Presenting Data to Growers Dave Franzen NDSU Extension Soil Specialist, Fargo
Our Purpose- Conduct applied research relevant to grower needs and present results in an understandable manner. When a need for change is evident, present results in a transformational manner.
Presentation of data is strongest when strong data has been generated.
Nitrogen rate example- Mission is to see if N rate affects soybean yield-
Nitrogen rate example-
Mission is to see if N rate affects
Site locations must be low in residual N.
If sites are high in residual N, it would
be better not to conduct the study.
Weed control example-
Glyphosate control of lambsquarter.
Site should be screened a year ahead
for lambsquarter pressure. If
pressure is low, look for another site.
Number of sites should be related to impact of the study- Demonstration on spray drift effects- one or two sites probably enough. Review P recommendations for corn- need many sites over several years.
Make sure that all relevant background data is taken- If conducting an N trial and you have a low response to N even though residual N to 2 feet is low, taking soil samples to 4 feet to discover previously unseen deep N would be a good practice.
So, You have good data You have lots of good data You are really excited about this data How should you present it?
First- Remember the objectives of the study and relate the data to the objectives. Example- Objective- determine what effect different levels of field pea in beef cattle rations have on daily gain. Data should clearly emphasize these effects. Any other data should be minimized, or not presented.
% pea in ration Methane per animal Moos per day Water intake Feed intake per day Average Daily Gain Cost of feed None 25 120 20 8 11 $5.00 10 27 110 22 8.5 11.5 $5.40 20 28 105 23 8.7 11.8 $5.80 30 30 95 24 8.8 11.9 $6.20
The data you present should be relevant to your audience EPA? Water commission? Economic Analysis? Animal psychologist? % pea in ration Methane per animal Moos per day Water intake Feed intake per day Average Daily Gain Cost of feed None 25 100 20 8 11 $5.00 10 27 110 22 8.5 11.5 $5.40 20 28 105 19 8.7 11.8 $5.80 30 30 95 23 8.8 11.9 $6.20
Your killer slide to growers should be- % Pea In ration Average Daily Gain None 11.0 10 11.5 20 11.7 30 11.8
Treatment Plant N 5-leaf % 100 kernel weight Plants/m 2 Test weight Moisture at harvest Cob weight/20 plants Yield, Bu/acre Check 3.5 100 g 10 56 18 1.2 110 50 lb N 4.0 102 g 10.5 56.5 17 1.5 140 100 lb N 4.5 101 g 9.8 56.2 16 1.4 180
Most grower do not understand statistics (Figures lie, liars figure). They will not believe these differences are not real. Better to state-
There were no differences between the performance of products A, B and C on crop yield. The average yield for the treatments was about 90 bu/acre.
These differences are insignificant. What should we say?
Displaying the data in this manner makes it easier to make a non-significant difference point. Don’t fall into the trap of saying “there appears to be a trend’..
2009 Carrington, ave. 2 sites, post-anthesis application for protein enhancement. Schatz Faller yields over 100 bu/acre Slide courtesy of Greg Endres
Do not underestimate the power of the computer screen.
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Don’t be embarrassed about success. Celebrate it and challenge growers with it-
Spring wheat yields with N rate, Fortuna, 2009 N rate, lb/a Yield, bu/a 0 60 50 80 100 102 Be excited about the yields, not apologetic!!!! Challenge growers to do better!
Summary- -Do your homework and set up relevant experiments -Generate appropriate amounts of meaningful data -Display only the data the audience has the greatest interest in -Use charts and figures to illustrate trends if data are many -Use statistics as your bedrock and don’t disregard them when it’s inconvenient
Summary- -Challenge growers and don’t be apologetic if your yields are greater than theirs.