Hedge-Parsley ID details
At one point, Minnesota observations of Hedge Parsley (Torilis) at iNat that have species level ID suggestions fell within two species:
iNaturalist: Upright Hedge-Parsley (Torilis japonica) aka Japanese Hedge Parsley
iNaturalist: Common Hedge Parsley (Torilis arvensis) aka Spreading Hedge-Parsley
As of Aug 19, 2023, there were (at iNat) 137 observations of T. japonica and 44 observations of T. arvensis.
While researching one of my own observations (back in Aug 2020) and trying to determine whether it was Torilis arvensis or T. japonica, I uncovered some information that is pertinent to many observations of Hedge Parsley, but specifically - for my part - those in Minnesota.
DATA ON PRESENCE IN MINNESOTA
In a 2020 email conversation with the MN DNR, I was told that "There are currently no records for Torilis arvensis in Minnesota. We are finding that T. japonica is fairly widespread." [1] In that email, links were provided to pertinent pages at EDDMapS (Early Detection and Distribution Mapping System) I rechecked those records in Aug 2023 and that statement remains true.
EDDMaps: Torilis arvensis
EDDMaps: Torilis japonica
I also can't find any other source listing T. arvensis as being present in MN other than the observations here at iNat. The Minnesota Wildflowers website does not have an entry for that species nor does it mention it on the species page for T. japonica.
IDENTIFYING DETAILS
[I focused on using the flowers for identification. See @csledge's comment below for info on how to use the fruit for identification.]
I'm providing sources for this information but the information was found on multiple sites and all sites I found were in agreement with the details.
Minnesota Wildflowers website
For T. japonica: "At the base of an umbel are 2 or more very narrow bracts that may be slightly spreading. Up to 8 bracts are at the base of each umbellet, though they are very small and hard to see."
pictures of these bracts can be seen at:
Minnesota Wildflowers website
University of Wisconsin Herbarium
iNaturalist: one of my observations
Wisconsin DNR website
"(Torilis arvensis; invasive) is not currently known in Wisconsin, but nationally is more common than T. japonica. It looks very similar to Japanese hedge-parsley but lacks the pointed bracts at the base of each umbel."
Wisconsin DNR: Japanese Hedgeparsley (Torilis japonica)
and...
"(Torilis japonica; invasive) has two or more pointed bracts at the base of each umbel. Otherwise the two plants are very much the same."
Wisconsin DNR: Spreading Hedgeparsley (Torilis arvensis)
Illinois Wildflowers website:
"For a long time, Common Hedge Parsley was incorrectly identified as Torilis japonica (Japanese Hedge Parsley). However, this latter species has about 8 linear bracts at the base of each compound umbel, and the bristles of its seeds have hooked tips. While Japanese Hedge Parsley occurs in Illinois, it far less common than Common Hedge Parsley. As a result of this misidentification, the distribution records within the state include observations of both species." For T. japonica "The bristles are straight to slightly curved; they do not have hooked tips."
Illinois Wildflowers: Common Hedge Parsley (Torilis arvensis)
summary:
Upright Hedge-Parsley (Torilis japonica):
- has bracts at the base of each flower umbrel even after it has gone to seed
- bristles on seeds are up-curved [2]
- bristles on seeds have hooked tips
Common/Spreading Hedge Parsley (Torilis arvensis):
- does NOT have bracts at the base of each umbrel
- bristles on the seeds are straight to slightly curved
- bristles on seeds have NO hooks on the tips
Unless a Torilis observation shows the underside of the umbrel such that the absence of bracts can be documented or a note has been made that the umbrels were examined in the field and found to absent of bracts, I don't think the observation can be identified as T. arvensis.
UPDATE: 3 Dec 2023
After reviewing all the Minnesota (MN) observations identified as T. arvensis, I was not able to find one that had defining features that proved it to be that species. Some observations had a defining feature that proved it to be T. japonica. Some weren't Torilis at all. Many didn't have flowers. Many that did have flowers were blurry and details weren't evident. And the rest had great photos of the top of the flower but not of the bottom. As of this writing, there are zero observations of T. arvensis here at iNat for Minnesota.
This is not to say that T. arvensis isn't present. It's impossible to prove a negative. T. japonica is considered an invasive plant in MN and was being monitored by the MN DNR. But by 2020 this was no longer the case. “DNR land managers on sites with Torilis japonica are finding it not to form dense cover or spread beyond disturbed area and the Minnesota Department of Agriculture’s noxious weed advisory committee risk assessment for Torilis japonica recommended not regulating it.” [1]
If Hedge-parsley is that invasive, then it is possible that T. arvensis may eventually make its way to MN. It is possible that the first record may be made by an observer at iNaturalist. Taking good, sharp photos of underside of the flower or the fruit will be important for monitoring whether a Torilis specimen is arvensis or japonica.
And, for what it’s worth, there are currently 42 observations identified as T. arvensis in Wisconsin. Since the Wisconsin DNR states it has not been found in that state, it may be worth reviewing those observations in the future.
SOURCES AND OTHER INFO/LINKS
[1] Aug 6, 2020 email from
Laura Van Riper
Terrestrial Invasive Species Program Coordinator | Division of Ecological and Water Resources
Minnesota Department of Natural Resources
[2] Friends of (Eloise Butler) Wildflower Garden website
EDDMapS info:
Early Detection and Distribution Mapping System (www.eddmaps.org) was designed to provide a more accurate picture of the distribution of invasive species. (from: https://www.fs.usda.gov/treesearch/pubs/37561)
Minnesota state agencies such as the departments of Natural Resources, Agriculture, and Transportation use EDDMapS to track and share invasive species occurrence information. EDDMapS does regular downloads from iNaturalist and if the EDDMapS verifiers concur with the reports, they enter EDDMaps. (Laura Van Riper, email cited above)
FINAL NOTE
While researching information on this subject, I found seemingly reliable websites (government or academic) that had photos for either of these two species that I suspect were misidentified. I am personally taking the information presented above as the 'facts' but not necessarily holding images identified as one species or another as 'proven factual'... if you catch the difference.