The US agricultural sector―especially farms producing labor-intensive crops such as fruits, vegetables, and horticultural products―relies on unauthorized immigrants to perform many seasonal and routine tasks US citizens will generally not do.
Reducing the availability of immigrants for agricultural work will increase labor costs and eventually lead to new technological innovations that improve farm labor efficiency and even technologies that can mechanically harvest delicate fruits and vegetables.
However, in the short term, higher production costs for fresh fruits, vegetables, and other commodities will lead to reduced domestic production, higher levels of imports, less selection for consumers, and higher food prices.
Further, a shift to innovative mechanization of fruit, vegetable, and horticultural production is likely to increase farm size in those sectors since larger farms can benefit from new economies of size and scale.