Pages

RPM Soils, LLC

Friday, December 29, 2017

Year End Photos

This is the Dicamba year, so we will start off with that. 
Dicamba Damaged Beans

Pineapple Weed was a new one on me

Sometimes you don't know why the rain gauge seems off

Scenic Barn Near Mt. Olive

Pella Iowa Balloon Races

Tulip Time in Pella Iowa

Short Corn didn't seem to affect yield 

Saturday, December 16, 2017

Soil Surveys and Precision Agriculture

Winter meeting have begun and we have been busy with them.  Two weeks ago at the 2nd annual AgData Conference in Iowa City we heard two presentations about the shortcomings using soil surveys to define management zones for precision agriculture.  Tom McGraw, consulting soil scientist brought up the issue in his presentation on the Flaw of averages.  Afterward, I had a discussion with him about the topic.  His comment was that the USDA Soil Survey is the best in the world, but it is not good enough in many cases, to make site specific management decisions.  The Veris tool is a popular way to define management zones based on Electrical conductivity and soil color.  I have seen the Veris work very well and I have seen it not work well. 

Shannon Gomes, like me an old USDA soil scientist made a similar presentation later on.  Gomes is using lots of deep soil borings and an EM meter to define ones.  Gomes says that rather than try to use all the standard soil features to define ones, we can narrow it down to a few such as topsoil texture, color and depth, subsoil texture and dept, available water holding capacity,  and cation exchange capacity.  His methodology sounded kind of expensive, but considering that the work should last, until further refinement is necessary, perhaps it is not too bad.  Gomes did mention that he is looking over all at the five factors of soil formation.  They are:

  1. Parent Material
  2. Biota (including native vegetation)
  3. Topography
  4. Climate
  5. Time
We try to refine the soil survey in by using GPS to define the boundaries between soils that have similar management considerations based on the five factors of soil formation.  We sometimes end up with rather large ones that contain similar soils,  The large zones are broken down further to end up with 10 acre or smaller zones.  Our process is not expensive, but require us to be o n the ground, and it requires a trained eye.  The photograph below shows zone boundaries as I have defined them in Pike County.  The purple lines are the Soil Survey lines.  You can see that we are gaining signifigant refinement with a relatively simple process. 

Pike County Soil Survey vs GPS defined zones. 

Monday, December 4, 2017

Randy Dowdy Program

Last week were invited to attend a presentation b champion corn grower Randy Dowdy.  Linco-Precision was a co-sponsor and invited us to the program.  dowdy may have made on of the best farmer presentations I have heard.  He had 4 main points.   He uses drainage to remove excess water. He uses irrigation when water is short.  He does a lot of soil testing and tissue testing in order to fine tune his fertility program.  He likes to spread his risks by spreading out his planting dates in a 3 to 4 week period. He pushes his soil fertility to the maximum.  He advocates for 1 pound of nitrogen for every bushel of corn. 

I listened and tried to figure a program that would work in Illinois.  Despite having decent annual rainfall amounts, we really do not have a good source of irrigation water except in the major river bottoms.  I am an advocate for drainage.  We can drain our fields economically.  His discussion about tissue sampling is leading me to consider offering a revised program that includes tissue sampling.

I was surprised that he is not pushing high populations although he is using narrow and twin row spacings to maximize sunlight to the plant. 

Dowdy was thought provoking and interesting,  While I am not sure how to implement his program entirely, I think we can learn some things from him.  If you get a chance to hear him speak, go for it.