Monday, May 30, 2011

An Old Walnut Grove

The most dominant tree on our property is a black walnut.  It stands just off the drive at the head of the pasture.  Anyone who visits the Einsel House passes under its shade.

The first time my grandpa visited the house he walked through the rooms in the old stone portion, taking in all the beautiful walnut woodwork, and he commented, "This must have been an old walnut grove."  Then he explained to me that walnut trees are toxic to other plants.  He said that as walnut hulls decompose they spread a poison through the soil around the tree.  This poison kills off the any non-walnut sapling that has the audacity of trying to take root within the black walnut's domain.  Over many years, the first 'mother' walnut tree to take root in an area would choke off other encroaching trees, providing benefit to her own walnut saplings.  Once grown, those saplings would repeat the favor for their own saplings.  Ad infinitum, at least until the axes of Noah Rhinehart's generation entered the picture. 

Because of this, grandpa explained, by the time the Rhineharts arrived here it would have been very rare to find a single full-grown walnut tree.  Instead, where there was one walnut tree there were likely many walnut trees - "an old walnut grove."

 In the past I've never cared much for walnut trees.  (They're messy.)  But after hearing grandpa's story, it seems appropriate in way that it's a black walnut guarding the drive to the Einsel House.  I see her as that protective mother, still looking over the other walnuts - albeit they are no longer trees, but the doors, stairs and trim in the house that she is guarding.

Lately, grandpa's story had been quietly repeating in the back of my head for a different reason.  Our 'Mother Walnut' is the first thing visitors pass as they approach the house, and she was looking a bit abused.  There is not enough space for the lawn mower to pass between the tree and the pasture fence, so that area had become a catch-all, the most convenient place to toss branches blown from the tree or stones pulled from the pasture. And there are apparently plenty of weeds that are immune to the black walnut poison.

So the last couple of weekends I've worked at clearing the area under our black walnut tree.  My original plan was to plant ivy under the tree, but after considering grandpa's story I decided it would be wise to investigate black walnut 'poison' before planting anything directly under our tree.  I learned that the poison's real name is juglone.  As grandpa said juglone is in walnut hulls, but also in the tree's roots.  And there is a relatively limited number of plants that are not affected by juglone.  Unfortunately, ivy is not one of those plants.  In the end, I decided on ajuga ("chocolate chip").

The ajuga was planted beneath the tree yesterday.  I moved all of the limestones from the pile under the tree, but left a small pile of other rocks for the ajuga to grow around.  So hopefully next spring our walnut tree will be surrounded by a bed of delicate blue flowers.

1 comment:

  1. We have a similar challenge planting under redwood trees - their droppings are super acidic, so most things don't like to grow under them. I am going to look up ajuga + redwood - thanks for the idea! I'll keep my fingers crossed for blue flowers for you next year.