If you think it's something other than drought damage clip representative samples and take them to your nearest USDA Cooperative Extension Service branch office for diagnosis. (You will have to be able to get there during something like M-F 9-5).

You can locate your county's Cooperative Extension Office with this interactive map: http://npic.orst.edu/pest/countyext.htm

Take images of an entire tree, perhaps several trees in a row. Such images reveal the distribution of the problem on a tree -- which often provides helpful diagnostic clues.

The preferred sample to take to the office is affected growth still connected to either unaffected, or newly affected, growth

PS: County Extension Service offices are affiliated with state land grant universities, not the USDA.

Personally, I'd spend the money and consult with a certified arborist.

Extension Agents are generally well educated and have good experience. But they are primarily there for commercial enterprises. If you can get one to pay attention to you, it's worth whatever effort it takes, within reason. But a certified (ISA) arborist is where I would go.

And it's called cooperative extension because it is a partnership between the USDA and the land grant universities (a result of the Smith-Lever Act and the Morrill-Land Grant Act). In addition, the federal agencies partner with local state and county entities. I have had to give lectures about this...

In Tennessee, the ag extension system provides many services to non-commercial sectors of the community, and is available for consultation to private, non-commercial entities (eg. homeowners, home gardeners, etc) just as much as for large commercial farming operations. Looking at Georgia's extension program, I'd say it's safe to say that it's the same there.

Expertise varies from extension office to extension office and from agent to agent, but that can also be said, and probably to a much greater degree, for ISA-certified arborists (especially when it comes to something like IDing pests or disease issues). I would tend to trust a diagnosis from an extension agent slightly more so than one from an "average" ISA-certified arborist, but I would do my homework (research, second opinion, etc) before accepting a single diagnosis from either source. I've seen lots of incorrect diagnoses, especially from certified arborists.

In the mid-Atlantic, some Cryptomerias just never look good on poor sites. Even ones at, for example, the University of Delaware, where they at least had a better chance of being properly planted. When I see large, healthy cryptos along the eastern seaboard I know I am seeing good, deep soil. Sick ones are seen in places like shopping center embankments made of 100% red clay fill. I have good, deep soil and none of my various crypto cultivars has ever shown even a bit of this problem EXCEPT for 'Elegans'; which I'm beginning to wonder might have some kind of a long-term adaptability issues with non-maritime or Asian monsoon climates. Pretty sure I've never seen a great looking one on the east coast!

Yours are typical of what I've termed 'mangy cryptomeria disease'; which might be caused by an actual insect or organism, but only bedevils those on less than optimal sites. IIRC the National Arboretum's Scott Aker who used to have a column for the Washington Post, had some articles years ago about this problem and how to prevent it with winter oil sprays. Again, IIRC.

I agree with brandon to go with an extension agent in this case. Should not be hard to find one familiar with this common non-native tree and its use in Atlanta.

see comments here:

[https://www.houzz.com/discussions/mangy-sugi-disease-dsvw-vd~5046792[(https://www.houzz.com/discussions/mangy-sugi-disease-dsvw-vd~5046792)

Generally, although it likely varies, the Extension offices exist to serve commercial agriculture and horticulture and deliver their non-commercial advice and counsel through the Master Gardener programs. Since MGs are all volunteers (and I was one for 12 years here, where I worked out of the Extension office) there is a HUGE variation in skill and experience. The MGS have the Extension resources at their disposal, however. In Sonoma County, we have Extension professionals who specialize in range management, shellfish farming, grapes, stone fruit, etc. It's amazing how much knowledge they all have. It's just tapping into it that can sometimes be tricky for a homeowner.

I have long-standing relationships with several ISA arborists and that likely colors my reliance on them. Their expertise is beyond that of the extension folks when it comes to ornamental trees. But again, individual situations may vary. The actual Agent (in CA we call them Farm Advisors) brings his or her own approach to the office. Our Farm Advisor when I was an MG was a stone fruit expert so we all went straight to him for any questions about olive trees, whether ornamental or producing. He generally could answer the questions in his sleep!

