Aster Yellows

[digitS']

I just thought I'd post a picture of what is probably Aster Yellows:

The stem of this snapdragon is flat. The flowers will never open. Aster Yellows is a Disease spread by a Pest.

Here are some more pictures and information on this disease:

Colorado State University - with a picture of the disease in Cosmos.

Michigan State University - with a picture of the disease in Statice.

Oregon State University - with a picture of the disease in Carrots.

The disease shows up now & then in my garden but also outside the garden. One of the plants that most commonly shows signs of Aster Yellows is the dandelion!

Steve

 

[Carol Dee]

WOW, look at that flower bed! I would always have fresh flowers in the house I hope you can stop it before it infects others Good Luck.

 

[digitS']

Infection is kind of random, Carol Dee.

Leaf hoppers spread this stuff and one of those university fact sheets say that over 300 species of plants are vulnerable. Since it is a phytoplasm bacterial infection and that's one of the causes of witch's broom in trees, I wonder if there aren't even more that fall victim to this crud. It also shows up sometimes in my squash :/.

And, it's all the leaf hopper's fault!

I don't know how my cutting garden can dodge this pest since the adults and their spittlebug larvae are so common in alfalfa. There are acres of alfalfa on either side of this garden.

Steve

 

[thistlebloom]

I don't know how my cutting garden can dodge this pest since the adults and their spittlebug larvae are so common in alfalfa. There are acres of alfalfa on either side of this garden.

Steve

So spittlebugs are leafhopper larvae?
We have so many spittlebugs every spring and they are really starting to bug me. I hose the buggers off, but I think all I'm really doing is hosing their foam away and they are left clinging to the plant ready to make more foamy yuk. I was told by someone who should know, that they are harmless and don't bother plants, but I don't believe her, I notice the plants with the sb have deformed leaves.
I wonder if I hit them with a little horticultural oil early on if that would kill them....
They are also all over the pines, and the knapweed along the roadside.

 

[NwMtGardener]

I dunno much about pests, but i wouldnt call spittlebugs harmless! They almost suck the life outta my bee balm every year, little buggers! I really twist and turn my plants around to find them and hit them with the insecticidal soap. I have seen some around after this procedure, maybe it didnt really kill them all, or more moved in!! It helped tho.

 

[lesa]

Hmm, I always assumed they were harmless...Great another enemy!!

 

[digitS']

They are pretty well defended against contact sprays.

I have wondered if washing the spittle off makes them vulnerable to predators. It is likely worth tormenting them with the hose just out of spitefulness .

Maybe hitting them with soap would work before they can get the spittle up again, too.

Steve

 

[sassycat]

This is a case of Fasciation. Fasaciation is when you have a random genetic disruption during the growing season. often it is not seen the next year, and cannot be transmitted from plant to plant, because it is not infectious. Fasciation can happen for number of reasons, but it seems like the underlying factor in all cases is a growth hormone change within the plant. This can happen to many plants, including what you are describing on your dandelions. A tell tale sign of fasciation is the flat stem.

 

[digitS']

By golly, I think you are right, Sassycat!

I have just looked at this: Fasciation, Colorado State University

The author talks about disease as a possible cause amongst other causes. However, aster yellows is not mentioned. I have had Black-Eyed Susan flowers just like the one in the photo. A little weird, all of it, wouldn't you say? Fasciation, a word I don't even recognize . . . You know, this doesn't make me dislike leafhoppers any less . . . .

So, Gregor Mendel knew about this? Well, since my natural science classes were limited to a couple of semesters of geography & biology, I guess Mendel is still ahead of me after all these centuries !

Steve