Which of the following inventors of the 1870s had a directing major impact on the prairie ecosystem

The steel plow and barbed wire

Explanation:

It was in 1837 when John Deere, a blacksmith from Illinois invented a steel mouldboard plough that was strong enough to cut through the stubborn roots of the prairie grasses. This invention turned millions of acres of prairie land into fields for arable crops and grazing ground for huge herds of domesticated cattle. The starving Indians who were displaced resorted to slaughtering the bison in 1872 to 1874 that resulted in the decrease of its population from 7.5M animals to about 750 only.

the dark variety, as they are not visible on the dark tree barks

explanation:

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