Yeah, second opinions are good. I have had my arborists disagree with each other, too!

Agree w/david -- many cryptos look sorry on certain sites w/alot of inner branch death. Saw it at the VA State Arb. Not confident there is any solution, except that it usually doesn't kill them.

this is one of the reasons that a monoculture sometimes just doesnt work out.. when one becomes a problem.. there are good odds that all will end up with problems ...

these are trees.. problems happen in tree time ... it might take 10 years for it to fail.. or it might not fail ...

but ... if it were me ... i would start planting a solution to total loss ... if thats a possibility .. we could discuss how to do it ...

e..g. .... i might remove every 3rd one.. and replace them.. with just about anything else ... so that in ten years.... they will come to size .. while maintaining most of the site block that i presume is the reason for such ...

an alternative.. would be to plant out into the lawn a bit.. but you might have trouble removing those behind in the long run ...

or ... combining both.. cut every third flush to the ground.. and plant the replacements a few feet into the lawn ....

btw ... is there a fence behind them.. before the neighbors lot???

ken

Every extension service office has access to a plant pathologist or pathology lab. These may not be onsite but certainly accessible by any of the extension service staff (and often by the general public as well, if you research your local services). These are science professionals that routinely monitor and track local plant pathogens and pests and typically write the publications that arborists and other horticulturists (and the MG's) are trained with.

I tend to agree with David on this one...."mangy sugi disease" shows up here as well. although not with high frequency. In this area, I would attribute much of the cause to drought stress. And it tends to be more of an issue with older, more established trees than it is with newer plantings. I assume younger trees just get more attention :-)

Yep they are university experts. We had one who did a plant pathology clinic every Saturday at UC Botanical Garden in Berkeley. It was fabulous. Unfortunately he died and his successor did not keep up the tradition. Hands on ID with an expert is such an incredible learning experience.

Here are Georgia's offerings:

http://extension.uga.edu/topic-areas/weeds-diseases-pests/plant-pest-disease-management.html

http://extension.uga.edu/topic-areas/lawn-garden-landscapes/ornamentals.html

I think they were originally planted too close together. Now, they are competing with each other for sun and water. The crowding also causes a lack of airflow through the branches, which can predispose to fungal infection. You can see similar issues affecting many landowners in the Atlanta area with both Leyland cypress and Cryptomeria. It's an age old problem - trees planted closer together provide more immediate screening, but in the end the trees suffer. Trees planted further apart thrive, but it can take a decade to effectively screen a property.

I would take Ken's advice and remove every third one. If immediate screening is necessary, you could put some placeholder plants in between. Just be prepared to remove them when the Cryptomeria get bigger.

I'd get a soil test. Find out whether this is an area that any plant could survive. In the meanwhile I'd aerate and then spread a few inches of manure.

I don't see how a drip system can satisfy their Summer water needs. These are 35 foot trees with an extensive root system planted fairly close for their size. Genetically, they're set up for summer monsoons. That's why they do better here in good deep soil with drainage near, but not at, the bottom of slopes.

I tend to think it's drought stress. Atlanta's climate doesn't duplicate Japan's Summer monsoon conditions and a drip system isn't going to make up the difference.

It very well could be drought stress, but these plants are remarkably drought-resistant here in Georgia. Every tree has its breaking point, of course, though I haven't reached it with mine, yet (and that includes some brutal summers here over the past 8 years). As I noted above, however, crowding can exacerbate any problem.

I have had good success with Cryptomeria here and our summers are bone dry, not just no rain but ambient humidity in the teens. And I water by drip irrigation. Mine are all 10 years or less in the ground, though, so the long term results are still to come.

For what it's worth, Tom Cox has noted in Conifer Quarterly how well his Cryptomeria have withstood drought and heat here without supplemental watering...