Wednesday, October 20, 2010

Leave the leaves

It's that time of year where the neighborhood is busy raking and blowing leaves to get them off their lawn.

My City had a great article in their latest newsletter encouraging residents to utilize 'nature's mulch' rather than putting it to the curb.

In our yard, we let the leaves lie where they land (other than on walkways where they're put into the adjoining garden). We do have a small amount of lawn left and these leaves are collected and used on the steeper slopes where exposed soil is susceptible to erosion.

I found this amazing Fawn Sphinx Moth Caterpillar (Sphinx kalmiae) last week, and like many moth and other insect species it will overwinter under leaves.

Ever wondered where on earth in a surburban setting of all lawn can these insects find a warm and protected enough place to survive Minnesota's winters?

Some insects will find winter homes in hollow plant stems and plant debris, rotting wood logs left on the ground or standing but under leaves are one of the most commonly listed places in my field guides.
For this reason, we don't cut down any of our native perennials or grasses until late spring after most insects have emerged. Besides, it creates very nice winter interest having the skeletons of last year's landscape stick up through the snow.

We have salvaged many old logs from our neighbor's property (with their permission) because they were to be hauled away during their property construction. We have used them throughout the yard as nurse logs, planting shrubs and perennials around them. These plants always seem to do significantly better than ones further away from the nurse log.  The nurse log provides the soil with valuable nutrients and helps hold moisture which the growing plants love.

This spring, I looked outside into the backyard and we had a Pileated Woodpecker pecking away at one of the first nurse logs we laid in the yard 4 years ago. It probably took some time, but the log most likely has many types of insects in it now that attract the woodpeckers. We now have enough of a shrub and herbaceous layer around the log too that makes me believe that the Pileated felt comfortable enough to settle in for a while and peck at the log.