Check Anniegolden's thread "Under attack, it seems" about halfway down the front page -- there are photos and descriptions that should help.

Nate

Nate, thank you for the link. I will test the leaves with a tissue paper - keeping my fingers crossed.

Natalie, If you haven't already done so, please check the AHS Website ( see the Dictionary under leaf streak and rust.Link to rust below.) They do look similar - both make the foliage very unsightly. The ONLY fungicide I've found to really work here for leaf streak is Cleary 3336. I tried some other fungicides this spring as I was out of the Cleary and should have known better, as most of the other fungicides are ineffective against leaf streak. I now have the Cleary on order from Southern States and hope to get the garden sprayed with it soon! Different fungicides work on rust- usually rotating systemic with contact. There are some good threads on it in this forum. The best way that I can determine leaf streak here is that it usually goes after the center of the leaves first.

Here is a link that might be useful: Daylily Rust AHS Website

This is a stupid question, but does rust *always* pass the "tissue test" (wipes off orange)?

The climate in our area is usually not favorable for rust, so I don't (unmistakeably) see it often. I got slammed with it for sure in 2006, but since then - even though I keep a couple of rust buckets as a barometer - there has been nothing in my garden that I could swear for certain was rust. (I don't and won't spray fungicides, but I don't want to get into that right now.)

We had some rainy weather a week or so ago, and it was warm enough that I was thinking that maybe the conditions were right for rust to show. Some of the daylilies were looking sketchy (though not my barometer rust buckets). I would have said that maybe it was rust and not leaf streak (I'm familiar enough with leaf streak, sigh), as these cultivars looked a little bit "spotty" (they had a few yellowish or light green spots on the leaf surface) with orange areas underneath the leaf - but they failed the tissue test.

I gather there are OTHER daylily diseases out there that affect the foliage besides leaf streak and rust (this from some images on the daylilyrust.org site). So if I have spotty looking plants, with orange underneath, yet they fail the tissue test - does this mean for sure that it isn't rust? Or does rust sometimes fail the test?

Right now my daylilies are not only showing the beginning of leaf streak, but there is some foliage that has been "nipped" by recent frost. There is also some damage from drought stress! Foliage can also get "heat scald" which is caused by excessive heat. A few years ago, we had a very mild May, then around June 1, we had a heat wave with numerous days in the upper 90's. Foliage got absolutely burned up. I remember a garden on tour that year where the host had spent hours cutting back the bad foliage. Regrettably, when foliage suffers damage from heat or drought there is nothing much you can do about it but water like crazy! Chemicals don't help a bit.

On the rust question,I have seen rust - early when it is sort of "inside" the leaf ( some of my friends in the deep South refer to it like this) that you won't get anything on a tissue. It has to come to the surface of the foliage before you get the residue on the tissue.

Thanks, floota; I'll keep an eye on things over the next couple of weeks.

Floota, good link - thank you! I am learning a lot of good stuff.

The tissue test only indicates when the rust is active and producing summer spores; which are rusty orange colored. The rust is active during cool, damp periods; usually spring and late fall. When inactive, or during cold periods, the rust does not produce the orange spores. It either does not produce spores, or it produces winter spores that are dark colored. However, the dark colored spores do not infect daylilies. They infect an alternate host plant, Patrinia, which will allow the rust to over-winter in cold areas. So don't grow daylilies and Patrinia in close proximity. Preferably, don't grow Patrinia at all!
Ed

A few more leaf streak questions. When a plant has leaf streak, do you experts out there remove the ugly foliage? Is it imperative to spray for leaf streak? Is it important to avoid contact with the streaky leaves to prevent spreading the leaf streak to other plants? Thank you.
Christine

Well, I checked my incoming daylilies today (which are soaking in tubs in the shade) and discovered rust on one of them. It was undoubtedly rust, as there were orange spots, some of which passed the "tissue test". :/

Interestingly enough (remember, I have only seen it here for sure once or twice before, back in 2006 and the same or maybe the next year on an incoming plant), the raised pustules were on the *top* side of the leaves, not on the bottom (though there were orange spots on both sides). When I tried the "tissue test" it passed on top, but not on the bottom. It seems that *raised* pustules are the key for that diagnostic.

Nothing else thus far, even plants in the same tub as that infected plant (including a plant shipped in the same box), is showing those raised pustules. (Yet.)

It is funny... when I first got hit with rust I felt like I was gut-punched, and (after a massive culling and cutting foliage on the survivors) could barely bring myself to go out into the garden for a long time. (I even contemplated giving up daylilies.)

