"Locust trees are species of Robinia and Gleditsia"
They are two completely different trees. The vessels in the Robinia which was named after the first arborist, Robin (sic?), are arranged in a ring porous fashion. E.g., Oak, American Elm.
Gleditsia has vessels diffused such as in maples, birches, beeches and so on.
See wood types here:
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first thing to establish to answer your question, is are you referring to black locust or honey locust as far as comparing them to acacia.
There is a picture of wood in a cross section of honey locust here "Woody Root / Woody Stem"
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black locust, robinia is similar with respect to vessels as that of oak.
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can be found here (note this site the wood may be symplastless compared to samples by SHIGO such as that of honey locust was wood that maintained a symplast.
I have not dissected a acacia. If you could send me a woody stem sample I will prepare it and place it under the microscope and see what wood type it is. That can reveal a lot about the tree and its water requirements.
Sincerely, John A. Keslick, Jr. Arborist
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Beware of so-called tree experts who do not understand tree biology. Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us that we are not the boss.