Walnuts for riparian restoration work



May 15, 2008


So here is another learning experience for me...

The nuts of nut baring trees are collected in the fall.  Viable nuts will sink in water while nuts that are not viable will have airspaces in them and float.  To test the nuts, dump them in a bucket of water, and compost the floaters.

Normally squirrels will burry nuts, forget about some, and those forgotten will grow into new trees.  A nut buried over winter will go through stratification, which includes a cold winter cycle.   To simulate this - storing nuts for the spring planting - you put sand in a pale, then a layer of nuts, then a layer of sand, then nuts, etc, making sure the last layer is covered with an inch or so of sand.  A bit of water to moisten the soil somewhat like out in nature, and check from time to time making sure things do not dry out.  You leave them in a cold storage over winter my garage would have to do for the last point.

I collected nuts in the fall of 2006, and went through the steps above, with the plan of giving these nuts to environmental groups for riparian restoration work in the spring of 2007.  People would simple plant them like planting bulbs.  Squirrels surely would get some, but hopefully there would be new seedling started.  Trees grown form seed in this way would have much healthier root systems than trees transplanted from pots, therefore this method of getting trees into the environment would be a better way of doing things, easier work for volunteers, and less costly.  Two hundred walnuts cost about $50.  Walnuts collected by environmental group volunteers priceless!

Somehow, I never got these nuts to any of the groups around here, and the pales with nuts sat in my garage.  I was disappointed by the work input done so far, with no results, and the wasted effort.  But then a few seedlings germinated in the spring, right in the pale!  I transplanted them to pots with the intent of letting them grow for use in projects during that Fall.. 

When nuts germinate, the nut provides nutrients to the new seedling until the flesh of the nut is used up and the roots take over.  While the nut is still attached, these seedling are vulnerable to squirrels.  I should have known it the squirrels took less than a day to up root all the seedling, killing them while going after the nuts.

By about mid summer, no other seedling had germinated so I was about to discard the rest of the nuts, but I decided to test float them again just to see.  To my surprise, almost all the nuts sank, meaning, they're still good!  OK, I layered them back into the pale and left them.

Fast forward to the spring of 2008.  I forgot about the nuts, not really expecting any viable nuts to still be in that pale.  To my further surprise, I now have a pale full of Walnut seedling.  WOW!!

Im now faced with a dilemma - I need to find some kind of wire mesh that I can secure to any pots I plant these seedling to, either that, or try planting them directly into a field out in the open away from squirrel populations.

The lesson learned is that walnut seeds are vary resilient, they do not all germinate the first year, and if reviewing a site that had walnut tree nuts planted, one would have to check back for at least a few years to determine if the project was a success or not.