Answer: A 30-40 foot tall palm is probably very well established and getting along with just the water it receives from rainfall and whatever water you use to irrigate your landscape. It will have deep roots and probably won't need feeding. Remove the fronds as they brown, but don't bother to shave the trunk. The "boots" as they are called, will fall off on their own and while they are there will help keep the trunk from sunburn or physical injury. Lethal yellowing is a systemic disease caused by a bacteria transmitted by a planthopper. The first symptoms are premature drop of the fruit, followed by new fronds turning yellow even before they finish emerging from the crown of the palm. Once the disease has affected the palm, there's not much a homeowner can do. Injections can be made to slow the progress of the disease but those are done professionally. For more information about palms and their diseases, contact your local cooperative extension office. They have lots of publications that you might find helpful. Good luck with your new landscape.
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