By Nathan Mueller

In the digital data age of production agriculture, producers and companies are utilizing new tools to answer the same questions — just at different scales. These questions include: How can I best manage products for a region? How can I optimize production across a farm or by field? How can I manage variability within a field down to the row?

Over the past two decades, many producers, agronomists and companies have collected robust data sets to help answer these questions. This data includes yield data, 2.5-acre grid soil sample data, high-density soil electrical conductivity (EC), pH and organic matter (OM) data, normalized difference vegetation index (NDVI) or normalized difference red edge (NDRE) imagery, and more.

Growers have collected as-applied data from variable-rate fertilizer applications, variable-rate seeding and multi-hybrid plantings. Companies are increasingly interested in gathering this information in cooperation with producers to help generate future recommendations to best manage the farm, field and areas within a field.

What about making old information new again?

Even with all this data and spatial data analysis tools, questions still remain about some areas within a field when it comes to unexpected performance. In some cases, I have found that farming practices from over 80 years ago can explain some of these questions that I couldn’t answer using data from the past 20 years. There are two resources to tap into and digitize: an older generation and historic aerial photos.

For a farm family has owned the same land for generations, they may already have great insight into historic farming practices from parents and grandparents. But more often, producers rent land from owners who are one or more generation removed from the farm, and that generational knowledge about field history has been lost. Either way, historic aerial photos can revive old memories or create new ones.

One of the tutorials I put together for our University of Nebraska-Lincoln precision ag data management workshops demonstrated how to utilize old aerial photos from the 1930s to 1970s to explain current spatial patterns in crop performance. People can get old aerial photos from several sources and georeference these photos using precision ag software.

For example, part of one field in eastern Nebraska was pasture until at least 1959 (see image below). An 80-acre field had been farmed north and south, but some east-west patterns showed up in certain years like 2012. Some 1940s aerial photos showed it used to be farmed east-west as several smaller fields.

3 LAYERS: Three data layers being used within precision ag software include a georeferenced aerial photo from 1959, a current satellite image and a recent corn yield map. A portion of the field was in pasture as of 1959 (north portion). The current yield map (green is higher yields) still reflects this past land management.

For Nebraska, one source of old aerial photos is through U.S. Geological Survey's Earth Explorer. Another option is to work with staff from the University of Nebraska-Lincoln School of Natural Resources to access the hard-copy archives of old aerial photos dating back to the 1930s for some areas within Nebraska.

A specific area of interest (legal description for the farms of interest) needs to be provided, but the current cost of pulling photos from the archive and digitizing those aerial photos is only $14 per photo.

People can choose to visit the archives and find the aerial photos of interest. A person’s labor then reduces the cost per digital aerial photo to $5. Once old aerial photos are digitized, it can be georeferenced using precision ag software. To learn more about this process, contact the UNL Nebraska Maps and More Store at 402-472-3471.

Take an opportunity this winter to try this for a farm that is rented or recently purchased, and see if an old aerial photo can be made new again to help solve the Rubik’s Cube of Precision Ag.

Mueller is a Nebraska Extension cropping systems educator for Dodge and Washington counties.