Today I just looked at that plant with mild dismay: "Oh boy, rust?" *scrounges tissue, wipes bottom (no), looks closely for raised pustule, finds on top, wipes top (yes)* "Sigh. Out it goes, and begin the Rust Watch!"

Or in other words, the discovery didn't have nearly the impact it did that first time. I probably won't grieve if some of the incoming and/or soaking plants do start breaking out; it will give me a chance to cull the susceptible.

(FWIW, the rusty plant came from the south (a "gift"), and was WINGS OF ANGELS. Out in the trash it went.)

(This is the 3rd time I'm trying to make this response...)

Christine, I'm sorry if I've been hijacking your thread, but you DID say rust, LOL.

Re leaf streak, I just pull the affected leaves, and then try not to touch anything else until I wash my hands or (more likely) change my gloves. (I have sensitivities so I mostly garden wearing disposable vinyl gloves.) I do not spray.

If a plant here is really susceptible to leaf streak then (just as with the rusty plants) it gets tossed. SHIMMERING ELEGANCE got tossed last year for leaf streak (it also has opening issues here). Right now I am looking at two streaky plants with jaundiced eyes. (One of them I will probably suffer with as it is a tet polymerous plant with a reasonably decent flower - and such are still relatively rare. I am using it for hybridizing, but only against plants with decent foliage.)

Life is problematic enough as it is. There are enough beautiful daylilies with healthier foliage that (barring rare genes for hybridizing) there is little reason to tolerate sickly plants. Imho.

Well, I posted too soon. The plant in the tub next to the rust bucket (which was coincidentally - or perhaps not - the other plant sent in that box) also had a few (far fewer) rust pustules. I didn't see them at first; I had to look closely for them. (I went back and looked after my last postings.)

The first plant (the first one discovered with rust today) arrived with nice green foliage. The second plant (just now discovered rusty) arrived largely yellow. I wondered if someone had bleached it or something prior to shipping.

I'm not happy about this, especially as I had hybridizing plans for that second plant. But better to find it out now rather than later...

I have a question. In the future, should I rightly be suspicious if a plant arrives all yellow? Should I be suspecting rust? (Especially if it comes from points south?)

Polymerous, thank you for your response. It was both informative and philosophical, both much appreciated.
Christine

I don't think a yellowed plant is any kind of warning sign for rust. It might have been out of the ground longer than others, or it might have a genetic tendency to yellowing.

But I do think that if you had any plants in the order with visible rust spores, you should consider the entire box likely to be infected (they just won't show it for a while).

Someone else might be better than me for advice on trying to clean the new plants (there are methods), but I would expect that most or all will start showing rust within the next few weeks without treatment.

The good news is if you're hybridizing, a rust outbreak will give you some good information on the resistance of the plants you own. The bad news is that you'll have a hard time getting rid of it in the garden without chemical fungicides.

But I do think that if you grow daylilies in the south, it's not a matter of "if" but "when" you see rust.

At this point in time, I think growing daylilies in the south pretty much requires either some level of rust tolerance or some level of rust treatment.

Nate

I really recommend anyone receiving daylilies go through a pretty simple procedure to try to ensure that rust is not introduced to their gardens. The rust dwells in the green foliage and when it "blooms" it produces the orange spores that can live (like seeds) outside the foliage for a length of time. When you receive the plant, go to an area that is used only for receiving the plants. Strip the outer two leaves on each side of each fan down to the crown. Cut off all remaining green foliage down to the white, but not into the crown. Bag and dispose of all boxes, packing and foliage into a sealed bag and into the garbage. Mix a bleach solution at 5% concentration; generous 3/4 cup of bleach per gallon water. Soak the plants for 30 minutes to and hour, rinse well and then they are ready to plant. This will kill any spores hiding on the plant. Rotate the plant in the soak to be sure everything is covered. Disinfect the scissors you used to trim the foliage and any other thing that might harbor a stray spore. Change clothes, wash up and now you're ready to plant. The plant will start new foliage from the center of the fan that is free of rust. For those of us in hardiness zones greater than 7, it is also wise to keep a quarantine area for these new plants, just to be sure.
Good luck, Ed

Nate, thanks for your comment about yellowing.

Although I am not in the deep South (I live in northern CA), from my understanding of everything that I have read, once we have rust, there is no getting rid of it. We will *always* have rust because 1) it does not get cold enough here to winter kill and 2) fungicides only surpress the rust, they don't eliminate it. So that ship sailed years ago.

