"When the ice skating is poor the voles will have parties" - very loosely translated from a Norwegian saying.

In fall, there comes a time when the air temperatures become colder than the ground temperatures. This is technically called the "autumnal thermal overturn" (descriptive enough). At that time, the plants really start to die off and animals look for shelter underground. The longer the period of cold without snow, the more plant tops, and the animals that feed on those plants, die. With the lack of vegetation, small rodents like voles are more obvious to their numerous predators thus, more are eaten. At the same time, with cold temperatures and little or no snow, the ice skating gets better and better. Good for skating, bad for voles.

Inversely, if the soil is warm, the plants are green and the weather is mild when the snow flies then the rodents hit the jackpot! The warm insulating snow protects them and their food supply from the ravages of winter and they are well hidden from their predators. The warm soil "rots" the snow at ground level making it easy to tunnel through and, for voles especially, life is good. Fall 2003 the weather was beautiful until the end of October (the last day in fact) when it dumped on the trick-or-treaters and the rest of the landscape. The skating on local lakes, ponds and streams was sadly absent that winter; the voles had parties.

Snow, with its loose flaky structure, is an excellent insulator. In really cold climates, the temperature above the snow may be as much as 50°colder than in the subnivean environment (below the snow).

Other notes of interest about the subnivean environment: Coyotes, martins, weasels and snowy owls can hear prey through the snow and are able to catch a few.

As a consolation, in years when the snow melts rapidly, water flow under the snow can flood the rodents' tunnels and the soil surface just as new litters are increasing the populations. A big die-off can result. In some winters moisture and cold extremes can create ice lenses that trap and suffocate the rodents.

The insulation that snow provides is good for many marginally hardy plants and it helps protect dormant animals like frogs, toads and queen bumblebees and yellow jackets from deadly freeze thaw cycles. These animals may also be eaten by the rodents in winter or drowned in a wet spring thaw.

Biosol organic fertilizer, for whatever reason, still seemes to repel voles from many lawns. There was definitely more damage in 03-04 than in any past winter we recall, but there appeared to be less damage where Biosol was applied as confirmed by many, many gardeners. In spite of the work of rodents, lawns that have Biosol applied in the fall come out much greener and healthier and repair more quickly than those without it. We use Biosol in the nursery and when landscaping as part of our own planting fertilizer blend (Biosol, Dr. Earth Vegetable & Fox Farm's American Pride). Because many more people have asked for it, we carry some Biosol in summer as well as the tons of it, in the fall (it is still the absolute best fall fertilizer we've found).

The rabbits have become a major complaint among gardeners. They ate branches and bark on top of the snow. We had quite a few in the nursery this winter. Let us know what bothered your garden this winter.

Lets hope for some good ice-skating in November and December.