The “Bad” Grass List

By Kevin Noon and Cathy Lewis

We currently know of or suspect several grass species as dangers to our dogs. These species have two characteristics of the floret that make them particularly insidious. The basal extension of the lemma (sheath or bract) around the grass floret comes to a very sharp point as the floret matures and dries out at the end of clip_image002the plants’ growing season. And the lemma is covered with tiny hairs pointing away from the sharp basal point. As the florets mature, they fall off easily. They can be inhaled into the throat or lungs of a dog, swallowed, caught between the toes, become lodged in the fur, or fall into the ear canal. Once attached, the direction of the basal hairs creates a “barbed” effect which keeps the floret from backing out of the fur or tissue. As the animal moves the floret constantly migrates forward pushing the pointed base further into the tissue.

Once inside the tissue these florets have been known to migrate anywhere inside the body including through organs, down the spinal column, through the eyes, and up the limbs. Aside from the damage and infection caused by the migration, some florets carry bacteria that can cause serious infections depending on where they are located.

The following is a list of the most common grasses with these characteristics that dog owners and veterinarians across the country have identified. The worst known hazards are shown in red.  The links provided contain additional information and/or photographs.

Cheatgrass/Downy brome      Bromus tectorum      Photos in site Gallery

http://www.fs.fed.us/database/feis/plants/graminoid/brotec/all.html

http://plants.usda.gov/java/profile?symbol=BRTE

http://www.ubcbotanicalgarden.org/potd/2007/05/bromus_tectorum.php

Ripgut Brome       Bromus rigidus

http://plants.usda.gov/java/profile?symbol=BRDIR

 

Canada Wild Rye    Elymus canadensis    Photos in site Gallery

Photos: http://plants.usda.gov/gallery/pubs/elca4_003_pvp.jpg

http://tenn.bio.utk.edu/vascular/database/vascular-database.asp?CategoryID=Monocots&FamilyID=Poaceae&GenusID=Elymus&SpeciesID=canadensis

Virginia Wild Rye      Elymus virginicus

http://plants.usda.gov/java/profile?symbol=ELVI3

Great photos: http://tenn.bio.utk.edu/vascular/database/vascular-database.asp?CategoryID=Monocots&FamilyID=Poaceae&GenusID=Elymus&SpeciesID=virginicus

Foxtail Barley      Hordeum jubatum     Photos in site Gallery

Awn photo: http://www.ubcbotanicalgarden.org/potd/2005/09/hordeum_jubatum.php

 

Needle and Thread      Stipa comate

http://plants.usda.gov/java/profile?symbol=HECOC8

Western Needlegrass      Stipa occidentalis

http://plants.usda.gov/java/profile?symbol=ACOCC

California Needlegrass      Stipa pulchra      CA only

http://plants.usda.gov/java/profile?symbol=NAPU4

Sleepygrass/Tall Needle grass      Stipa robusta

http://plants.usda.gov/java/profile?symbol=ACRO7

http://www.lycaeum.org/~sputnik/Plants/Images/Stipa.robusta.jpg

Winter Redtop/winter bentgrass/ticklegrass       Agrostis hiemalis or Agrostis hyemalis

http://plants.usda.gov/java/profile?symbol=AGHY

http://www.eeob.iastate.edu/research/iowagrasses/speciespages/AgrosHiema/AgrosHiema.html

Red Three-Awn     Aristida longiseta

http://plants.usda.gov/java/profile?symbol=ARPUL

http://www.agf.gov.bc.ca/range/RangeID/Plants/ArisLong.html

Single-Awn Aristida      Aristida orcuttianas      CA,AZ,NM,TX

http://plants.usda.gov/java/profile?symbol=ARSCO

Oldfield Threeawn      Aristida oligantha

http://plants.usda.gov/java/profile?symbol=AROL

http://www.eeob.iastate.edu/research/iowagrasses/speciespages/AristOliga/AristOliga.html

