Sunday, August 28, 2011

Oh No, Not the Agave Snout Weevil!

This is all that is left of one of my formerly beautiful Agave Americana's after being infested with what I am sure is the agave snout weevil. I have read about this scourge of low desert gardens before and felt lucky that my agave's until this point had not been affected. Now I am unable to say that.

I noticed on Friday that on of the agaves was looking rather flat and assumed that Tex had trampled it in his constant quest to catch a lizard. However on closer examination I saw that the entire plant had collapsed and I was able to pull out all the leaves leaving only the heart which fell over soon after. As I cleared it all away there was a foul smell which I now know is a classic sign of this pest.

The female weevils chew their way into the heart of the agaves in the spring leaving bacteria as they go. They then lay their eggs which hatch out to produce the next generation of adults. Signs often appear in the infested agave in the summer after the life cycle has been completed and it is actually the bacterial infection that kills the plant which is why the smell is so bad. At this point it is too late to save the plant. The only treatment appears to be application of a strong pesticide in the spring to prevent infestation. There is more great information here about this pest here from the wonderful Desert Botanical Garden.

Although I am really sad to lose such a lovely specimen I absolutely don't want to use any toxic chemicals in my yard and so I will just have to let nature take its course, and be prepared for what may follow. Agave Americana is a particular favorite of mine with it's huge sculptured look but if they are all affected by this I am prepared to avoid planting them in the future. This is the way of gardening sometimes hard though it may be. I am just glad I haven't lost a tree, that would be far worse.

Here are the agave's that are left standing right next to the affected ones.

They seem to be fine right now but their close proximity to the others doesn't give me a great deal of optimism. You can also see the palms that self seeded and are growing well in front of the agaves. I am really glad I didn't move them now as I had planned because they may be just what is needed to fill up an empty space.

Even gardening can be sad sometimes.


Rohrerbot said...

Oh my goodness. I was just watching a video on this today out of Austin on Texas Central Gardening and it was their main topic. It seems this year has been a busy year for these insects on our agaves. I hope your other ones are not affected. I was hoping that they'd stay in Texas, but it appears that they're here:) Good luck!!

Esther Montgomery said...

Those females must have strong teeth!

But how sad that the plant dissolves. Do the weevil offspring drink the soup?


Mo said...

Rohrerbot, Thank you for the good luck wishes, I feel sure I will need them!

They would need a strong stomach to drink it Esther, the smell was foul! :)