Rust diseases

Well, seems quite a bit of discussion on Rust and Terry kindly asked we move the discussion...so.

Like powdery mildew there are hundreds of species of rust. Also like mildew almost all rust species are host specific such as apple cedar rust (alternates between juniper and apple), Cedar quince rust, etc. When I get into work tomorrow I'll take a look in my disease book (Johnson and Lyon) and try to determine the number of species of rust. One of the most devastating rusts is the pine blister rust which in the past decimated white pines. When it was discovered that the alternate host was black currant (ribes spp.) the currant became illegal to grow and were destroyed. Now a new cultivar that is rust resistant has been propagated and are making a comeback (in some states)

It floors me when a customer calls and wants to know why their hawthorn is orange. They're not usually happy when I tell them it's because they planted the alternate host juniper under the tree, OOPS!

Customer-
hands on hips and staring blankly at bogman while tapping foot and acting annoyed...
but sir... tell me now exactly why I can't keep that Juniper. Everybody else gets to have one so why can't I? Rust, what's rust? Isn't that what your car gets when it gets old??? Somewhat reminiscent of Willy Wonka and The Chocolate Factory where Veroqua says, "Daddy I wont an oompa loompa and I wont one noooooooooooooow!"

All joking aside, I have the black ribes currant from Oikos that is allegedly rust resistant. What do you know about this? I wanted black currant real bad and if I have to rip it out I will in a heart beat.

Will counting the number of rusts in a Johnson's and Lyons be like counting sheep before we go to sleep? There are about 5,000 species of rusts in over 100 different genre. Now this of course is if you don't add in smuts. There are about 1200 species of smuts in about 50 genre. All are parasitic on plants and most cause damage to crops. Oh how I love to hate fungi sometimes. Matter of fact, everytime I have to go on a search and destroy mission to try to find out what's spreading what to my Hawthorns I want to scream!

Some basics-
http://www.forestpathology.org/
not nearly as comprehensive as the J & L but sort of ok. I have wanted to order a J & L for a few years but have been too cheap to break down and do it.

Uredinales & Ustilaginales, Ustilaginales & Uredinales, oh my!

Nightie night to you bogman. Sleep tight and don't let the bed bugs bite!

Oh, E!

Always beating me to the punch. I started to read the Lyons book about rusts, but it's soooooo dry. I counted in excess of 150 species on just a few of the pages I did read. Unless you're a botanist or a Tree/shrub care manager the disease and insect books by Lyons are just too much for (even the botanist!) anyone.

I will have to tuck my tail and say that it is the same species of rust that attacks oats/buckthorn and lawns. I was VERY surprised to read that, although the disease doesn't do near as much damage to lawns as it does to oats.

Then again that's why I like some of these discussions. They cause me to research the item and I usually end up learning something, and I did learn!

Oh dear, that nasty J & L book of yours put your tail between your legs for a moment or two! Bad bad bad J & L book... send it to me and I'll punish it for you and banish it to a shelf over here at my house for a few months.

Oh, speaking of tails between the legs...mine is going to be there real soon too. Evidently my husband knew about the buckthorn/lawn/rust connection. I have no idea where he picked that up but "Mr. justgivemethebill and do your thing in the yard" who has little or no interest in plants at all other than to humor me came up with that on his own. Here's where it gets better, I read about my husband being the source here at DG. Appears he had a side conversation with one of my Wild Ones buddies and I didn't even know they were discussing rust. Now I guess I'll have to ask him where he got his information. It wasn't the J & L book though as he picked it up once and set it down almost as fast as he picked it up. He took one look inside and instantaneously commented that he couldn't believe plant people actually read that stuff and liked it. The man has absolutely no taste in reading material so I told him to stick to his Uncle John's Plunges into whatever Bathroom Readers books.

The previous owners of this property intentionally planted apple and crabapple trees AND cedars, so we get to experience the gooey orange globs every year. (The number of galls has reduced since we removed the most productive apple tree, which threw off a couple hundreds pounds of mealy, scabby apples that I picked up and composted until I decided enough was enough.)

I don't know if these people planted the apples and cedars at the same time, or if they consulted a nursery center when they chose these plants...but then again, I'm not sure that most nursery centers would point out the potential danger of planting these two species within 200 feet of each other.

(The name and cause of the cedar-apple rust *was* something I learned in my Master Gardener class, so maybe that $50 wasn't a total waste ;o)

BTW, Garden Terms is a great place to list the most common plant diseases along with pictures and information on causes and treatment.

Gymnosporangium juniperi-virginianae