On Kansas State University worst tree list is WBJ.

* Rocky Mountain juniper, including the Wichita blue juniper variety.

My condolences to Wichita for having a variety of this tree selected as a namesake. Both Botryosphaeria canker and Cercospora needle blights are time bombs on the species.

Mine looked like hell for years until I finally put it out of its misery. (out of my misery too.)

i put 5 such junipers.. not just WB out of my misery in the last few years .. a couple cool variegated one to boot...

you said .. AND IT HAS DONE VERY WELL .... i would dispute that.. since it acquired a disease .... do not feel sorry for it .... it isnt worth the cost to fight the problem.. if you even can ....

be done with it ..

ken

The "...small, brown coccoon-like things hanging from the branches." are bagworms.

bullthistle, do you have a link to that tree list? I can't seem to find it on the K-State research and extension website.

As with all Junipers you can greatly reduce the susceptibility to most all of these potential diseases by planting them in full sun in an area with plenty of air flow and good soil drainage. All of the Rocky Mountain Juniper cultivars I've seen having problems with one or many of these diseases are inevitably planted in part sun to light shade and/or a wet spot.

Here is a link that might be useful: List of dozens of different Juniper cultivars and their disease resistances

the ones that became diseased in my garden ... are on pure sand ... [complete drainage] ... absolutely full sun .... and basically windy prairie ... and presumable came healthy ....

my biggest problem .. is all the other non-conifer neighbors who have diseased plants ... that i can not go remove ...

ken

Mine too was in full sun and sandy, very well drained soil.

In your cases, I'd speculate that like Ken said, nearby plants may be infected and thus it wouldn't be too difficult for it to jump over to your plants. But I also think it could be periods of cool wet weather during the growing season which might also play a role. Do you guys ever get days of cool wet weather in June, July, or August? When I say cool, I mean temps below mid 70°'s and perhaps cloudy(where the foliage doesn't dry off). It's also possible that many of these cultivars suffer in high humidity climates that are also not that windy. While the Eastern 2/5 of Kansas does have high humidities in the summer(dew points typically range from 65° to 75° on most days, right now outside temp is 91°F, dewpoint is 78°, with a heat index of 106°F at 2PM for instance) it also tends to be quite a bit more windy than the Eastern US.

Also, Ken, windy? prairie conditions?...Michigan??? You have photos of the windy prairie up there? ;-)

I forgot to add, that if you looked at the list of Juniper cultivars in the link I provided, it does appear that at least some cultivars of Rocky Mountain Juniper do quite well at resisting these diseases and you might want to look into replacing your Wichita Blue with one. Also, the Chinese Juniper(Juniperus chinensis) cultivar 'Blue Point' is highly resistant to most all of these diseases and has become very commonly available in recent years. It looks relatively similar to WB too, with a similar growth habit and color.