The Berberis Shrub Base, a Lignotuber
B. trifoliolata subterranean lignotuber, c. 6 x 6 inches. The red line approximates the soil surface.
To determine the root system of a mature B. trifoliolata bush I received permission from the Kopponen ranch in Dripping Springs to extract a larger bush. Previous owners of this ranch had employed buldozers to remove Berberis plants from rangeland, and Viktor Kopponen agreed to sacrifice a plant for my study. I have not extracted a comparably large specimen of B. swaseyi or a hybrid, not wanting to risk destroying them, but my overall impression is:
- B. swaseyi does not share the many-stemmed base habit of B. trifoliolata, and older plants would not reveal a significant rootstock.
- Hybrids seem to vary a great deal in this respect, and at least some would have a well developed lignotuber.
The root
B. trifoliolata's root has a dark orangish-brown, furrowed bark. Inside, the wood is deep yellowish-orange and radiate — strongly resembling stems.
B. trifoliolata root details.
Extracting the Bush
First I selected a moderately large bush with numerous stems at the base.
Next I removed the branches above c. 6 inches from the ground. This revealed 46 stems of various sizes/ages coming from the ground.
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| Bush with stems numbered in red. | Distribution of the red numbers in the image to the left. |
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| Detail of the area outlined in red above. | |
Then I dug a 1 foot ditch at a distance of c. 1 foot around the stems and then cut in from the sides to remove the bush. The thick main root below the lignotuber went directly down into the soil, very deep I assume. The roots were torn in the process revealing a deep orange color. [Compare the yellow stem cuts above.]
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| Roots covered with black clay. | As much dirt as possible removed. |
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The remaining dirt was carefully washed away.
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| View from the top. | View from the bottom. |
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