How to figure out which pest is eating the sunflowers
Q
Something is eating my sunflower leaves! I don’t see any insects, but there are chunks missing out of the leaves. How do I find out what’s causing this damage? I don’t want to spray anything that will kill the butterflies, ladybugs, bees and other “nice” bugs.
A
Your photo shows light to moderate damage on the leaves. Something’s definitely eating them, but it doesn’t look like the plant is in any danger of being stripped of all its leaves.
Often, insects and other critters will do their damage in the night and early morning hours, then scurry for cover when the sun comes up. If you haven’t seen anything during the day, wait until nightfall, grab a flashlight and start peeking underneath leaves.
Some types of insect damage can be pinned onto a specific culprit rather easily. For instance, I noticed a lot of neat, perfectly round holes in my rosebushes’ leaves. At first, I thought my son (who was about 7 at the time) had taken my hole punch and gone to town on my garden. Then I found out we had been visited by leafcutter bees. (He was off the hook … this time.)
When looking for your leafeating culprits, also look for rolled leaves, cocoons, eggs and frass (poop). These clues point to some kind of caterpillar: omnivorous loopers, hornworms, leafrollers or army worms. If the damage isn’t too extensive, I would let them be. There are many beneficial insects that dine on these critters and other pests. If you feel that you must do something, handpicking is the most environmentally friendly way to manage these pests.
Remember — all those beautiful butterflies and moths started out as caterpillars!
Q
I saw a little mouselike creature in my lawn. It was bigger than a mouse but smaller than a gopher. It had a short tail and was kind of chunky-looking. What is it?
A
You probably saw a vole (also called a meadow mouse). Unlike mice, they are strictly an outdoors animal. My cats love to hunt them because, compared with other prey, they are stupid, fat, slow and easy to catch.
They are not as destructive as gophers, but they will eat plant material and gnaw on tree bark. They tend to travel along the same routes, going from one burrow opening to another and flattening grass and ground cover along the way.
Like all rodents, they can reproduce quickly and periodically become a problem. They are considered a nongame animal in California, which means that if they are causing damage, you are allowed to kill them by any legal means. Trapping is OK. Explosives are not.
To discourage voles from settling in your garden, remove as much cover as possible so they become visible to predators. Protect trees with wire mesh around the trunks. Fumigation is not effective since their burrows are shallow and have many openings. Trapping is easy because they are stupid. Just place a mousetrap along one of their paths. You can bait it with an apple slice or peanut butter, but, again, they are really stupid and will just walk into an unbaited trap. Have questions? Email gardening@scng.com.
For more master gardening resources, visit ucanr.edu/sites/ RiversideMG for Riverside County, mgsb.ucanr.edu for San Bernardino County, celosangeles.ucanr.edu/UC_ Master_Gardener_Program for Los Angeles County and mgorange.ucanr.edu for Orange County.