Well, DAMN. That's about as depressing as can be.

I'm sitting here with a mature garden of healthy roses, knowing that because some greedy fools brought them to Southern California, I may lose all of it.

Pardon me if I am angry.

You mean live RRD carrying mites exist in clouds in the sky? That is really bad.

I lose a rose or two to RRD each year, and have just depended on quick detection and plant disposal to keep it contained. So far that’s worked, but if they attacked my rosebeds en masse, my plan was to move to California and start over. Obviously , that plan will fail if these mites can travel over clouds and end up in CA anyway. Sigh.

BenT -- I hate to break this to you -- but they have been imported to California, and so, now, we too live with that threat.

They are not (as yet) widely-distributed. But if they come here, we're done. And AFAICS, they will, eventually, come.

Oh Jeri, I know they’re in CA, and I remember well the discussion where even Weeks had an outbreak. But in all the yards I see in CA, I’ve don’t see any RRD infected roses. Here in Dallas almost every group planting Knockouts (and there are thousands!) looks like some horror science-fiction disfigured RRD incubator. If you try to educate people about them, many have the attitude, ‘oh, I’ll just keep enjoying the flowers until the plant dies’. Ugh! I’m hoping maybe your drier climate is much less hospitable to the vector...I don’t see nearly spider mite issue (in general, not just RRD) in CA as I do in TX.

I bet these mites can't live very long up in the air with nothing to eat. Ann, how did they recover mites from clouds? Did they go up and take a sample of the cloud or did they look at the rain?

I'm not pooh poohing mites travelling a long distance but I'd think there would be a limit to how long they'd survive without a plant.

BenT -- They have now been found in Ventura County (where I live), Kern County, and now Tulare County . . . So they are spreading. It does not appear that anything in our climate makes them die on their own.

According to a recent RRD map, I believe it was updated in 2018; there were no reports of RRD in Nevada, Arizona, Oregon, Washington State, Utah, and a few other states. There is another thread on the topic from last week. I was curious about the transportation of the mites, and what is different about these states that has resulted in no RRD.

Las Vegas is the driest state in the country, and we have spider mites galore mid-Summer, Ben. I thought they preferred a drier climate...

The blasted scourge will probably be everywhere in the U.S. in a matter of time. Why are they unable to find something that will wipe out the little *#*! (insert expletive)

Spider mites are good. Or at least they were. Back when Allington, Staplin and Viehmeyer did their first paper, they had trouble keeping the (then presumed) vector mites alive in isolation chambers, because if spider mites got in, they devoured the eriophyids.

Erasmus. If I recall correctly, they sent up ballons with catchment nets. I know there are plastic screen with screen spaces of five microns (as well as larger), then the ballons come down and grad students go to their microscopes. The mites are almost unbelievably primitive. I think of them as a bunch of binary decisions:

land some where Rose? Yes stay

no move to be depositied somewhere else. That's about it.

We know that they must have a high mortality. But their reproductive cycle is hellish simple. How does something die of lack of water if there's no respiration through 'skin'?

How much do they eat? Moisture in the clouds?

They respire through their "shell"

Yes, I remember the "Weeks fiasco" thread too, Jerijen. It is beyond concerning, on another level... It is one thing to be organically floating in the clouds; it is another thing to introduce the da*ned things to CA crops!

Looking at the availability of roses in LV, one would think that people were not too interested in growing them. I returned Sunday evening and checked the big box stores (two) to see if the great roses popping up in other places are here. Basically, there are 5-6 varieties of roses, and that was it. I have not gone to Star Nursery yet to see what their supply looks like (they always have a decent selection). I am ALWAYS on the look-out for RRD.

At some point, if things remain the same, rose lovers will not be able to avoid this scourge... Anger... Agreed!

Ann, Hey there, glad to see you are still here! I've been sort of watching the Knockout roses around town with their rosette, and am still suspicious that adding some boron would make it all go away. I've had it at my place on a plant or two, chop em to ground and it doesn't come back. I've been sprinkling a little borax around my garden every winter for at least 8 years. All these southern clays are low in boron, and when you improve them by upping the pH and organic matter, that's just a recipe for boron deficiency symptoms. Sure there's a virus and a mite, but boron deficiency causes poor calcium uptake, and without calcium, plants can't defend themselves against viruses. Donna

Hey, if you guys wanna play with borax, be careful! Usual recommendation for borax is 11 lbs per acre. Too much and your plants keel over. I sprinkle it like fairy dust.

I believe it about the mites because even tiny orchid seeds get blown all the way into the FL Everglades from Africa with strong hurricane winds.