Orchard is planted on 20 acre tract , coarse soils sand no gophers removed for at least 20 years prior there were lots ,started trapping township pays one dollar bounty here so saved feet paid property taxes that first year with gopher bounty , Have been at it 15 years now and have used a gopher machine last few years but still trap every year some move in spring and fall , not many mounds any more , have to be diligent see a new digging get a trap in it . They will take out young trees older larger root mass will tolerate some damage , gophers don't seem to impact lager trees as much , but I dislike em so much have no tolerance for any in the trees . we trap it all adjoining land , frontage ditches , its a daily battle more so spring and fall as that's when they disperse from established near by colonies .