on contour swales & berms on flat flat land
Does anyone have advice on creating a series of on contour swales and berms on flat poorly draining clay soil. I am envisioning alternating widely spaced bands of wetland and raised beds. Half the property (total size 13 acres) is woodland with hundreds of fallen emerald ash borer killed trees, perfect hugel culture fodder to be incorporated in the berms. The other half is old field (ploughed 50 years ago) covered in wild bushes. A 100x100 ft pond 8 ft deep is centered at the north end of the field. The old field is where I'd like to do the swaling and berming because there is sun and a water source. The land tilts ever so slightly - high point to the northwest and low point to the southeast. The woodland is to the north. On the south end is a narrow lovely marshland created by a berm to the south that prevents drainage into the municipal ditch. They keep cleaning out the ditch and building up the berm. I love that marsh. How deep should the swales be and how wide? Deep and narrow or shallow and wide? How high and wide the berms? Any advice? How about advice on guilds to plant? Woodland trees are 80 - 100 year black and white oaks, shag bark hickories, maples, ash are all dead, some elms, some linden, some poplar. Field is mostly assorted dogwood bushes, roses, wild grapes, eastern red cedar, hawthorn, ash stump sprouts, with young oaks starting. Any thoughts are welcome.