I do have to wonder, though. When I got hit by the rust back in 2006, I tossed out all but a few rust factories (CAMEROONS and GREEN DOLPHIN STREET, which were both heavily affected) and cut down all the foliage on everything, and sprayed with a solution of Dawn (recommended by a club member who gardens organically and also eschews fungicides). I haven't seen rust since on those two barometer plants (you'd think it would show up there, if anywhere) so I don't know if I indeed "got rid of it" (hard to believe given how bad the garden was at that state) or if our climate has been suppressing it.

(Going off on a tangent here, I have to wonder about dormant plants. In Zone 6 and above, if you had a garden of only dormant daylilies, and had no ourside source of incoming spores (yeah, very theoretical, I know!) would you lose the rust once everything went winter dormant? Even in warm areas with a lack of killing frost? Just how long do those orange spores persist without foliage?)

Ed, thanks for the information re treatment for incoming daylilies... (Patrick Stamile's recommendation years ago, iirc). I always had to wonder if the recommendation is based on hope that only the outer leaves are infected (not all the way down into the white), and the rest of the plant is clean. So for some plants that might work (early stages of infection), and others not. (Which is why I guess you would quarantine.)

At this point, with the cat out of the bag, I'm not sure if it would do any good to go through that whole procedure, but I'll consider it. (Ugh. I'm only trying to get my veggie garden in before we get rain later this week...)

I am trying to be philosophical about all of this. I *did* have big hybridizing plans for that one plant, but better to know now that it is rust prone. (Re any other plants... does anyone know if blooms, pollen, or seeds get infected? *hope springs eternal*)

Yes, my recommendation for treating incoming plants is based on Pat Stamile's procedure. I hope I didn't leave anything important out.
I've heard the statement; "once we have rust, there is no getting rid of it. We will *always* have rust because 1) it does not get cold enough here to winter kill and 2) fungicides only surpress the rust, they don't eliminate it", and I have to take issue with it.
If you are in a warm area, then it's harder to get rid of rust, because you have to be forever on guard and use procedures to prevent infection. There are lots of things that you can do to help prevent rust getting into your gardens, like the incoming plants procedure above. There are things that you can do to help prevent rust in your garden from spreading. Good gardening hygiene! Make sure each plant has good air circulation around the clump. Don't water late at night.
Rust, in my opinion moves slowly from one clump to the next. Sometimes skipping resistant plants to find the susceptible. Without the winter kill, you must find the spore-in-the-haystack and kill it before it gets to your susceptible plant and conditions favor its sporulation (germination). Having a garden full of dormants would certainly give you a leg-up in the battle, but it will also give you more rust susceptible plants (in my opinion). Dormants haven't needed to evolve rust resistance like evergreens, and they are most often hybridized in the north, where rust resistance is not selected for. So it's kind of a trade-off in my mind, certainly not the solution.
It's also true that most fungicides we use for rust are developed for food-crops, which are annuals. So the prescribed use is only to control the rust until harvest, after which the plants and rust are destroyed. It has been shown in many of the research papers which fungicides are effective killing the mycellium inside the leaf and the spores outside the leaf. Some fungicides list mixture rates to prevent, and to eradicate the fungus. It is difficult, I agree, but not impossible to eliminate the fungus once you have it. Kind of like nut grass, it's doable but it takes lots of effort, and probably a little luck. And make sure the fungicides you are using are actually effective against daylily rust. If you are against using fungicides, there are alternatives. But it takes even more determination to develop your plan and then stick to it.
About using rusty plants for hybridizing. I have several hybridizing lines, and in each I have resistant plants. All new arrivals are crossed to a resistant plant. I try never to cross susceptible to susceptible (well almost!). Some plants consistently give me highly resistant offspring. I have several plants that in two generations give me a very resistant plant from a very susceptible parent. So I don't throw them away immediately, but when they don't have traits I feel I need. Out they go!
Good luck, Ed

Thanks for your comments, Ed. I appeciate them.

I'm unsure about being able to kill off the rust or not (in warm weather areas). Just about everything that I have read says that you only suppress it, yet my garden seems to have been clean (at least, no visible pustules) since that initial exposure, so I don't know what to make of it. (Not, mind you, that I have minutely scrutinized every leaf on every plant - though I do check the remaining previously very rusty plants periodically.) I "got it all in time"? (Sounds like cancer, lol - and doesn't explain why those non-dormant rusty plants haven't been rusty since.) Climate not conducive? (Which seems to be the case, but still...)

