It sounds like you all have it figured out and all the advice is excellent as far as I can tell. I just couldn't help but agree that it absolutely looks like clopyralid or amiopyralid damage. I had a bad bout with it 3-4 years ago when all my homemade potting soil got contaminated by well composted alpaca manure. It took over a month to figure it out and I lost a bundle of valuable crops in the process. Clopyralid based herbicides have been banned in Oregon except for use on golf courses but then Dow chemical just comes out with Milestone which is amiopyralid instead. It's the same exact problem just with another chemical. To the OP, i'm afraid there really isn't anything you can do for the plants. If the cause is the manure, at least you're not contaminated forever. In the soil the chemicals do break down in a few months. But if left above ground the herbicide can last for years and damage sensitive plants (mostly tomato, potato, legumes) at tiny amounts (parts per million). Oh, I looked into a soil test for herbicide and it was extremely expensive. It's not an average soil test. Seeding some beans or peas is an excellent idea to determine if there's residue. -Mark This post was edited by madroneb on Tue, Jun 25, 13 at 23:20

Yes this is not normal. Now that you have posted a picture. I am putting a link below to a symptom called leaf scorch. Too late now but if you can't find the problem by reading the link bring some foliage to your local cooperative extension service next year. Nutrient problems with trees are almost always due to factors other than the amount of nutrients in the soil. Most soils contain elements in ample amounts for trees. Their is also a specific disease called Bacterial leaf scorch, which is different from the symptomatic leaf scorch. This does not look like Bacterial leaf scorch and is very unlikely to be so. Confused yet? Here is a link that might be useful: Leaf scorch.

That little brown dot is a scale insect. It is a little bug that has an armoured casing around it to protect itself. You probably have a big infection if leaves are browning and falling off, but don't worry, scale are common on citrus and easily treated. The first thing to do is pick the brown lumps off. They are matured scale and cannot move so should be pretty easy to get rip of. Wipe them off, pick them off or use a cotton bud. Their children, though, are mobile and like to hide in the tiniest little crevices. Oil sprays tend to be the most popular treatment method. One litre of water, half a teaspoon of oil (I use cooking oil lol) some citrus fruit zest, and some crushed garlic juice, and spray everywhere. And I mean everywhere - into ever tiny crevice, top and bottom of every leaf. You may need to treat twice weekly for 2 weeks or so to get them all. Alternatively, when I got a bad scale infection on one of my Meyer Lemons, I just bought a spray from a garden center and used the chemicals. I don't usually like chemicals but I didn't want it spreading to my other citrus. Always be wary about eating fruits after using certain chemical pest controls! Be vigilant - check your plant every week once the infection is gone for any sign of the hideous little things.

I have cut just the damaged/diseased part off of an Aloe before and that worked just fine. Be sure you are getting it all. 1-2 inches away should work. You know the drill - clean cutting utensil, sterilize between cuts. I also had those same spots on an Agave. I cut off the damaged parts of the leaves, just like with the Aloe. I then sprayed the plants (more than one were impacted) with a copper solution. I'm not sure that was necessary, but the fungus did not come back. Edit - agree with ewwmayo. Cutting more will ensure you get it all.