Should Queen Palms be trimmed?
No, they do not need to be trimmed. They are self cleaning palm trees.
As new leaves form, a white, pale tint seems to come from inside the leaves. Where fronds separate from the trunk, it becomes web-like and dead. Untreated this whiteness grows up the frond until it is dead. Palm frond weakens at the base and can grow warped off to one side. Is it a pest or disease? Can it be treated? My location is Houston, Texas.
It sounds like a pest. There are a few it could be and those are scale, spider mites and mealy bugs. These articles will help you determine which it is:
https://www.gardeningknowhow.com/houseplants/palms/sticky-palm-tree-leaves-treatment-for-palm-scale.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/spider-mite-treatment.htm
https://www.gardeningknowhow.com/plant-problems/pests/mealybugs-white-residue-on-plants-leaves.htm
There is a white substance coating the leaf stalks quite heavily on some. The candles on one have died and also the berries have died. They were planted in the spring and seem to be declining. There is some new growth but as soon as we cut off a dead leaf, another starts to yellow and then turn brown.
It sounds like a pest. There are a few it could be and those are scale, spider mites and mealy bugs. These articles will help you determine which it is:
https://www.gardeningknowhow.com/houseplants/palms/sticky-palm-tree-leaves-treatment-for-palm-scale.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/spider-mite-treatment.htm
https://www.gardeningknowhow.com/plant-problems/pests/mealybugs-white-residue-on-plants-leaves.htm
Neem oil will help in treating the pest, regardless of which one it it. Here is more info: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
My Queen Palm suddenly looks stressed and fronds start to brown quickly. New spears appear but are not as robust as usual.
This article will help. The article is about Sago Palms, but the same principles apply to Queen Palms as well:
http://www.caes.uga.edu/extension/lowndes/anr/documents/sagopalms1.pdf
I was horrified to see that cut worms are eating away at my beautiful Queen Palm. What can I do to save this beautiful 30 ft Palm?
You can buy a substance called Bt (short for bacillus thuringiensis). It is sold at many garden nurseries. It is a natural bacteria that kills caterpillars of all kinds. This should help eliminate them.
You can also use neem oil. It is not a quick kill pesticide, but causes the caterpillars to stop eating and they starve to death. The nice thing about neem oil is the tree absorbs it, so even if the worms can burrowed into the tree, the neem oil will still reach them and kill them.
Both of these substances are harmless to people and pets.
I want to know how to get rid of the ants in 20 foot queen palm tree. I was trimming my queen palms for spring and I noticed there are little holes in the queen palm.
You might want to consult a professional exterminator to determine what kind of ants they are, and how to treat them. If you want to try a home remedy, this article will help you: https://www.gardeningknowhow.com/plant-problems/pests/insects/home-remedies-carpenter-ants.htm
I have Queen palms about 15 feet tall. What should I be feeding them and how often? I live above Orlando FL.
You need to fertilize once a season in spring, summer and fall (skip winter) with a fertilizer that has an NPK of 8-2-12 as well as containing some magnesium. They do sell special palm fertilizer that can make things easier.
This article is a good primer on queen palms, and will give you or link you to all the information you need: http://edis.ifas.ufl.edu/st609
Additionally, you can get information from the county extension service. This link will help you find the nearest office:
https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm