Hosta Virus X epidemic

[Chris_W]

Hi Liselotte,

It isn't that it takes 3 years to show up in testing but 3 years to show it visually. If they had HVX Dr. Lockhart's test should have found it.

We received 2 plants from Darwin Plants last year with HVX: Paradise Joyce and Goldrush, and received Striptease from them in 2003 with HVX! Goldrush was the absolute worst case of HVX I have ever seen. I also received Paradise Joyce from another source and they didn't look right last summer so I had those tested. That test came back negative! I destroyed all of the Paradise Joyce from Darwin Plants and isolated the Paradise Joyce from the batch that tested negative. If random samples of that batch test negative again this year I'll go ahead and give them new potting soil and watch them the rest of the season and probably plant them in the fall.

By the way, last summer I was sounding the alarm to our suppliers in Holland and received personal phone calls from John Van Bourgendien and Jack DeVroomen. They listened and seemed to take it very seriously. Darwin ignored me, just sent a paper credit for Goldrush and I never heard from them again Van Bourgendien never even gave me credit, so they will not be seeing any more of my business

This year we will just have to wait and see. Some of what we are selling now is based on a couple of our suppliers claims that they are testing everything for it, plus we got clean plant stock from them last year so we feel better about selling things from those suppliers. I think this will be the make it or break it year as to whether we continue to buy anything bare root and might have to resort to growing it all from TC...

[Bill Meyer]

Hi Chris,

When it comes to the Dutch wholesalers, I understand that they each buy from a number of different growers. If they buy bare-root, they wouldn't even see the virus. They seem to have been surprised by it over there last summer, but I hear they are taking it very seriously now. I've heard that growers are being inspected and their hostas ordered destroyed and their fields quarantined. There may be quite a bit of infected bare-root stock still in cold storage from last year though.

Once the big box stores start rejecting all those infected plants they bought from American wholesalers this year, I think we'll see everyone starting to take HVX seriously. The money angle is the way to get this thing stopped. The sellers who have moved so many obviously infected plants out to the retailers will be facing some major refunds or replacements. I think they are starting to get the message by now as their customers are seeing more and more infected plants.

Apparently some hostas show HVX symptoms almost immediately while others can take years if they ever do. I've asked Dr. Lockhart if he has a list of those which did not show symptoms in his study after three years. That might tell us something.

It's important that we all be careful handling any plants of the varieties that have been infected for the next few years. If you know they came from a clean source, they should be fine, but ones that may have originated from the infected sources should be handled with care. A negative virus test does not mean a plant is clean. It may just mean that there wasn't any virus present in that leaf. With this disease hiding for such long periods, I think we just have to be careful with any suspect plants.

For those who were hit with hail recently - be especially careful with those leaves. They are leaking sap all over and handling them is a good way to pass it from plant to plant if you have one that is infected.

So, Chris, how about writing an article for American Nurseryman? There are a lot of other nursery owners out there who could really use a heads-up about HVX, and who has more practical experience with it than you?

........Bill Meyer

[Chris_W]

Thanks once again for the info Bill. It sure does help to have someone like yourself taking it as seriously as we all do.

When we tested things last year we sent out 2 to 3 leaves from each plant and with the apparently healthy looking batches we sent out at samples from at least 2 plants. But thanks for the reminder to send more than one leaf. I think I read somewhere to send 3 to 5 of the oldest leaves from the plant for better accuracy.

I just finished writing a radio ad for this weekend so heck, I might as well start writing a magazine article too Seriously, though, that sounds like a good idea. As soon as things quiet down here with our busiest mail order week of the year colliding with the grand opening of the new nursery this week I might actually have time to sleep again too

Keep us posted to any further developments when you get the chance.

Thanks again!

Chris

[Liselotte]

Thank you very much Chris and Bill for the info.
Van Bourgendien and De Vroomen I am familar with, but never heard of Darwin.
I am glad to hear the Dutch are taking the virus seriously.
We still may be better off in Europe, because there is no power washing of Hostas here. You can order potted plants or bare root, but bare root is not washed, there is some soil attached, which to me looks like a light potting mix.

