

TILLAGE vs NO TILLAGE

      We have recently taken on some land with conventional fallow to seed this fall.  We have not dealt with conventional fallow for 25 years, and are no longer equipped for that condition.  This field has well over a 100 year history of tillage.  In our area, do to the geological history, that includes the Great Missoula Floods, most fields have several soil types.  [ Missoula Floods is a 3:50 minute animated video showing some history of our Palouse Hill landscape. ]  By the time fall seeding takes place, a cultivated field has had several tillage operations, and it's usual to have areas that powder and flow down slope in front of an implement.  It's hard to hold seed at the desired depth in that situation.  The pic shows a raindrop impacting bare soil.  When rain falls, soils on cultivated fields tend to seal up due to poor structure left by impacting raindrops and tillage.  With these conditions, the most successful tillage systems I have observed, are those that reduce the number of tillage passes to reduce aggravating powder development, and for the last pass prior to seeding, use a spiral packer to firm up the ground for the drill opener gauge wheel.
      A decision had to be made on how to get this cultivated fallow field seeded.  Rather then take the time to round up equipment to prepare this field for conventional seeding practice, Kye decided to take his chances with our heavy no-till CrossSlot drill, follow it with a tine harrow, and hope for the best, --expecting to do some reseeding later.  Conditions allowed the crop to emerge and reseeding was unnecessary.  Sometimes it's better to be lucky than good.
       Some fields, or areas within fields, may require 3-5 years of no tillage to stop the seal over effect of the soil left from years of intense cultivation.  We hope with our no-till experience, we can shorten that time frame without giving our landlord a hemorrhage.
      When we started no-tilling there were problems that needed to be worked out.  In our early no-till years there was no path for success developed through many years of experience, as there was with the conventional tillage system.  That is behind us now, and transition can be shortened by years.
      Now, --what do I see as significant between the two systems (tillage - no tillage) that exist side by side sharing a 3/4 mile long border, in our Palouse Hills region.  We have had only a few months to deal with the cultivated ground but a few things have stood out.
      ---The no-till fallow ground is firm with good armor and operations create little or no dust.  There was no dust coming off the field during windy conditions.
      ---The tilled fallow ground has deep (2-4") soft dirt with no armor and it was very dusty from any operation performed.  The exposed surface did produce dust from wind when it blew before the surface sealed.
      ---This mild winter, allowed us to walk all over our no-tilled field without sinking.  With care, I seldom got mud up the side of my boots.  That was not the case with the tilled/winter wheat field.  Walking in that field always left your boots a mess and you left deep tracks where you walked.
      ---The no-till fallow/winter wheat ground did not seal the surface when rainfall occurs.
      ---The tilled fallow/winter wheat ground sealed over immediately from light rainfall.  Fortunately most of the winter wheat had emerged by the time measurable rain events arrived, and what wasn't emerged, was very shallow and able to push through the thin weak crust that formed on the soil surface.
      ---In early February, when scouting the fields, as I walked down our steep (20-40% slopes), there was no noticeable increased squishiness in the no-till fields.  Our no-till fields have a very high infiltration rate and no tillage pan to restrict water movement through the upper profile.  There was noticeable squishiness as I progressed down the slope in the conventional fallow/winter wheat field.  This condition is when water moves slowly under the surface, on or near the restricting tillage transition zone from high to low elevations.  Surface erosion was expected, but did not show in the conventional tilled field.
      There is much that I could say to support no-tilling over tillage; however, this post is to utilize the rare opportunity to compare side by side effects between no tillage and tillage as we experienced them.

Climate & Water Vapor

     Throughout this past year there has been numerous reports of rainfall in excessive amounts in many different locations throughout the US.  It seems like reports have come in from everywhere except the Inland Northwest, --us.   In October there were reports of flooding along the Snoqualmie river in western Washington.  Now it is no surprise to hear that the Snoqualmie floods.  That's an annual spring event when the snow pack starts melting off the western slopes of the Cascade Mts, --but in October!!!(???), that's most unusual.  Last fall I read where there were 10's of thousands acres of farmland flooded along the Missouri River this past year and that currently there are thirty thousand acres of farmland still under water and expected to stay underwater until April when the 2020 flood season normally starts.  In recent years I have been watching/listening to reports of heavy rainfalls throughout the US.  They use to be associated with thunder storms on the Great Plains and the areas around the southeast and the gulf hit with the occasional hurricane.  Not any more.  Heavy rainfall events are now being reported west of the Rockies with southern California receiving heavy rainfall events as well as along the Oregon coast and now maybe the Washington coast. West of the Cascade Mts., particularly Seattle (the Emerald City) is noted for it's rainy weather, and of coarse, the Olympic Rainforest is a historical feature of Washington, so rain is not a new phenomenon; however, the amounts and in the time received may be changing.  I can't even imagine the damage to our farmland should we start receiving rains that measure in the inches per hour.  These thoughts  play a part for the passion I have to armor our fields and increase moisture infiltration.  How long will it be before we have to endure one of these high volume rain events?  There was a time that I thought our location between the Rocky and Cascade mountains would shield us from any devastating weather event, but, I'm not so sure any more.
      Atmospheric rivers (of water) seem to be more prevalent around the globe.  We mostly hear about what is going on in the US, but other places are getting similar weather events.  In one of her presentations, Dr. Christine Jones, makes reference to the excessive atmospheric moisture, and questions why more attention is not given to that greenhouse pollutant.  I did a quick google search of atmospheric pollutants and found that neither CO2 or moisture was listed as a pollutant.  There are caveats, to these and other elements, depending on the authors specific mindset.  The media gives us the impression that the debate is over, but what I see in the weeds, is that the debate is anything but over.  There is a lot more than CO2 involved with our climate and we don't understand what that is.