Re dormants... you make a good point in that northern gardens don't necessarily have to worry about rust resistance (especially those hybridizing mainly for other northern gardens). I was just curious as to whether - in zones 8 and 9 - if one DID have a garden of all dormants, if they got infected, would the plants all come up clean next year (provided all the dead leaves were removed). I guess we may never know.

Re hybridizing - only two generations to get a very resistant plant? Depending on how many genes control resistance, the genetics of the parent plants and how many F2 seedlings you grew out, I can see that happening. (Only takes four years minimum to get there, sigh - and that's IF your environment is such that you can reliably tell which seedlings are susceptible or not.)

(DH asked me something to that point - why not cross the rusty purchased plant to a resistant plant, etc. etc. Well, there are a lot of excuses (er, reasons) as to why not, including not much sunny, deer-proof, unlandscaped space that I can use for seedlings. Since I have WAY more crosses that I want to make than I ever have the time/energy/space to grow out, and since I also don't want to perpetually be battling rust, it seemed the best thing to just toss the rust bucket(s).)

Ed, do you mind if I ask how many F2 seedlings you had to grow out to get at least one resistant plant? I would guess at least 16 for tets - with no guarantee that you would get a very resistant plant because the probabilities hold for large populations, not necessarily for small ones (though you could get one to a few moderately resistant plants, depending on the genetics of the parents).

(My reasoning is as follows... We don't know how many genes are involved, but for tets, making some very simplistic (and possibly incorrect) assumptions (only one gene determines resistance, an additive as opposed to dominant/recessive mechanism (what I gather seems to be the case?), the pod parent's extra DNA does not affect resistance, the resistant parent is rrrr and the susceptible parent is RRRR - so this assumes the best and worst case plants), I would guess you would get in the first generation F1 all rrRR (call that average resistance/susceptibility), and in the second generation F2:

1 rrrr very resistant F2 plant
4 rrrR equivalent moderately resistant plants
6 rrRR equivalent average resistance/susceptibility plants
4 rRRR equivalent moderately susceptible plants
1 RRRR very susceptible plants

If the resistant parent is rrrR and/or the susceptible parent is RRRr then the picture gets more complicated.)

I wish there was more information available in one location as to resistant cultivars. (Yes, I have been reading daylilyrust.org, forums, and hybridizer's comments.) I have gathered some of the reputedly resistant plants together, but for other plants (with traits that I want) it is hard to tell. (If anyone can tell me one way or the other re resistance on WHITE MOUNTAIN or ARCTIC LACE I would appreciate it!)

I am also interested in the "numbers game" of this, since I'm going to be trying to select seedlings for rust resistance too.

Right now I'm having enough trouble just finding tet parents that are resistant. FIRE AGATE is the only really strong one I've found out of the plants I feel I've had adequate time to observe. It is planted in the seedling bed, and I haven't sprayed anything in that bed in over a year. Most of the seedlings have a fair amount of rust, but FIRE AGATE has not shown any yet.

Nate

I'm sorry to say, I can only speculate on the numbers of F2 seedlings to get a resistant seedling from a resistant X susceptible cross. I do usually make small exploratory (around 12 seedlings) crosses and then use the information I get to make further long crosses. Since I don't only select for rust resistance, I really don't know if your results will follow Mendelian predictions. My gut feeling is that the highest rust resistance comes from multiple genes, instead of a single gene, and I think that's good, because it is harder for the rust to mutate and overcome multiple gene resistance. Other hybridizer friends say it's possible to get a high resistant plant from two susceptibles, and I don't disagree. However, my highly resistant plants consistently give me high resistance seedlings.

Yes, FIRE AGATE does have high resistance. I'm breeding for flat, round, ruffled forms and would be happy to tell you what I'm using for a particular color or pattern as an anchor plant. I'm afraid I don't know for sure of any near white tet that has good rust resistance. I have heard LITTLE INFANT does, but have never grown it. I don't grow WHITE MOUNTAIN or ARCTIC LACE, but I see GREAT WHITE, ADMIRAL'S BRAID and LAKE EFFECT in the backgrounds, and will predict they both will be on the rusty side. Purples and lavenders often throw whites, so I think I would take those whites and cross them to BELA LUGOSI or COSMIC SENSATION, which both have above avg rust resistance. If you do enough, you should get something on the white side, especially in the F2.
Good luck, Ed

Interestingly LAKE EFFECT also has a high propensity for leaf streak. Wouldn't it be interesting if we had a study to test the correlation between those cultivars that have low tolerance for leaf streak and high susceptibility to rust?
BTW, my order for Cleary 3336 just arrived today from GA. Couldn't find it anywhere in the state of Va. It is the only fungicide ( other than Systhane) that is effective in treating leaf streak. I tried various other fungicides and nothing has had much effect. Will be spraying it tomorrow although it's a little late.

