Return to the Name That Plant Forum
| Post a Follow-Up
Canna with bugs
| | |
Posted by sirsedum (My Page) on Mon, Nov 2, 09 at 9:19
| Hello, can everyone confirm or dis confirm that this damage to my Canna was caused by spider mites? |
Image link: Canna with bugs (57 k)
Follow-Up Postings:
RE: Canna with bugs
| | |
| Doesn't look at all like spider mites, to me. |
RE: Canna with bugs
| | |
| Agreed - not spider mites. If I had to guess, I'd say scale, but without knowing what part of the country you're in, it's difficult to pinpoint which pests cannas host. Here in Southern California, for instance, I've never seen this kind of damage on any. |
RE: Canna with bugs
| | |
| Ok, so i sent it to a specialist and he thinks its cold dmg or phytotoxicity. But he was unsure as well. they are kept in a greenhouse and the temperature never drops that dramatically. I as no longer believe it is bugs of any kind. If it is not phytotoxicity then idk. We spray fungicide on a bi weekly basis for preventative measures. I also read something bout a Canna Rust, but was never able to match photos to confirm this idea. If you have had this problem please let me know |
RE: Canna with bugs
| | |
Here is the answer the Specialist gave me, for any of you who might have the same problem. hope this helps someone else too.
"Thanks for sending more images (they were much better). Disregard any comments I made regarding cold injury – I couldn’t distinguish between normal leaf coloration and potential symptoms in the first image you submitted. There are two problems I see in the images you sent. The easiest one to diagnose is Rust as observed in image ‘sick plant 003’. Rust is fairly common on Cannas and most commonly occurs when the leaves are wet (condensation or overhead irrigation/rain) for 3 to 6 hours, under high humidity levels (>80%, and with cool to moderate temperatures (50 to 75° F). Some of the most effect fungicides include Banner Maxx, Daconil, Eagle, and Heritage – all of these are best when applied preventatively or immediately after rust has been observed. The leaf spots in the other images are most likely Alternaria leaf spot which is also fairly common on Canna. I cannot be certain if Alternaria is the pathogen causing the leaf spots or if another fungal pathogen is present. To be certain, send leaf samples to a diagnostic lab for proper identification. Leaf spots also usually occur following periods of wet foliage, high relative humidity, and cool temperatures. Some of the most effective fungicides for controlling leaf spots include Chipco 26GT, Daconil, Heritage, Protect, and Medallion. Again, it is best to use these products preventatively (when conditions are optimal) or immediately after the leaf spots are present." |
Post a Follow-Up
Please Note: Only registered members are able to post messages to this forum. If you are a member, please log in. If you aren't yet a member, join now!
Return to the Name That Plant Forum
|
|
|
