The phrase 'most productive lands' is correct and usable in written English.
You can use it to describe an area that produces an abundant or plentiful amount of crops, minerals or other resources. For example, "The farms across the river are some of the most productive lands in the state."
For example, one can imagine a situation where farmers convert most productive lands to crop production in response to a higher demand for ethanol.
Private ranch lands are often the most productive lands in the West, too.
Soil erosion significantly affects the most productive lands in Argentina, particularly the region called "Pampa Ondulada".
The large landscapes contain significant amounts of private lands that are often the most productive lands and offer some of the best potential for biodiversity conservation and other conservation objectives.
Because fertile ground provides more of a cushion for the bomb upon impact, the trigger fuse is less likely to detonate on these lands, making the most productive lands the most dangerous to farm.
At this aggregation level, the model uses the most productive lands first in response to the need for cropland expansion in each region.
It includes some of the most productive land of the delta, supporting a dense rural population.
The former independent African mountain kingdom quickly lost much of its most productive land and its political autonomy.
The CAP funnels money into the highly mechanised farms on the most productive land such as the Paris Basin and East Anglia.
If, as in Africa, the most productive land is taken over by cash crops for sale to rich countries, then the life-blood of ordinary people dries up.
Tractor makers hope to install computers that can digest this information, then automatically concentrate the application of costly fertilizer and chemicals on the most productive land.
