Dry Season Mystery Spots

Here’s a puzzle for you! Have a look at the satellite image above which was taken in December 2016. Notice all the white spots scattered across it?

Below is the same aerial view taken in the rainy season. Notice that the white spots are missing?

So what do you think the spots are? Scroll down after the jump for the answer!


The white spots are millet threshing grounds. In November, pearl millet is harvested and threshed to remove the individual grains from the heads. Often the millet is threshed on large, flat rocks which are quite abundant in our area due to the proximity of the Gambaga Escarpment.

Traditionally, men and women use long sticks to beat (thresh) the millet. In these modern times, I sometimes see hired tractors driving in circles over the harvest to crush the heads and release the grains.

After threshing, the chaff and millet stalks left behind cover such large areas and are in such contrast to their surroundings that they show up in satellite imagery!