In case you wondered too: Why crows are digging up the grass

That’s one of many dug-up planting strips we’ve noticed lately. You might have caught crows in the act of doing the digging; one reader asked us recently why they were “tilling.” By chance, we found the answer while covering this month’s North Highline Unincorporated Area Council meeting for our smaller site White Center Now. Marta Olson from the King County Noxious Weed Program was asked about it while talking to NHUAC about an unrelated topic. The crows are after “chafer beetles,” she explained, describing those bugs as invasive non-natives that have been spreading after first turning up near Sea-Tac. We hadn’t heard that before, so we’ve been researching. Here’s some scholarly info from just north of the border. The basic explanation is that the beetle’s larvae love grass roots, and crows – among others – find the larvae irresistibly delicious.

31 Replies to "In case you wondered too: Why crows are digging up the grass"

  • newnative December 8, 2019 (3:17 pm)

    Well! I saw this a few weeks ago but it was a crow tossing dirt from the rain gutter on Safeway. There was a line of dirt all up the block wherever there were rain gutters on buildings. 

  • honey bee December 8, 2019 (3:27 pm)

    I am so glad you shared this! I have been walking with friends and we have seen this all over Westwood,  Fauntleroy and North Shorewood, been wondering!Thanks!

  • Rr December 8, 2019 (3:46 pm)

    Hmm..interestingly the raccoons have been doing this same thing around our neighborhood. First time in a decade I’ve seen this behavior so wide spread (and damaging) wonder if they’re also preying upon this same larva?

  • dsa December 8, 2019 (3:52 pm)

      That’s one good thing I’ve heard about crows. Thank you

  • AMD December 8, 2019 (4:04 pm)

    This whole time I’ve been blaming the raccoons and now I feel terrible.  If any raccoons are reading this, I’m terribly sorry, guys.  I shouldn’t assume it’s always you digging up my grass just because it has been you every time before.  I’ll get my facts straight next time before accusing innocent critters.

    • jno December 8, 2019 (5:05 pm)

      I’ve been mistakenly blaming the wild rabbits. Sorry, buns.

      • Christine Hackett December 8, 2019 (7:30 pm)

        My yard and parking strip have been “crow-ized”…..did not have a clue as to why…thanks for the info

    • TrashPanda December 9, 2019 (7:55 pm)

      No worries!

    • Felix Grounds December 15, 2019 (2:02 pm)

      If any raccoons are reading this, we have bigger problems than dug up grass.

  • Just wondering December 8, 2019 (4:28 pm)

    I was wondering why the moss against the curb was turned up.  Way to go crows!

  • waikikigirl December 8, 2019 (4:43 pm)

    This has been going on for a few years, you should had seen St. Bernadettes soccer field a year or so ago just take the picture above but then in a whole soccer field!

  • Richard Maloney December 8, 2019 (4:51 pm)

    We were concerned about the apparent problem with the planting strip, so The Better Half did some research and learned to just leave things alone.  Let the crows do their thing because the greater problem is caused by the beetles.  

  • Also John December 8, 2019 (5:09 pm)

    I absolutely love crows.  One of the few species that has been documented building tools.  Extremely smart.  If you get up and close you can see how beautiful looking they are.

  • Rr December 8, 2019 (6:37 pm)

    Actually I followed the link in the article and it does say that raccoons dig up turf to get at these too, I know what I’ve seen has been more consistent with larger digging patterns and coincide with nights of audible raccoon activity.

    • WSB December 8, 2019 (7:13 pm)

      Yes, various things I found indicate other critters seem to like these bugs too but we have sctually seen the crows in action, again just today (flew off as we approached, so photo op lost).

  • Lee December 8, 2019 (7:42 pm)

    There were a few dozen crows digging around in the open grassy area near the south baseball field in Lincoln Park. Thought it was a bit odd as I passed, but that explains it.

  • Graciano December 8, 2019 (7:45 pm)

    If you have really good grass, they leave it alone. If you have some bare spots, they will tear it apart.Last year the crows torn up the play field at St. Bernadette school, this year I did see them doing the same thing.  they seem to be moving outwards for Seatac.

  • BMC December 8, 2019 (7:56 pm)

    So what’s the cure? I tried sprinkling chilli pepper powder and Maybe? they went away? Its supposed to work with cats. Any other ideas? Its actually quite destructive to lawns.

