Deere is bringing more robots to the farm.

The maker of John Deere agricultural equipment said on Wednesday that it's acquiring robotics start-up Blue River Technology for $305 million. The deal is expected to close in September.

Based in Silicon Valley, Blue River makes "see-and-spray" robots that affix to tractors. They use computer vision to identify plants in the field in need of fertilizer, pesticides or other costly "inputs" used to manage crops. The robots are primarily used on lettuce, cotton and other specialty vegetables.

As farmers spend on more on inputs, they tend to spend less on heavy equipment. By helping farmers be more efficient in areas like fertilizing, Deere can free up more money for investing in tractors.

According to The Robot Report, 50 robotics and automation companies were acquired last year in deals totaling over $18.8 billion.

Blue River Technology raised about $31 million in venture funding from Pontifax Agtech, Data Collective, Innovation Endeavors, Khosla Ventures and others. The company claims that its "precision farming" technology can save farmers up to 90 percent of the volume of chemicals they use with more traditional approaches.

Phil Erlanger, a co-founder of Pontifax Agtech, told CNBC that the deal generated "attractive" returns for its investors but declined to give specific numbers.

With the world's population expected to reach 10 billion by 2050, "this necessitates more efficiency and innovation all along the agricultural supply chain," Erlanger said. He predicts that incumbents in the industry will increasingly snap up or partner with tech start-ups for innovation.