Well.. over the course of one month not a single grass tile has spread to an adjacent tile. Let me explain my situation: I have an 11x14 animal pen enclosed by an iron fence that holds about 8 horses, a bull and four champion deers, that used to be fully covered by grass. Once a grass tile turned into a packed dirt tile, it would usually become a grass tile again after several days. Nothing to worry about, since the grass would spread faster than the animals would pack it. Since I wanted to catch up with the farming and beverages skill a bit, I planted strawberrys and repeated this cycle five/six times. After that I got tired of farming again and planted some steppe in a cross-pattern (like planting all the black or white tiles on a checkerboard) to recover the dirt into grass once again. After 4-5 days, I noticed that not a single grass tile had spread: the ones that neighboured the grass outside the pen (which had an iron fence inbetween). IF a single grass tile would have spread, I would have noticed by either a new packed dirt tile or a new grass tile, which didn't appear in these 5-6 days. So that's when I submitted my first /support call. Nothing much came out of that one: I should wait some more and plant some more grass, since this was not a known bug. And since I didn't have that many animals in the pen, grass still should spread faster than being packed. To keep the animals fed, I planted some flowers now inside the pen instead of steppe (about 1/3rd of the whole pen in a rectangular shape), since I wasn't sure whether steppe did spread or not; and the community gave varying answers. After another 10-14 days, none of the grass tiles inside the pen had spread, neither the one adjacent to the iron fences. Most of the steppe was packed by now, so I kept cultivating those during the 5 days to keep room for new grass. That's when I made a second support call. Apparently the CA didn't fully understand the situation so it took some time to explain. Again, this was not a known bug and couldn't appear locally, since, everyone would suffer from it or no one at all. So I was suggested to post this in the forum. After some discussing, I had an Eureka moment. All the grass I planted inside the pen had flowers on them. Maybe that the flowers would prevent grass from being spread. So I ripped these flowers out of the grass and used them to plant even more grass tiles in rectangular shapes. And still, after a week or two, none of the grass tiles had spread in(to) the pen. My animals are fat but starving now Side notes: YES, I am aware that grass does not spread on packed dirt, or at least, not as fast as on normal dirt tiles. And yes, I cultivated all the packed dirt to prevent this! I have a second farm (6x6) with 8 horses that has the same issue. Not a single grass tile had spread over the course of a month, without replanting anything, but with cultivating after the second week.