|1880 US Agricultural Schedule|
First, let's define the agricultural schedule in case you've never had the chance to use it.
Agricultural schedules of 1850, 1860, and 1870 provide the following information for each farm: name of owner or manager, number of improved and unimproved acres, and the cash value of the farm, farming machinery, livestock, animals slaughtered during the past year, and "homemade manufactures." The schedules also indicate the number of horses, mules, "milch cows," working oxen, other cattle, sheep, and swine owned by the farmer. The amount of oats, rice, tobacco, cotton, wool, peas and beans, Irish potatoes, sweet potatoes, barley, buckwheat, orchard products, wine, butter, cheese, hay, clover seed, other grass seeds, hops, hemp, flax, flaxseed, silk cocoons, maple sugar, cane sugar, molasses, and beeswax and honey produced during the preceding year is also noted. The 1880 schedules provide additional details, such as the amount of acreage used for each kind of crop, the number of poultry, and the number of eggs produced.*
These non-population schedules of the US federal census include the farm owner's name, what the farm produces, as well as the size of the farm and its value. So it's a great schedule to learn more about an ancestor's specific farm but it provides very little in the form of details about the farmer. A search to see how many women are represented as farmers in these enumerations is made impossible because of the lack of a gender category. But women are represented in the agricultural schedule.
If you have a widow whose husband was a farmer, check the agriculture schedule. That's where I found my farm widow in 1880 after her husband was murdered. Thea agriculture schedule documents that she was growing Indian corn and cotton on her farm of 44 acres in Austin County, Texas. She also kept a small number of pigs and chickens. Her modest farm most likely helped her feed and house her children, ages 17 years to 6 months. Interestingly enough, she is not listed with an occupation in the corresponding population schedule (her 17 year old son is listed as a farmer) but the agricultural schedule lists her as the farmer.**
Add to your to-do list searching the agricultural schedules of the US census. Whether you specifically look for a female ancestor or peruse the enumerations for your ancestral family, the agricultural schedules can provide you with rich details about their life. Even if she's not the farmer listed, you'll get a better sense of what her duties may have been as the farmer's wife.
Ancestry.com - Nonpopulation Schedules 1850-1880
National Archives - Nonpopulation Schedule
Agricultural Schedules 1850-1900
2012 Census of Agriculture Highlights - Women Farmers
**In the case of Jane Chatham, my ancestor, she was enumerated in the population schedule on the 23/24 of June and in the agricultural schedule on the 7th of June, 1880.