Really need to see photos to correctly diagnose disease issues. Rapid branch dieback is often attributed to verticillium wilt but leaves decaying "from the inside out" doesn't really fit nor does the branches blackening.....at least that rapidly. Post photos of the tree with as much of a close up of the affected area/plant tissue as you can manage and we'll do our best. If it IS VW, there is nothing you can do.

Cool pics! I put out an Oriole sugar feeder and orange slices every year and this year saw a male Baltimore Oriole drinking at the feeder once very early in the morning. Would be SO wonderful to see them around Thanks for filling out some of your info, but it would be great if you could also put your camera and lens info on your MyPage so people can refer to it when they admire your photos

If they don't scrape off easily, they are just lenticles, which are just pores along the stems and which Limelight of any of the paniculatas has the most distinctive and visible collection. If they do scrape off easily, they could be scale but they look much too regularly or evenly placed for scale.

lavender is a hot topic on this forums for many years .. the vast majority of us can not grow it.. and gave up on it years ago ... for a multitude of reasons .. usually associated with winter drainage ... the roots just dont like cold damp soil .. for those of us in colder climes ... the fact that you have gotten it this far.. is a gold star .. and after that .. well ... it doesnt surprise me.. its becoming a problem ... its getting old ... most of us might not call it a long lived perennial ... if you should fail.. revel in your success .. and dont look back ... and every time i type this.. up pops the 2 ro 3 people who cant beat it back with a stick .. and swears its a weed on some level ... all the power to them.. and i hate them.. lol ... this isnt a rare and expensive plant.. sooner or later.. just get another and get rid of this one .. in other words.. dont spend 20 bucks trying to save a plant you can go buy for 5 bucks ... [i havent been buying things for a few year.. can you still buy plants for 5 bucks??] ken