A Recycled Almond Orchard May Need More N the First Year

Almond Orchard recycling involves chipping up the entire tree and then spreading the chips back into the soil.

Once those chips are incorporated back into the soil, there is a question as to Nitrogen availability in that soil that the trees may need.

Mae Culumber as a UCANR Nut Crops, Farm Advisor in Fresno County. “The trees may need more nitrogen. We're trying to fine-tune that number right now, but it might be somewhere around 45 pounds per acre, when a normal first leaf almond orchard would probably get somewhere around 28 pounds to the acre,” Culumber explained.

“We think that in the second year that you can just return to your normal fertilization plan like you would any orchard. So that enough of that carbon that gets broken down in that first year, that could be immobilizing the fertilizer that you're putting down should be able to manage things, normally,

“The problem is that chips may be robbing the soil of nitrogen, making it unavailable for the trees. We have microbes in the soil that thrive on carbon, but they also need a portion of nitrogen,” Culumber said. “And so when there's a really large imbalance between the levels of carbon and the levels of nitrogen in the soil, the microbes will scavenge all of that nitrogen up that they can find, and continue to assimilate all that carbon.

“And when the micros die, they excrete the nitrogen, making it more available for the trees,” Culumber said.