Satellite images show another record wheat harvest on cards

Debra Matabvu

ZIMBABWE is on course for yet another record-breaking wheat harvest this year, with over 60 000 hectares (ha) of the crop, nearly half the total hectarage planted this year, having already matured, according to preliminary data obtained from the Zimbabwe National Geospatial and Space Agency (ZINGSA).

Satellite images captured by Zimbabwe’s space satellite — ZimSat-1 — indicate that, while a “significant portion” of the winter wheat crop is still developing, current data is pointing towards a bumper harvest.

A record 121 982 hectares were planted this season, with production expected to surpass 600 000 tonnes (t), exceeding the country’s annual wheat requirement of 360 000t.

Using the multi-temporal satellite images collection technique to harvest data between May and July, experts at ZINGSA were able to accurately project winter crop production in some parts of the country.

The complex and highly technical data collection technique involves acquiring satellite images of the same area at different times.

The images can be acquired using a single satellite or multiple satellites.

They can be acquired at different times of the day, different seasons or even different years.

Analysis of the data collected so far shows that nearly half of the total crop planted this season was in good health and has reached maturity stage.

“It should be noted that these are preliminary estimates based on the same crop but at different phenological stages such as vegetative development and tillering as a result of differences in planting dates,” reads the report.

“Thus, these estimates are based on the wheat detected using remotely sensed images up to the month of July.

“It is anticipated that final results will be generated in the month of August.

“The results of the initial winter wheat estimates show that a total of 59 291,96 hectares was observed to be under wheat.”

The mapping exercise identified multiple wheat fields, reflecting the effectiveness of remote sensing and classification techniques used by ZINGSA, according to the report.

“However, a significant portion of the wheat crop could not be observed through satellite imagery based on the July image as a result of late planting in some areas,” it continues.

“The dataset includes fields planted in mid-June, which may not have fully matured by the time of analysis.

“This factor may affect the accuracy of the wheat detection, as the phenological stage of the crop can influence the vegetation indices and their interpretation.

“With time, we anticipate an increase in winter wheat area as more wheat will be detected from satellite imagery.

“The final, refined results are anticipated to be published by mid-August 2024.”

According to the Ministry of Lands, Agriculture, Fisheries, Water and Rural Development’s latest report on wheat production, Mashonaland West has the highest hectarage under the crop, at 34 876ha, while Mashonaland Central has 29 574ha.

In Mashonaland East, 21 987ha were put under wheat, while farmers in Manicaland planted 13 482ha.

In Midlands 12 459ha are under wheat, while Masvingo (3 501ha), Matabeleland South (4 190ha), Matabeleland North (1 913ha), Harare (32,7ha) and Bulawayo (6,82ha) account for the rest of the production.

The report also shows that harvesting of crops planted between April and May 10 is expected to commence towards the end of next month, while wheat planted between May 11 and 30 will be harvested around mid-October.

Wheat planted after May is expected to be harvested towards the end of October.

The Government has set a target of increasing wheat production to achieve self-sufficiency, in line with the National Development Strategy 1.