I have created a bunny heaven. I cannot take the passive approach and hope that they will feast elsewhere. Physical barriers of every sort and description are the only way to save some greens for human consumption. The added problems of groundhogs and voles make the physical barrier system somewhat more complex. Voles burrow underground so the fencing has to be buried, at least to 6 inches.
Voles are also very small so the fencing has to have gaps no bigger than fine chicken wire.
Groundhogs are not hindered at all by this type of fencing and appear to be able to dig beneath anything. What's even worse about the groundhogs is that they destroy everything in their path on their way to the choice vegetable of the day. Battles such as this are rarely won but always interesting. Trying new ways to keep out the wildlife is almost as interesting as trying new varieties of plants. I have conceded the growing of many favourite bunny foods but have insisted on continuing my attempt to grow the perfect beet.