Walnut tree removal

Excavator lifting up walnut tree after it is pushed over.

This last week we had 15 acres of our walnut trees uprooted. Walnuts only last so long and then they have to be replaced. An orchard can be nursed along to a pretty old age, 60 years or more, but the quality and quantity of the nuts will continue to decline to a point where the costs of maintaining the orchard will eat up most of the returns from the crop.
Replacing an orchard is a huge job. Walnuts are large trees and they require big machines to pull them out. We hired a company to do ours. They have a large excavator that is big enough to actually push the trees over. After the trees are pushed, the excavator picks them up, shakes off the dirt and lays them in neat rows. Later, after the uprooted trees have had a chance to dry, they are shredded and the chips sent to a co-generation plant to be used as fuel.
The next step in the process is to remove the roots. Walnuts have big root systems that spread out over a wide area. It is important that as many of the old roots are removed as possible because they harbor plant diseases that will affect the new trees when they are planted. A large bulldozer such as a Caterpillar D8 or D9 with rippers is used for this task. The root pieces brought to the surface by the bulldozer are picked up by hand and removed from the field.
Once the old trees and roots have been removed, the soil must be fumigated to destroy pests and diseases that are in it. We attended a class recently regarding this. It was amazing how many disease organisms were in the soil just waiting to eat the new little trees we need to plant. Soil fumigation is an essential step – walnuts cannot be successfully planted without it.
That is actually a problem these days. State regulations have strictly limited the amount of fumigant that is available for use. This drives up prices and in some cases forces the use of inferior materials. It may even mean we have to wait an extra year before planting new trees.
To properly fumigate the field, the soil must be dry. There are strategies to dry out the soil. One is to plant a grass called Sedan grass. This grass has long roots that pull up moisture from several feet deep in the soil. After it is matured, it can be mowed, bailed and used for animal feed. The fumigation process can be started after the grass is removed.
If everything is properly done, the ground will be ready to receive the new trees. Spring of 2010 will be the soonest we can plant. But more likely it will be spring of 2011.
Looking ahead it will take four or five years to start getting a crop after the new trees are planted. It really is a lot of work and expense to replace an orchard.