Ground Squirrels Damaging Yucca? Maybe Not.

Q. I have ground squirrels that killed my agave. They dig around it, eating the roots, and finally killed it. What do I do? How should I protect it?

One of the antelope ground squirrels common in the Mojave desert.

A. The ground squirrel you're seeing is referred to as an antelope ground squirrel. They are omnivorous which means they will eat insect grubs if they find them. But when food is scarce my feeling is they will go after anything.

One of the American agave used for landscaping in Las Vegas. The rock mulch has been disturbed by these ground squirrels.

            I am guessing but I think what you're seeing is an attack first by the agave weevil in the spring with the ground squirrels digging up the grubs and eating them. In any regard, it's always best to drench the soil around these agave weevils with an insecticide when spring temperatures begin to warm up. In our climate it is normally the end of March or the first part of April. This application protects all agave. If you have agave and want to keep them, you must protect them from agave weevil in the spring. I don't know of any organic methods that have been tested that I can recommend.

Agave weevil babies (larvae) are found eating the soft and succulent tissue found at the base of leaves and the roots or crown. They attack mostly agave, laying their eggs in when spring temperatures begin to warm in the spring. This is usually around the end of March or early April in the Las Vegas climate.

            American agave is native to the desert Southwest. Irrigate them with a lot of water slowly (so the water can go deep) and then hold off watering them for at least two or three weeks during the summer. Watering infrequently, but allowing the roots to dry between irrigations, will get them growing. The plants are thought to store water in their fleshy leaves. Water them less often if you don’t want them to grow but maintain their size. In any regard, it's probably going to be best if they are watered slowly, like rainfall in the desert.

One of the many kinds of American agave with root weevil or weevils. American agave is one of the hardest hit by agave weevils.

Leaf Browning Due to Insecticide

Q. I am hoping you can advise me on how to save my rose bushes I planted last spring. I sprayed my them accidentally with a concentrated insecticide, not diluted. The next morning the leaves looked like wilted spinach and I cried. Will the bushes die?  A friend told me I should have applied it to the soil.

Rose leaf scorch and death due to concentrated insecticide application. They will grow back.

A. They will come back. You burned the leaves with the concentrated insecticide. You should see new leaves and growth popping out in a week or so. During this time be careful not to overwater. Water them normally or even less often if they do not have leaves.

Always follow the label directions when applying and don’t listen to friends. Application depends on the insecticide. Some insecticides are root systemic and applied on the soil around the roots and watered in. Others are foliar and applied to the leaves.

You do not know which is which unless you read the label. The label will tell you how to apply it, when to apply and the application rate.

Japanese Blueberry With Orange Leaves a Sign of Leaf Death

Q. My water accidently turned off for two weeks and my Japanese Blueberries are all orange. I do see new growth on the edge of the branches. Is the tree shedding old leaves? Did the cold snap in November cause this?