Monday, February 20, 2017

Thinning more Kanza trees

      For the past six years, we have been progressively thinning a three acre block of Kanza trees. This week, we removed trees within the Kanza block in areas where adjacent trees were competing for sunlight and according to our thinning plan (photo above).  During this sixth year of thinning, we cut down 15 trees; the most we've removed in a single year. The original tree planting had 144 Kanza trees. After removing 15 trees this year, we'll be down to 96 trees in the orchard.  The first thinning will be complete when half the trees have been removed and we are down to 72 trees in the 3 acre orchard.  

    The figure at right is a map of the Kanza block as it appeared before we cut any trees this winter. Each tree is depicted by a green circle with a diameter proportional to the tree's trunk diameter. As you can see, tree growth has not been even across this orchard. Tree growth has been fastest in the northern 1/3 of the orchard.  As a result, we've thinned more trees in this area of the orchard. However, trees in the southern half of the orchard continue to grow and will require thinning eventually.

    We removed 15 trees from the Kanza Block this year.  Trees cut down are marked by black circles on the map at right. We thinned trees over the entire planting but most removed trees were located in the middle third of the orchard.
   Up to this point, I've been pleased with this progressive approach to orchard thinning. By taking out trees on an as-needed basis, we have been able to maintain good light penetration into the orchard while preserving high yields