Can anyone tell what's eating my plants?

May 11, 2020 9:54 AM

Can anyone tell what's eating my plants?

Here are some pictures. The plants that are being eaten are lettuces and broccoli rabe. There are not holes in every plant and some other species planted nearby have no visible damage.

Is there anything I can do about this?

posted by jeb to Home & Garden (11 answers total)

Can you say where you live? Could help narrow it down.
posted by showbiz_liz at 10:08 AM on May 11, 2020

Response by poster: Oh, sorry! Los Angeles, California.
posted by jeb at 10:16 AM on May 11, 2020

My money's on bugs :)

Seriously - can you see any evidence of insect life around the plants? Butterflies (or moths, at night), little critters crawling under the leaves, etc.?

Are there new holes this morning? Or is this a creature that has since moved on, maybe a larva that's grown and flown away?
posted by amtho at 10:21 AM on May 11, 2020

I am also in L.A. and this looks like the earwig damage I see on my plants. On the one hand, earwigs eat things like aphids but they dearly love to chomp holes in lettuce or chard and they have been eating some of my viola petals down to the nub. This is a pretty good guide to various ways of getting rid of them.
posted by corey flood at 10:21 AM on May 11, 2020 [1 favorite]

Response by poster: Seriously - can you see any evidence of insect life around the plants? Butterflies (or moths, at night), little critters crawling under the leaves, etc.?

So the last two pics I posted, I thought maybe those little spots were some type of eggs. But in general, yes, I see butterflies, ladybugs, spiders and other sorts of many-legged creatures around the plants all the time. My yard is like a jungle. There are also a lot of birds, squirrels, possums, and rats.

Are there new holes this morning?

Definitely new holes this morning.

Sorry for threadsitting but I feel like answering these clarifying questions is more in keeping with the spirit of the law. Thanks!
posted by jeb at 10:29 AM on May 11, 2020

It’s insects, most likely larvae (chewing damage, not sucking), and not bird or mammal or gastropod (all of which would be more damaging). You can apply diatomaceous earth around the area to help keep crawlers and walkers off.

It’s not (currently) a big problem;whatever it is is browsing and moving on, not devouring huge swaths of leaf.

It’s good your yard is a jungle, creating a wide variety of diverse habitats attracts diverse species and diverse predators and helps limit catastrophic pest damage. So keep up the good work and be nice to your spiders, ladybirds, lacewings, mantises etc. You could also consider buying beneficial insects.
posted by SaltySalticid at 10:36 AM on May 11, 2020 [2 favorites]

Best answer: Cabbage looper. The white butterflies are not butterflies they are agents of veggie doom. Beneficial insects will do nothing to kill these bastards you need to use organicB.t. spray. At my center we sell both the monterey brand and safer brand but It should be the B.t. kurstaki strain- brand itself doesn't matter. It will only kill lepidopterans, and it's harmless to mammals, birds and non-targeted insects. They tend to attack brassicas but also lettuces- one time I cut open a pepper to find a little green visitor YUCK. If you spray the affected plants once a week the leaves will build up the bacterium and any caterpillars that nibble will die. In about a month you will notice many fewer holes.
posted by Homo neanderthalensis at 11:01 AM on May 11, 2020 [3 favorites]

Best answer: The cabbage looper is attacked by numerous natural enemies, and the effectiveness of each seems to vary greatly. Most studies note the effectiveness of wasp and tachinid parasitoids

This and more good info regarding loopers from UF entomology.
posted by SaltySalticid at 7:24 PM on May 11, 2020

Yeah- I've never seen a single available natural enemy go after them in any numbers to spare my veggies, and to be frank as a home vegetable gardener for most of my life- beneficial insects for sure have their uses, as my backyard army of ladybugs can attest too- BUT beneficials are WAY overblown as solutions to the worst of backyard pests. The problem is very much in vitro vs in vivo- a lab or even a lab garden is WAY different then a regular backyard or home garden, and the things ag scientists can control for when they test beneficials in their labs and lab gardens/greenhouses are things those of us who work and don't have the time to baby our backyards or who live in cities and therefore can have neighbors with more attractive plants whoops there go our good bugs- CANNOT control for. Caveat- I *think* praying mantises will go for loopers, unlike most others, but my mother has a phobia so that's the one beneficial I am not allowed to bring home and therefore cannot claim experience to. The other one that works is Trichs, but they are hard to apply/find. The advantage of the B.t. kurstaki spray is that unlike even most other organic sprays, you CAN use it with beneficials because as it's specific to lepidopterans it won't hurt any non-butterfly species at all. So fuck it- get the spray and the mantises/trichs- but not the ladybugs/lacewings/etc as they don't go for loopers. They do go for the aphids and scales and my carpet-bombing the garden with them has reduced my aphid load this year considerably, so if you have other bug issues consider them too.
posted by Homo neanderthalensis at 8:54 PM on May 11, 2020

Best answer: Any little white moth/butteryflies fluttering about? Then you've got cabbage worms.
posted by Grandysaur at 10:56 PM on May 12, 2020 [1 favorite]

Response by poster: Yep, it turned out to be cabbage loopers. I got the spray, thanks.
posted by jeb at 7:18 PM on May 18, 2020