The light spots on the map are most probably places where teff - local cereal is being threshed. (Teff/Eragrostis tef, also known as dwarf millet, is to Ethiopia what maize is to Mexico and rice is to China: the country's most important foodstuf.)
- zoomed view on this place https://satellites.pro/Ethiopia_map#9.6 ... .714099,18
Teff threshed by using animals walking on the harvest

By Ji-Elle - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.p ... d=31146097
The harvest season traditionally lasts from the beginning of October to the end of January, depending on the region, rainfall, altitude, and other local features. The average growing season of teff is 17 weeks.
Teff dries for an average of 40 days between harvesting and threshing. Traditionally, farmers prepare the threshing area by coating it with a layer of cattle dung. Once the teff has been brought to the area, the teff is threshed by oxen trampling the teff. Further separation of seeds and cleaning is done by hand with traditional tools.

(source: Teff farming in Ethiopia: a literature review. Background brief/2021. Full text PDF https://4det8y3z1n391t76me8rfynx-wpengi ... ief-vf.pdf)
short VIDEO
1/ Ethiopian Manual Teff Harvest with Sickles and Bullocks (traditional) https://youtu.be/e7HgtReLlvo
2/ modern harvest https://youtu.be/6syTkQXE7P4