I have a problem with squirrels. they dig up my plants that are in pots and of course the plants sometimes get the root cut and they die. but your problem sounds a bit different.

If it was a sqirrel you would know because they scatter dirt all over the place as they dig.

Examine the root ball. Google for Root Knot Nematode. Compare pictures of what the infested roots look like to the ones from your garden.

Hi,

Think "voles". They burrow underground and gnaw on roots. Generally, they like tree and shrub roots, but they can be quite indiscriminate.

Over on the rose forums, some folks have claimed that they were able to lift a mature rose bush straight out of the ground because voles destroyed the root system. Although most people won't experience that level of damage, voles can take a toll.

Voles can make a complex series of underground tunnels. They can have multiple entry and exit points. There are different varieties of voles; some tunnel deeper than others. Pine voles tend to create deeper runs than other voles; because of that, they may not be obvious until the destruction becomes apparent.

The entry/exit holes are generally quite neat and level to the ground. Moles, which don't gnaw roots and don't graze on plants, have holes with dirt piled up around them. Not so with voles.

They are difficult to eradicate. They most reliable way to eliminate them is to use mouse traps by the holes ground. Some recommended baits are apple slices and/or peanut butter. Putting gravel or steel wool down the holes will not make them go away. Neither will predator urine, as most studies show that, eventually, most critters will figure out that there is no real danger.

Vole populations ebb and flow from year to year. Generally, there is a population explosion about every three years, then the population dwindles for a year or two.

Like most rodents, voles don't like to be exposed to possible predators. So, keep the grass and weeds around your garden mowed -- the lower the better.

To keep voles from breeching the garden area, some people use the 1/4 inch hardware cloth around their gardens/plants, putting part of it at least 6 inches underground...better protection at a foot underground.

Google "voles" - there is lots of information out there.