Last year Striptease did develop greening up and looked very strange. Although perhaps it was the change in potting soil and fertilizer ( I went a little overboard). But by the time I could send in the leaves (in October) I only had new leaves looking perfectly healthy. I sent 3 leaves of each kind.
Since my supplier told me last fall, that none of his odd looking plants has tested positive, I have ordered more plants this spring.
I will keep the plants isolated just to make certain and definitely no let any Dutch Hostas leave the garden for the time being.
The reasons I started ordering in Holland (03) was the size (and price). My American TCs generally take 4 years at our altitude to reach a reasonable size and garanties to grow for the customer.
The problem of importing from the US with the Swiss Post office has gone out of hand and only picking up the plants has worked well.
This reminds me, last fall when the IL.Dept.of Agriculture came to inspect the plants and give me the phyto, the inspector had never heard of the virus and promised to look into it!

[Jim Soper]

What do you think? I saw some very bad looking plants at a local hardware store's garden center. One was set aside, I hope they don't go around trimming off the bad leaves.

[Chris_W]

I guess when the virus gets that bad you just hope nobody buys it Do you know what that variety is supposed to be?

That white "burned" look was the same type of coloration that occurred on Goldrush.

[Jim Soper]

Chris,

There were a couple of different varieties, tagged as hosta “assorted”. The damaged on the darker ones looks a lot like the infected ‘Blue Cadet’ I saw at Lowe’s last week.

Here’s another photo. I’ve never had a plant that showed the tan/brown dry scale patches. I don’t know how long it takes for the new leaves to show damage. There really wasn’t any texture difference other than the dry, dead patchy part.

It’s kind of scary to think that an unknowing employee could go out and “do the right thing” by trimming of the bad leaves, and the bad leaves on the ones that didn’t get watered, or got too much sun, or got a little frostbite, and then send home healthy looking plants that were now infected....

[Chris_W]

That looks like Birchwood Parky's Gold, which could explain the "burning" part that was similar on it's sport, Goldrush, which you can see in some of the first pictures on this thread.

By the way, feel free to use any of my pictures to help with a flyer or to share with your customers at the farmers market. That goes for anyone, too, just go ahead and use them if you need in order to show people the effects.

[Jim Soper]

Thanks Chris.

We have a sign and a handout about HVX. I did want to add a couple of photos showing something other than the “sharpie on newsprint” look that I had seen here.

As far as my pictures, anyone is welcome to print, forward, or otherwise use for personal use, show or give to your local nursery, etc. If you wish to republish, please ask. I can’t imagine saying no, but I would like to know where they are when they are published. You might have observed that I put a copyright notice on a couple of them in a previous post -- probably a habit since I used to be a working professional photographer – but also because I was told some of my photos posted here have been taken and republished without asking permission. If anyone does want copies of my photos or needs a larger file for printing just let me know.

We've also changed the wording on our "instruction" sheet we hand out with purchases:

"...Trim damaged leaves and faded flower stalks. When trimming more than one plant tools should be cleaned between plants. The transfer of sap from one plant to another can spread disease, so cleaning tools between cuttings has become essential for disease control...."

Comments for better wording are welcome.


Thanks for the comments. "cleaning" and "essential" are too weak and too much like what everyone has been told (and ignored) before.

Updated wording:

"...Trim damaged leaves and faded flower stalks. When trimming more than one plant tools should be cleaned and disinfected between plants. The transfer of sap from one plant to another can spread disease, so disinfecting tools between cuttings has become essential for disease control."

[Mary Ann]

"Sterilizing" would be a stronger word, Jim.

[newtohosta-no more]

Or maybe the word "sanitizing". Some would consider "cleaning" as just washing off with water, not something like a bleach solution.

[mamaw2]

Update-daughter was at the nursery yesterday where I got my diseased Stiletto earlier this spring. She called to tell me there weren't any Stilettos on the shelf anymore. Guess the results of their testing weren't positive...or in this case negative. Talked to the local extension service this week and they have reports of HVX in St. Louis only, but he did seem knowledgeable about HVX and knew about the ELISA test. That's a good thing.