    • WSB December 8, 2019 (8:02 pm)

      A couple of commercial sites have suggestions. Nematodes are mentioned frequently:
      https://www.cbc.ca/news/canada/british-columbia/battling-the-chafer-beetle-1.3480757

      Also: Keeping the grass longer, or replacing it altogether, or at least diversifying ..we have planting strips that host other plants such as yarrow, and haven’t seen this problem in those areas.

    • Michael December 8, 2019 (9:45 pm)

      I’d suggest letting them rid the area of the invasive pests, which themselves may kill your grass. If the crows are successful, the result might be just one replanting, rather than repeatedly to repair the bug damage.

    • Susan December 9, 2019 (8:35 am)

      There may be a more effective and humane option. My neighbor bought a fake dead crow and the real crows have stayed away from his lawn since.  Though now that I know it’s invasive insects that they’re eating, I’m letting them snack freely on my lawn.

    • Richard Maloney December 9, 2019 (11:43 am)

      A few years back we had problems with birds eating the germinating seeds in the garden.  After re-planting a couple of times I realized it wasn’t bad seed, too little water, or the wrong depth.  The birds loved our prospective garden.So, it was off to Cash n Carry for a gallon of hot sauce.  It was applied liberally.  We didn’t want to kill these thieving birds.  Just maybe a burning mouth, maybe a bellyache.But sadly it turned out that the birds just loved Mexican.  We saved the garden by finally applying mesh over the rows.  Lesson learned.

  • mnw December 8, 2019 (8:57 pm)

    This is from September. I literally have no grass left in this section…they have moved on to tearing up my actual front yard now. đŸ˜•

  • KayK December 8, 2019 (9:59 pm)

    If we could only interest them in ripping out some other invasives like the English Ivy or BlackberriesđŸ¤ª

  • AMD December 8, 2019 (10:38 pm)

    As a helpful add: our front lawn was seriously destroyed in this manner in the spring (as were several others on the block).  The grass grew back on its own, without any intervention from us, by the fall.  It’s being dug up a second time now, but to a much lesser extent.  Takeaways for those who are concerned: your grass will grow back, even if you do nothing to make that happen.  The crows/raccoons/forest nymphs that are tearing it up are doing a solid job of eating an invasive species because there seems to be much less of it for them to get at (at least in my yard) in a very short period of time. 

  • steve December 9, 2019 (7:35 am)

    I must have raked about 200 lbs of loose grass. Those crows sure work hard! I wish they’d pull out the ivy and morning glory instead.  I read that these “grubs” are a recent import from the east coast.   I’m pretty distressed about what they’ve done to my yard. Then again,  screw it,  maybe the days of yard care are over.  Why do we obsess about yards anyway?  Long live the crow!

  • anonyme December 9, 2019 (8:31 am)

    I adore crows.  They are doing us a service.  As a former horticultural pro, I can tell you that this “damage” is likely short-lived; grass almost always grows back unless there is a cultural problem.  Getting rid of it is much more difficult.  I always advised clients to get rid of it anyway, as lawns are both unsustainable from a resource point of view, and high-maintenance from a cost/labor standpoint. I’m also suspicious as to the origin of this infestation. All of the new lawn installed along 35th as part of the sidewalk project is torn up. Wonder if the beetle larvae were in the grass seed, or soil products? Would be worth testing to see so that the City doesn’t spread the contamination.

  • mark47n December 9, 2019 (8:50 am)

    my backyard has been destroyed by my silly labs and my front yard is lovingly referred to as the’ natural area’. I mow when it starts to get tall but that’s about it. 

  • Mj December 9, 2019 (10:54 am)

    They are hungry, and they are providing aerating service for free!

  • 1994 December 9, 2019 (9:58 pm)

    Thanks so much for sharing the info. I have never seen this happen before. It seems to have started about a year ago and just keeps popping up everywhere. In my yard the raccoons , or possums, must be at work because I have these large divots that leave holes.  Sometimes the turf will go back into the hole nicely, other times not. 

  • anonyme December 10, 2019 (6:32 am)

    Birds are not affected by capsaicin as they don’t have heat receptors and cannot taste.  However, mammals (including cats, dogs, squirrels, raccoons, and opossums) can suffer severe pain and injury from this practice.  Spreading pepper on the ground where it can be walked in by many ‘non-offending’ species is irresponsible and cruel. Squirrels can experience eye damage from rubbing their eyes after handling pepper treated seed.   How would you like to have cayenne pepper rubbed in your eyes?   There are other ways to deter unwanted wildlife – or just live and let live.

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