[APWG] Article: Two native forb "winners" in chemical war with spotted knapweed

[Tony Frates]

Heterotheca villosa (Chrysopsis villosa) has allelopathic properties  
and examples of two studies relating to its use specifically to combat  
Cirsium arvense follow:


(1)

Integrated management of the invasive species Cirsium arvense, Canada  
thistle, and Phragmites australis, common reed: Using ecologically  
based control measures at each stage of the invasion process
Juneau, Kevyn J.. Michigan Technological University, ProQuest  
Dissertations Publishing, 2013. 3565329.

Preview:

http://search.proquest.com/openview/e913e789ef15669127a9c7b17dc4a34f/1



(2)

Suppressing Canada thistle establishment with native seed mixes and  
resulting cost analysis
Fasching, Steven Michael. North Dakota State University, ProQuest  
Dissertations Publishing, 2013. 1535528.

Preview:

http://search.proquest.com/openview/6dfe9477a43a97c87b1a87a46d7f4b0b/1




Local observations suggest that Heterotheca villosa helps to keep  
other invasives at bay in remnant patches of native plant communities.


Tony Frates
Utah Native Plant Society









Quoting "Riibe, Lindsey" <lriibe at blm.gov>:

> A short story from the In Defense of Plants blog, "The Enemy of My Enemy is
> My Friend"
> http://www.indefenseofplants.com/blog/2017/6/12/the-enemy-of-my-enemy-is-my-friend
>
> Not all native plants are equally susceptible to spotted knapweeds effects.
> Two native forbs stand out above the rest in being able to cope with the
> allelochemicals released by spotted knapweed. Enter silky lupine (*Lupinus
> sericeus*) and blanketflower (*Gaillardia grandiflora*). Where these plants
> occur alongside spotted knapweed, other natives seem to do a bit better.
> This made researchers curious. What was it about these two species?
>
> ​2006 research paper sited in the story:​
> Oxalate contributes to the resistance Gaillardia grandiflora and Lupinus
> sericeus to a phytotoxin produced by Centaurea maculosa
> ​
> https://www.researchgate.net/publication/7375276_Oxalate_contributes_to_the_resistance_Gaillardia_grandiflora_and_Lupinus_sericeus_to_a_phytotoxin_produced_by_Centaurea_maculosa
> ​
>
> ​Anyone know of other studies on native "winners" known to neutralize
>  allelopathic toxins ​of invasive weeds?
>
>
>
> Lindsey Riibe
> Bureau of Land Management
> Plant Conservation Program Assistant
> 503-808-6230
>
> National Seed Strategy for Rehabilitation and Restoration
> <https://www.blm.gov/programs/natural-resources/native-plant-communities/national-seed-strategy>
> Plant Conservation Alliance <http://www.plantconservationalliance.org/>
> Seeds of Success
> <https://www.blm.gov/programs/natural-resources/native-plant-communities/native-plant-and-seed-material-development/collection>