(CBS) — Get out the garden hose.

As crazy as that sounds, some tree experts say it’s necessary to protect trees during this unusually snow-free winter.

CBS 2’s Dana Kozlov reports.

Who’d even think about watering in the winter, right? Yet experts say the lack of snow — coming off of an extremely dry summer — is literally stressing trees out.

The water truck is out of storage at the Morton Arboretum and back in service –- yes, in January.

“In my 30 years of being in the Arboretum this has been one of the most unusual winters,” Kris Bachtel says.

Meaning, dry. Ten inches below normal precipitation levels. That’s a potentially big problem for trees.

Arborists say some trees already showing the effects of the drought by starting to brown. Winter watering — and mulching – while the ground is unfrozen can help save them.

“What you’re looking for is not to over-mulch. So we’re looking for 1 to 3 inches, and you don’t want the mulch to be built up around the base of the tree,” says arborist Alan Cartwright.

Without care — or water — both experts say the winter stress may show up mid-summer in the form of smaller or yellowing leaves, trees dying from the outside in and premature leaf-dropping.

But not all hope is lost. Snow or rain will help. But it has to be significant.

So how much water is required in the winter?

Bachtel says the equivalent of 1 full inch of rainfall every three weeks, especially on younger or newly planted trees and shrubs.