Nimblewill      Muhlenbergia schreberi

This plant was suggested as problematic by a plant biologist at U of Minnesota. On inspection, it doesn’t appear immediately to have an aggressive awn, but better to provide the information as potential hazard than not.

http://plants.usda.gov/java/profile?symbol=MUSC

http://plants.usda.gov/gallery/pubs/musc_002_php.jpg

http://plants.usda.gov/java/largeImage?imageID=mupa6_001_avd.tif

 

NRCS database (main): http://plants.usda.gov/

Line drawings of various grasses/identification guide: http://www.caf.wvu.edu/~forage/library/cangrass/content.htm

More photographs of many grasses: http://www.invasive.org

 

© Cathy Lewis & Kevin Noon, 2010

{ 10 comments… read them below or add one }

Tracie Wilson May 7, 2010 at 2:22 pm

Very informative site! THANK YOU for putting this information together in one spot for the rest of us dog lovers!!!

Tracie Wilson May 7, 2010 at 2:23 pm

Have you heard anything negative regaring Indian Grass?

admin May 10, 2010 at 4:49 pm

You’re welcome! I’m glad you find it helpful :-) .

admin May 10, 2010 at 4:54 pm

I have been told that a dog in Ohio had an infection where recovered plant material was identified as Indian Grass. We do have some in our training field, and I was pulling pieces apart all fall to examine. It’s all so soft I’m perplexed at how it could have caused a problem, unless there are different varieties identified as Indian Grass and another type features a more aggressive awn. I can hope we will have better information to work from as we are able to get more recovered material identified. If anyone needs assistance in that regard, please contact me.

Danelle Oliver September 9, 2010 at 7:18 pm

This is my first year growing warm season grasses in a test plot. One variety in my mix is Indian Grass. I was told that it can be dangerous to our dogs. After examining it and finding no barbs on the seeds. I wondered if the danger was that it could be easily inhaled due to the small light weight seeds that it drops, late summer early fall. A time we usually are running our dogs in fields.

Mark Christenson December 19, 2010 at 8:17 pm

Hi. I am a Veterinarian from Minnesota and received a question on new CRP plantings in Western North Dakota. They are wanting to try “Basin WildRye” in some CRP fields. Is there any reports of this being a problem in dogs like Canada wild Rye.

Thank you any info appreciated

Justin Feeman January 8, 2011 at 10:31 pm

Hello, I was forwarded this website from all around
dogloving stepmother who has trained, professionally groomed, and
competed with dogs. I like dogs, but I like grasses better. I think
that labeling grasses as “bad” is an injustice to the grass. Most
of the grasses in your “bad grass” list are native grasses that are
important to the ecosystem and have been in existence much longer
than Spaniels. I suggest that you redefine your “bad grasses” as
cautionary grasses or grasses incompatible with dogs so that people
do not assume that the listed grass species are bad for anything
but dog recreation.

k Smith January 13, 2011 at 8:03 am

I would like to put these info in our magazine. Thank you

Sarah parker January 17, 2014 at 12:15 am

Hello,

I was wondering if you had any information about whether purple fountain grass migrates in a similar manner as the plants listed above. My dog may have inhaled some through his nose, and I am extremely worried. About a week and a half ago he was playing next to a purple fountain grass bush and suddenly came out of the garden with a severe sneezing fit. He sneezed about 30 times in a row, and has continued to have bouts of sneezing since. Before that day he had never been a sneezer. So far the vets have tried two different procedures and haven’t found the plant in his nose, and he is going in for a ct scan tomorrow. It is possible that he sneezed it out, but i worry he may not have given his continued bouts of prolonged sneezing since that day (and even after his nose was flushed). Cancer, alergies, an infection, and nasal mites have also been ruled out. If anyone had info. On purple fountain grass it would be much appreciated.

admin January 17, 2014 at 12:24 am

Hi Sarah. I can appreciate your concern and wish I could offer some assistance, but I’m not familiar with this particular grass. The ongoing sneezing would worry me, too. I hope that this resolves quickly for your dog.

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