I have tried something else. As we are having a very mild winter here in Belgium (understatement) I thought it would be a good idea to put the tree outside again. That will take care of these creepy crawlers. Some December rain and wind will blow the cobwebs away! Lets hope it does the trick. The next two weeks they do not forecast any frost day or night. Need to keep an eye on it mind you... I will le you guys know. Thanks for the comments.

Genna, that's great. but I don't think there is going to be any way to help you with that kind of answer,,( It looks dead...Is that out of the pot? How long did you let it stay that way? Is it in a pot now? What kind? What kind of soil? What kind of light? When or how do you know when to water? Do you fertilize? What do you use? Do you let it dry out to a wilt? Do you water when the soil is still moist? Where do you live, well what state? What growing Zone? Did you ever grow it outside? What kind of window do you keep it in if in the winter? Just a few questions

I am not in AZ so can only offer anecdotal info and perhaps a guess or two for you... perhaps others in your area can chime in and help. Heat (alone) - probably not. Heat and lack of water during the heat wave - possibly. Intense sun on bare limbs - possibly. A friend of mine in Scottsdale lost his mature lemon tree rather suddenly years ago. It was not heat, but stress from early season pruning (evidently the landscaper just did not know citrus too well). The shock of a significant trimming killed it. In my areas, lemons facing south and west all seem to do just fine, they love the intense sun... but must get enough water. My lemon leaves never show any sun scorch... unlike other cultivars. If you want to save the tree, paint the (sun exposed) trunk and limbs asap with a 50/50 solution of latex paint/water. I'd avoid pruning right now,,, some branches may come back in a surprising way. Mulch and cool the roots as Susanne suggests. And, make sure those light strings aren't strangling it anywhere. Let us know how things progress... we love updates and pictures .... good luck - George

Spreading the Mulch A 2- to 3-inch layer of mulch spread around the base of each citrus tree is enough to hold in moisture, regulate the soil temperature and prevent weed germination and growth. The University of California San Diego Cooperative Extension recommends maintaining this layer constantly throughout the year. Preventing Root Rot A common cause of root rot is lack of oxygen exposure, which can occur if the mulch is spread too close to the citrus tree’s trunk. To help eliminate the threat of root rot, spread the organic mulch at least six to 12 inches away from the citrus tree’s trunk. This prevents excessive moisture retention around the roots and allows for proper air circulation.