[newtohosta-no more]

I stopped at a nursery yesterday near my DD's college and asked the lady working there is she was familar with HVX. She really seemed on the ball! She makes sure all the employees know to sanitize their tools between plants and they quarantine their incoming plants from suppliers for a season. She did know that the plants could be virused without showing signs for up to 3-5 yrs. But she was very concerned about her inventory and obviously makes the effort to make sure they sell healthy plants. Naturally I had to buy one.

[Primroselane]

I wrote to both the MDA and Michigan State University and today this article was in their Landscape Alert.

This spring, MDA inspectors found Hosta virus X (HVX) in record high numbers at sales lots in Michigan. Most experts agree that HVX has become quite common in the trade. Plants infected with this disease can exhibit a variety of symptoms, as the disease affects cultivars differently. The most common symptom is mottling of the leaves. Other symptoms can include stunting, twisting and puckering of the leaves. The symptoms may be quite obvious or may be very subtle. As with most viral diseases, some varieties appear to be resistant while others are much more susceptible. The long-term effect of HVX is to weaken the plant, which may eventually lead to death.

Like most plant producers, Hosta growers are always looking for new varieties. Unfortunately, before much was known about HVX, some unusually looking Hosta "sports" were cultivated and later scientists found the cause of the unusual mottling and coloration was HVX. The variety "Breakdance" is reported to be of the 100 percent-infected varieties.

The best way to avoid getting HVX in the garden is to buy quality, disease-free plants. When buying new Hosta watch for unusually mottled plants. Collectors with high value varieties may wish to have their plants tested to make sure they are disease-free. If you do find a plant infected with HVX in your garden it should be removed and destroyed. The disease itself is mechanically transmitted through transfer of infected sap. Therefore, it is a good idea to practice good sanitation in the garden, including sterilizing cutting tools between each plant when you are trimming or dividing Hosta. A wealth of information about HVX can be found on the Internet by searching on the terms: "Hosta Virus X."

Infected plants should be brought to the attention of staff on the sales lot. Also, incidences of infected plants can be reported to the nearest MDA office that serves your county. A listing of MDA contacts can be found on the MDA web site at: www.michigan.gov/mda key word "Regions."

[Chris_W]

Here is a link to pictures they posted as part of the article:

MSU Landscape Alert HVX pictures

My only concern is that it appears they are flagging and pulling plants with visual symptoms when they should be destroying entire batches even if just one plant in a batch shows the signs. They also mention in the article that HVX infection will lead to the death of the plant, but I don't think that has really been shown to be the case.

Still, this is a big step forward to have the Michigan Department of Agriculture acknowledge the huge scope of the problem with this type of bulletin!

One note: That picture of Queen Josephine certainly looks diseased but I'm not sure it is from HVX...

[Primroselane]

This is the web address of M S U if you want to see the article on the Hosta Virus that Mike Bryan from the MDA wrote and the photos.
http://www.ipm.msu.edu/CAT05_land/L05-13-05.htm#2

[buster]

I had a Gold Standard tested by Dr. Lockhart last year and it tested negitive....now it is showing signs of HVX...also have Paul Glory showing siigns

buster

[Chris_W]

Buster, can you post a picture of them? Sometimes frost damage or natural color changes can look similar, especially on those two particular plants. But Gold Standard is pretty definitive once it gets really bad. it will have dark green streaking in the gold portion that mostly follows along the veins.

I do believe it is possible to have a very low concentration come up negative in the initial tests done by Dr. Lockhart. By the end of last summer he was getting flooded with so many samples that I don't think he was doing anything too detailed or elaborate with them.

If you can post a picture we'll take a look for you.

[dannyboy]

I wanted to let you know I was speaking to one of our Dept of Agriculture representatives in Pennsylvania yesterday and I took the opportunity to ask him if he was aware of the Hosta Virus X epidemic. He told me he was not so I relayed everything I had learned from Caliloo and this forum, I also made copies of the info Caliloo had given to me and passed it along. He was very interested and did state he had seen BPGs at a local nursery that matched the symptoms. Hopefully this will help out with controlling the problem.

Elaine

[FreakyCola]

Could you update us on which hostas are known to be infected?