Crop history to evaluate field history and variability
The Crop History is very important to evaluate field history and variability. Data in the crop history includes, for each past season, the following items:
- Extraordinary events such as hail, frost, drought, flood, etc.
- The crop in each field, including the sowing date and harvest date
You may use this Crop history template spreadsheet to send your crop history. If you have similar information in a different spreadsheet or format, you may also send that.
|Note:||"Similar information" being summarized field data. Please, avoid sending detailed sowing operations data; we may need further inquire to make it clear, which may result in a delay for your product delivery|
Knowing Crop history is directly influential in the quality of produced data and the subsequent decision making; it helps in choosing images from dates with more significant information. For instance:
Dry and wet years
Crop history is important to be aware of any period with extreme weather conditions in the area, and subsequently for choosing the images which will be used in this service in general, and the productivity maps in particular.
This is an example of extreme rain conditions from 2001-2009
This image from 2001 (435 wavelength combination) shows how extremely wet it was; flooded low areas are shown in green.
An image from the same area, from 2009, shows extreme drought. No sector with surface humidity can be detected.
Knowing your sowing date
Helps in making a more precise choice of dates for your images, considering the different stages and evolution of your crops.
This is an example of images on the central field in the image, during the months of January-February-March 2009.
The central field is shown in cyan, with a an incipient vegetation growth which contrasts with the well grown crops, shown in fuchsia (soybean) and burgundy (corn).
This is an NDVI for this field:
The central field shows a pinky hue, which becomes more intense in the southern area.
Crop growth (soybeans) begins to cover the whole field.
The crop keeps growing
The last image shows little to no difference within the field, and it's only when using NDVIs that differences between plant stages within the field can be detected. Here's the NDVI: