Baby almond trees root development study

Plant type: 

Baby almond trees, two species, Padre and Butte.

Application used: 

As described earlier.

Location: 

Various commercial almond orchards in the Central Valley, California as well at in greenhouse trials.

Our observations: 

By testing various ingredients of our "John's blend" we understood, which of the ingredients  influenced root development in a most positive way, both in the green house and in the orchard. The treated trees showed a much larger developed root system and also larger (longer) roots compared to untreated trees.

Image:

The image shows root measurements conducted in the almond orchard after the roots were uncovered and cleared. 

By testing various ingredients of our "John's blend" we understood, which of them influenced root development in a most positive way, both in green house and in the orchard. The treated trees showed a much larger developed root system and also larger (longer) roots.

Thank you to Jason DeGroot of Living Soils company, for helping with the almond tree root inspection.

Results:

The “two-hole” method produced trees much larger than trees planted with “one hole”.

We also observed that the trees planted with “one hole” were nearly all “imbalanced”, i.e. the S side of the trees had longer and more branches than the N facing side of the tree. We wondered: Might this be due to the method of planting? 

We wondered if the root balls of the 1-hole plated trees would be sufficient to hold the trees up against strong winter winds, when the soil was saturated/weakened by rains. So we repeated the root ball investigations, using the same method described above also with the 2-hole trees.

With 2-hole tree planting,  the roots into the S hole were 3-5x more numerous than the roots extending N, and the S roots had thicker diameters. Most notably they went deeper than 3’ and answered the question “will the roots be strong/deep/broad enough to stabilize the trees over 12’, after the soil is saturated?” The answer is “yes”. 

The longest roots roughly extended to the tip of the longest branch above that root. In this case, about 30” length under the 30” branches (i.e. S side, where the nutrients were added at planting), and about 12” length under the 12” branches (N side of tree, did not receive nutrients at planting). Unsurpringly, both cases roughly matched the dripline above ground. 

  This leads to a pair of additional questions:

1) Do nutrients taken up by roots, travel vertically to leaves on that side of the tree, or do they somehow “mix/crossover”?

2) If the tree doesn’t find water/nutrients in one direction after initially coming out of dormancy, will the tree continue to send out “scout roots” in that direction in subsequent years, to see if conditions have changed? 

3) If so, might we effect tree growth and tree balance, by soil injecting nutrients into the previously “barren” area of that tree?

Acknowledgements: 

Thanks to Kenn Rapp for allowing this work in his commercial orchard. Thanks to Jason DeGroot (Living Soils) for his time, and for the use of his pump and soil washing. Thanks to Sasha Novitsky for his help.