Final answer:
Before 1960, home lawns in the northern U.S. were mostly composed of native grass species that could survive with minimal water, reflecting the limited irrigation and reliance on dry-farming practices at the time.
Step-by-step explanation:
Prior to 1960, the species that comprised most home lawns in the northern part of the U.S. were often native grass species suited to the local climate and soil conditions. Due to a lack of irrigation systems and the need for dry-farming techniques, grasses that could survive with minimal water were chosen. Subsequently, with advancements in water availability, different types of grasses could be cultivated, leading to the diversity of lawn species we see today in various regions.