After playing the Iroquois today I noticed that I was having a gather problem when I went to farms and plantations. After doing some timing tests with the farms and plantations I found a problem. All of the tests I did does not include any cards from the home city since those work fine. The technologies in the farms and plantations don't seem to work though. I got the same gather rates no matter if I got no technologies or all the technologies.
Gather rates for food came out to 30 food in 1 min. After researching all the technologies at the farm the gather rate was still 30 food in 1 min.
Gather rates for coin came out to 25 coin in 1 min. After researching all the technologies at the plantation the gather rate was still 25 coin in 1 min.
On a side note the large plantation, the Fazenda, from Brazil's civilization cause the villagers to gather at a slower rate as well compared to the plantation. The reason the villagers gather slower is because the villagers wonder around for longer periods of time on the Fazenda than on the plantation which slows the gather rate of coin from 53 to 23 coin in 1 min.