Some people also use Cleary 3336 for rust. I have never bought any on advice of others, but would be interested in any opinion on any effect it has on rust. My intuition tells me that rust susceptibility and leaf streak susceptibility go hand in hand. Ed

Floota - I had wondered about that myself (correlation between leaf streak and rust susceptibility).

Ed and Nate, thanks for your comments on FIRE AGATE. I don't have any tet doubles, though I do wonder if the sometimes doubling of BUT WAIT THERE'S MORE could be stabilized by crossing it to a double. In that vein, FIRE AGATE (apart from its short height) looks like it might be a good candidate for a potential cross.

Ed, it sounds like it would be a good thing for us if multiple genes were involved in rust resistance, and it is interesting that some hybridizers can get resistant plants from two susceptible parents. Unless I absolutely have to I would prefer not to cross two susceptible plants, though.

My hybridizing goals I'm afraid aren't narrowly focused. However, in priority, and in terms of "faces" (as opposed to plant habit) I am interested in:

1. Tet polymerous plants (I am working with several but it is a hard row to hoe, which is why I like to make other crosses, just to have some relative success to encourage me to keep going)
2. Tet near-whites (which is why my interest in WHITE MOUNTAIN and ARCTIC LACE; I have several other tet near-whites, but at least one of those I have to suspect rustiness in due to its parentage)
3. Lavenders (which are on the blue side)
4. Melons and/or oranges
and currently also
5. (a plant habit and not a "face") "instant rebloom" (thanks in part to a seedling of mine)

I have a small number of parents which are reportedly rust resistant to work with, mostly in near-white or pastels. My plan was to cross some of those against ARCTIC LACE and WHITE MOUNTAIN and to see what ensues. (How I am going to evalute rust resistance short of importing another rust bucket, is another question.)

FIRE AGATE is an interesting plant. It's registered at 80% double, but only 1/4 of its lineage is from doubles (KEATS line). On the Floyd Cove website, Pat Stamile also comments that HEARTS OF FIRE (another grandparent) was making doubles when crossed with other singles, even though HEARTS OF FIRE has no doubles in its background. So I think FIRE AGATE could contribute to either single or double lines.

Here are my personal observations, mostly from last year because it hasn't bloomed yet this year:
-Bright red self that glows in sunlight.
-Tends to melt on hot days
-Not always double, but the single blooms are pretty good too
-Very rust resistant
-Heavy foliage that has some rippling instead of the standard soft arch.

Nate

Ed, it sounds like it would be a good thing for us if multiple genes were involved in rust resistance, and it is interesting that some hybridizers can get resistant plants from two susceptible parents. Unless I absolutely have to I would prefer not to cross two susceptible plants, though.

Crossing two susceptibles giving a resistant is a claim that I won't dispute, but I can't validate it either. I think you will get much better results using at least one resistant plant in the cross.

I can't help you with poly's. With whites, you might look for plants out of tetra JOAN SENIOR. She is very resistant as a dip, and converted, I would expect even more so. I gave you purples earlier. I come up blank on a lavender, but Stamile's MAGENTA MAGIC will probably throw some when crossed to a white. As a base for melons and oranges, you might use AMERICAN FREEDOM. Stamile's OLYMPIC SHOWCASE is a nice gold, crossed to a red will give you some bright oranges.
Hope this helps, Ed

Nate, thanks for the information on FIRE AGATE. (Could you explain the bit about "rippling" foliage, please? I know what arching foliage is, and (sadly) I know what upright foliage is, too - but I have never heard of rippling.)

Ed, thanks as always for your comments. I have enough poly parents to be working with, so a variety of parents is not the issue there.

I did have AMERICAN FREEDOM at one time, but for whatever reason it died (or got eaten... the garden has been through some hard times the past few years). I did have some seedlings from it, but I ended up discarding them due to various problems.

I will take a look at MAGENTA MAGIC, and will start looking for plants with tet JOAN SENIOR in the background.

Rippling was the best word I could come up with, but perhaps a picture is better.

{{gwi:689570}}

Nate