Scared? I (We) Should Be

I have been asked to speak next week at a meeting sponsored by Stratford Farm Equipment.  They are promoting the successful Trioliet feed mixers to their customers and have asked me to be part of the program.
I am not a gifted public speaker.  While attending school I would avoid it at all cost, but after a couple of spectacular crash and burns I have learned that I can overcome the fear of sounding like an idiot.  A sense of humour is a good defense.
The best thing about preparing a presentation is that it forces you to research your topic, even when it is a topic that you know very well.  You still learn new things that either help to support or cause you to change your point of view. 
One of the things I am addressing next week is fertility and soil testing, which can be really boring unless you have a strong message. 
I came across some interesting data presented by two friends of mine, Allan McCallum and Paul Sullivan, at the Southwest Ag Conference in Ridgetown. 
A concern among all practising agronomists is the decline in soil test levels for phosphorous and potash.  We see it regularly and agree the trend is alarming.  The following graphs help explain why.

This is a graph of phosphorous usage in Ontario.  You can see fertilizer application peaked around 1980.  High interest rates, low commodity prices and agronomists advising to reduce phosphorus rates all caused the usage to decline sharply.  The vertical bars indicate the amount of phosphorous that is removed by the crops we grow.  Today we are taking more phosphorous out of the soil than we are putting back. 

This is the potash graph.  A little complicated, but the trend is the same as phosphorous.  More being trucked out of the field than coming back.

A different way to look at it is to compare the nutrient removal by crops over the last 25 years.  We are taking a lot more nutrients out of every acre with our high yielding crops than we were in the 80's.  The following chart indicates the amount of nutrients removed by a 3 year crop rotation of corn, soybeans and wheat.  If you want to see the numbers for rotations that include corn silage and haylage, come to the meeting next week. 

Our fertility programs today need to be tailored to reflect this change.  Unfortunately, this is not happening.  I know fertilizer is expensive, it hurts to write the cheque.  But the extra dollars needed to keep up are not huge and if you drain the fertility bank, you lose the farm.  We have been blessed to be able to live on the fertility reserves that our fathers and older brothers handed down.  What are you going to hand down? 

And the next time your buddy complains about the price of fertilizer, instead of agreeing with him, ask him how much he is willing to pay for land rent.