Need pictures of the critters.

If they are termites, they won't affect your plants.

Termites eat wood, not plants.

-Babka

Yes. If redwood is the only wood around, they will eat it. I have redwood fence boards that have termites happily having lunch, and dinner, and breakfast....

-Babka

They probably are eating the cardboard. They love love love cardboard. Next time you might want to skip it. once it is gone they'll move on to the raised beds.

Get rid of them. It is only a matter of time before they decide your house would be nice, too.

I agree on getting rid of them I have seen them swarm from the ground and go find a new home. Your garden is only a snack and your house will be the main course.

They won't eat your house, if it isn't wet. Or rather, they're probably already eating your house. You find the damage and you repair it.

Dry wood termites WILL eat your house if it isn't wet. The only way to keep ahead of things is to be aware and if you see the telltale droppings (looks like celery salt anywhere, do some investigating. To get back to the OP, yes they will eventually eat your raised bed boards. Old growth redwood was denser and more resistant to bugs. Nowadays the redwood won't last as long. Sure looks good, though!

-Babka

Yup in Cali,dry wood termites will eat your house if it isn't wet.Back a few years ago when we went thru one of the BIG fire storms,some guy whose house burned down put a sign in his front yard,"Finally no more termites". I say California should change it's logo from the golden state to the "termite" state.LOL,jmo of course.We battle those dang things here along the coast all the time.Think they are getting immune to the chemicals that kill them..

Kathi

lol @ "Finally, no more termites". Sad situation from the fire, but that sign would about sum it up!

I suppose I will have to be the first to bear the bad news.... Termites WILL eat some of your vegetable plants... The first year that I built my garden and raised beds, I planted broccoli. When they were just forming the broccoli heads, one or two fell over in the dirt. I investigated them to find out what made that happen. There were tunnels IN and through the stem! The termites had hollowed out the stem, and it had just crumpled in half. I pulled out the affected plants and saw the little rice-sized creepers scurrying away. Each day, a couple more broccoli plants crumpled over until the little buttholes had decimated every last one. Not to mention that now year 4 of growing, one of my raised beds (which sound like the same ones you (OP) built) is almost to the point of being unusable.

California should be known as the "Termite "state.Even folks in newer homes are fighting them..

Those creatures started eating our fence last year, so I started to find ways of solutions. Over a couple of years, termites can damage or completely destroy house’s wooden bearing structures. There are several ways to fight them in this article. These are the chemical products against termites: liquid insecticide fipronil,imidacloprid granules,boric acid, termidor fipronil foam and so on. They are very harmful to humans and pets, so be careful while using something like that.

They eat wet wood..fast! If you dry out the wood..they will move on. But,people go crazy and rip everything out and poison the world also. Remove the wet rot wood and only replace that. In your case- its all the cardboard. Redwood three years in the ground sounds too soon. But eventually sure, especially used as a planter.

Stanofh- I really do enjoy your posts here in the CA gardening forum, you keep this place going when it gets slow, but you are miss-informed regarding termites. There is more than just wet wood, subterranean termites. The DRY wood ones eat your rafters. Our house has been tented 3 times to get those buggers. Go Here to find out more.

-Babka

There's more to termites then I knew!