Tuesday, September 21, 2010

Welcome Home...

We returned from a 10 day vacation to a horrible sight. Our beautiful Cannas, which are pretty much the center piece of the landscape, had been totally munched by worms. In addition, our Hackberry tree (an Ike survivor that in many ways I wish had perished) was loaded with aphids. The infestation was so bad that the stairs and virtually all other surface areas were sticky with honeydew. Not a great welcome home…

 There’s not really much I could have done about the aphid attack. Aphids are somewhat migratory and prey on stressed plants. And let’s face it - this August was VERY stressful. Short of spraying the tree, which is not practical or particularly eco-friendly, there were no control/management tactics I could’ve used. The Cannas, on the other hand, are a different story. Had I been on the ball there’s a good chance that I could have limited the damage.

Technically these “worms” are Canna Leaf Rollers and there are actually 2 different types common to the area. The Galveston County Extension website has an excellent write up on these critters CLICK HERE if you want more details. They also present a variety of control/management strategies that can be effective.

This might be the appropriate time for me to describe my overall “philosophy” on pest management. Generally speaking I’m not a big fan of chemical pest control. It’s not that I’m some kind of green, organic, tree hugging, eco-nut - it’s that I’m LAZY. It takes a lot of effort to mix up and apply chemical pesticides and more often than not, they have to be re-applied - more work. Nope, I have more of a survival of the fittest approach. If a plant has repeated issues with a pest(s) and can’t survive on its own, then it probably doesn’t belong in my landscape. I might also add that I’ve worked around pesticides my entire career and I’m aware of the potential health risks associated with long-term exposure. Plus - I don’t like storing these materials around the house. Some of my fellow gardening friends have what amounts to a toxic waste dump in their garage. I shutter to think about the volume of pesticides that contaminated our waters as the result of Ike flooding. That being said - I’m not above spraying if and when necessary. Especially if I can use a material that is low in toxicity or has no chemical toxicity.

Bacillus thuringiensis (Bt) is a bio-control product that is particularly effective on worms and caterpillars. Because it is formulated from a bacterium it is considered extremely eco-friendly. Bt is marketed under a variety of different names but Dipel seems to be the most readily available. Applied as a liquid, leaves should be thoroughly sprayed (especially the undersides) when you see the first signs of munching. Be prepared to re-apply 2-3 times for optimum control.

Spraying plants “before” you have a serious problem is the easy part of this plan. The real issue is what to do about plants that have already been damaged? I cut mine back - severely. Then meticulously cleaned up all the dead leaves and decaying foliage under the plants. That’s where the immatures like to hangout. Then I sprayed the remaining foliage with Bt. I also applied some fertilizer to help get the new growth kicked in to high gear.

Of course there’s a huge hole in the landscape but I guess that’s better than having a bunch of totally munched up plants standing out like a sore thumb. I will keep yall posted on the progress of this pest management project.