Cupressus Nootkatensis/Callitropsis Nootkatsis. ie: Weeping Alaska cedar

HI Folks: An welcome to myself new here, really looking forward to this 'great professional forum', an experienced gardener, beset with an lot of eastern fungus, set on mature varied trees, in mature garden. But I'd like to reference the most severe to-day. Front garden, 3x25 ftr.s, about 15 yrs. or so, fairly recent, on the main tree-an pestalotia twig blight, [P. funerea]., brown tips by fungal infection, an few years onset. Now, in progression, thru this 08' springtime, looking like an drought problem, [yet much onset severe rain's/water]. Could show pic. to an leaf/thuja, getting quite severe, kills ind. needles, brown from tip progess, distal to trunk, the whole of the 'hanger/stringer', turning black, and falling off, thus killing the nut/fruit. Denuded all, outside inwards alarmingly.
I'm reminded of the 10 yr. old pandemic, & world wide spread, of the S.Cardinale fungas, initiated, or at least observed on the sth. west coast, reminds me of some of those symptoms, but slower onset.
Of opinion, were very strong plants, good soil, and well watered, cared-for, maybe 20 yrs. The twigs falling off more rapidly, but maybe only 2% of the tree's. Wondered, if recent personal construction interferred with the sensitivesurface oriented small roots system.
Had moved some 2+ tonnes of old granite cobble stones, from resident front ditch, because of expected sewars/construction, to an winding front lawn path, midstream between this tri-cypress locations. The larger closest to the resident, the bed for the stones, was/is notsand, used inadvertently, 2+inches, of white type 'screening's', and curious if the ph, or mild digging there, did impact the 'outer circumference of roots system severely'. Suspect not, but the onset of symptoms, suggest that, as well placed, 2 tonnes of round river rocks, fairly close to one of the lateral frontal trees, which suddenly has same onset symptoms, did restore the grade, which may have aggravated non postive water seepage, for I have an frontal timber retaining wall, established.
I've invited some aborists, in for inspection but there quite busy, with an lot of summer projects, in the Ontario, Toronto zone location. I quite stupified, about the whole matter, as the triumverate cypress trees, are the piece de resistance, of the frontal landscaping, and for our appreciation, much loved.
The other thing, really wondered, if 'mites', were busy for an few years, and show tell their activity by eating their way down, to the bottom, thru to this now near end July, to colonize the bottomed earth. If so, how do I better recognize that culprit, and if sois spraying Diazonen, or benomyl, [or acceptible government insecticide] reasonable. Or is this an soil type proble, or the earlier fungal consideration.
An better, main type nursery, consider, it an drought difficulty, but in an 1 week plus, the disease is more severe, could send picture, perhaps can get some viewpoint next week. Meanwhile searching here, everywhere. Would consider response, as I'll, continue to come back to the/this forum, and search it's contents. I'm fertilizing, the Nootka Cypress, but perhaps to much nitrogen, virtually, I'm away past the early onset of twig blight, but/yet the top parts of the trees are simply OK/normal. There could bean number of problems. either induced by me, along with something else. We shall see. I am kannutipper@gmail.com. So Long, and Thank Tou.. + k