The USDA’s National Agricultural Statistics Service (NASS) conducts hundreds of surveys every year and prepares reports covering virtually every aspect of U.S. agriculture. Production and supplies of food and fiber, prices paid and received by farmers, farm labor and wages, farm finances, chemical use, and changes in the demographics of U.S. producers are only a few examples.
Many statistics are available for Wisconsin including some that are listed by county. The Taylor County UW-Extension office gets frequent inquiries about land rental prices. These are included in this NASS WI_County_Cash_Rent_09_2017 report (pdf). It includes both cropland and pasture. The most recent data is from 2016-2017. Please note that average prices are given and there can be a wide range of prices based on a variety of factors such as location, demand, availability, field condition, etc. Also the number of reporting operations in some counties may be small.