Answer: Last summer's heat and drought was very hard on many plants. Japanese maples in particular need an evenly moist yet well drained (meaning not soggy) soil and it should also be rich in humus or organic matter. The tree does not, as a rule, do well in reflected heat as may have happened using the stone mulch. For this reason, an organic mulch woud be preferred, especially since it will also help to feed the soil as it breaks down. Another aspect would be to check the pH; these trees need a somewhat acid soil. I am not certain why the tree was dying back. It could be the result of drought or heat stress, but it could also indicate some other type of problem. You might want to consult with a professionally trained arborist or your County Extension (461-1000) for some further troubleshooting.
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