..echoing alienteaparty, this tree (and a. obtusifolia) are quite slow growing in the wild..relying on natural rain, the trees in your photo are easily 20 years old..large trees provide the seed stock for the future, and only a very small % of seed ever germinates naturally..in cultivation with lots of fertilizer and water, growth rates are much faster..
..at over 1% in the leaves, why would you need to use bark?..this just seems disrespectful of the life form..and not very symbiotic..
if you have to use bark, at least just prune a large branch and let the tree live on..like, how much dmt do you and your friends need? tree killers are usually greedy salesmen..
i think the majority of long-term students of acacia would agree with me..this more caring approach is more likely to lead to long-term 'friendly' experiences..
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