I xerascaped my front yard 2 years ago, and used a nice selection of Agave's and grasses. Recently one of my Agave's started dropping the lower leaves to the ground. I just thought it was a natural process at first but it continued until the whole plant looked like it was collapsing. I started pulling lower leaves and was suspecting some kind of rot or something. To my horror, the entire upright crown fell over while I was inspecting the bottom.
First signs full infestation
The whole core of the plant was infested with large cream colored grubs with dark brown heads, and they had eaten the root and core of the Agave turning it into a dark smelly mush.
I have researched to find out what happened and discovered this is an Agave Snout Weevil. These were from Mexico and some desert areas, but have now become one of the top 100 invasive species.
Agave snout beetle weevils
Concerned for the rest of my plants, I started digging for treatments and prevention. Once the Agave is infested it is difficult to save it, but if tackled early enough, not impossible. Treatment to kill the weevils and grubs is a systemic insecticide, drenched in the area. This can also be done as a prevention on so far healthy Agave's, as they drink it in and any beetles that try to infest it are killed.
My plants are watered by drip, so I will be getting the product that can be mixed with water, and poured on and around the plants. I dug deeper and found that you should not use it on any Agave or Yucca that is blooming, because it will travel through the entire plant and would be toxic to bees.
I just wanted to put this out there for any other xerascapers, or desert dwellers that like Agave's in the landscape. Unfortunately if people do not try to get control early, the hatching beetles can travel a good distance to infest other plants.
There is some additional info here:
https://debraleebald...tion-treatment/
Edited by Skywatcher, 25 August 2019 - 06:41 PM.
