On Oct 20, 2006, ceejaytown from The Woodlands, TX (Zone 9a) wrote:
Larger canna leaf rollers can defoliate cannas. The larva cuts two strips from the margin of the leaf to the middle rib to form a leaf flap . It then fastens the flap to the leaf with silken threads, and uses this flap as a shelter. Unlike the lesser canna leaf roller which lives within the entire rolled up leaf and defecates in its nest, the larger canna leaf roller keeps its nest clean by flicking away frass, which accumulates on the ground below. In its final instar (the fifth) it empties its gut of leaf material in preparation for pupation. After spinning a silken mat on the floor of its shelter, it pupates within a chrysalis that has a black spine at the anterior end and a long filament that encloses the proboscis of the adult - the Brazilian Skipper.
On Jan 23, 2007, TexasPuddyPrint from Edinburg, TX wrote:
A nice sized skipper. Their larval host is the canna and the caterpillars can defoliate the plants...but I can't complain...I planted the cannas just for these buggers. Love the skippers and they are a nice addition to my butterfly garden.
On Sep 4, 2007, debnes_dfw_tx from Fort Worth, TX (Zone 8a) wrote:
I was delighted to find the Brazilian Skipper chrysalids on my daughters cannas. I carefully cut the leaves they were rolled in to bring home and observe their eclosing. When I unrolled the leaf to look at the chrysalis there was a bit of protest in the form of rapid vibrations inside the leaf. They are so lively with so much personality.
I will be planting cannas next year just for them. I will plant them in the back yard because I expect they will show signs of being eaten, if not be completely defoliated. They are so worth it, a real cinderella story.
I've been battling this insect for well over 8 years now. Prior to that, my Wyoming Cannas hit 15' tall. Since the infestation, I'm lucky to get them up to 8' tall. If I miss even one year of treatment, they rapidly expand in numbers and shred every canna on the farm. Which is a significant number considering I probably have 1/4 acre total of them.
Bayer systemic is not effective for control (Icopronid I think is how the active ingredient is spelled) and since I'm more of a 'limit the chemical use/pollution' type gardner and that particular systemic is indicative in the Bee colony collapse disorder - I don't recommend it for much more than Cucurbita crops.
A touch of Sevin mixed with Dove hand washing detergent seems the most effective - I tried this in '07 and had a significant decline in the insects. This year, I'm testing the idea of just using Dove through the month of June this year. I'll tell you all how it goes..
On Jun 26, 2012, vossner from Richmond, TX (Zone 9a) wrote:
...leaning to negative. I have put a lot of thought and effort towards creating a friendly butterfly habitat and do not mind the shredded look of cat-ravaged plants. But the canna is different--it seems to take longer to recover and therefore, if it is in a visible area, it's gonna be an ugly sight. I may either transplant the cannas to a less visible area or set up a "do not touch this canna" sign. Think they might heed the sign???