Climate Matching Map
| Attachment | Size |
|---|---|
| climatematch-bothriochloa_ischaemum-arizona-20260324.pdf (1.12 MB) | 1.12 MB |
1. Question 1
Yes
1
Very High
This species has been naturalized beyond its native range (Europe, Asia, and north Africa). The majority of these naturalized populations are within North America focused in the south-central United States.
“Bothriochloa Ischaemum (L.) Keng (gbif)”. n.d. https://gbif.org/species/2704102.
“Taxonomy - GRIN-Global Web V 1.9.8.2 Bothriochloa Ischaemum”. n.d. https://npgsweb.ars-grin.gov/gringlobal/taxonomydetail.aspx?id=7483.
Clayton, Megan K., J. L. Foster, K. C. McCuistion, T. W. Teinert, and M. M. Lesak. 2017. “Introduced Bluestem Grasses: Management on Native Lands”. Texas A&M AgriLife Extension.
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
2. Question 2
Yes
2
Very High
Yes. Naturalized populations are heavily focused in Arizona. This Arizona's arid climate reflects the species's natural climate in southern Europe, western Asia, and northern Africa. Habitat that this species occurs include, Mediterranean scrub land, desert, and grasslands.
“Texas Invasives - Bothriochloa Ischaemum”. n.d. http://texasinvasives.org/plant_database/detail.php?symbol=BOISS.
Service, Agricultural Research. 2026. “Bothriochloa Ischaemum (L.) Keng Var. Ischaemum GRIN-Global”. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomydetail?id=300076.
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
3. Question 3
Yes
2
Very High
Yes. This species has been recorded to be invasive within the United States by being a threat to native grasslands within the southwestern United States by inhibiting the growth of native plant species, reducing arthropod abundance, and reducing avian diversity. It is also listed as a noxious weed in both Arizona and New Mexico.
Harlan, Jack R., Robert P. Celarier, W. L. Richardson, Magaret Hoover Brook, and K. L. Mehra. 1958. “Studies on Old World BluestemsII.”
Arizona, University of. 2026. “Yellow Bluestem Grass | AZ Invasive Plants”. https://azinvasiveplants.arizona.edu/invasive-plant/yellow-bluestem-gra….
.org, Invasive. n.d. “Yellow Bluestem (Bothriochloa Ischaemum (L.) Keng)”. https://www.invasive.org/browse/subject/55440?tab=subject-info.
4. Question 4
Yes
3
Very High
Yes. This species is invasive within areas of the Southwestern United States which mirrors climatic conditions of arid regions of north Africa and western Asia. Habitat that this species occurs include, Mediterranean scrub land, desert, and grasslands.
“Texas Invasives - Bothriochloa Ischaemum”. n.d. http://texasinvasives.org/plant_database/detail.php?symbol=BOISS.
Swearingen, J, and C Bargeron. n.d. “Yellow Bluestem: Bothriochloa Ischaemum (Cyperales: Poaceae): Invasive Plant Atlas of the United States”. https://www.invasiveplantatlas.org/subject.html?sub=55440.
Service, Agricultural Research. 2026. “Bothriochloa Ischaemum (L.) Keng Var. Ischaemum GRIN-Global”. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomydetail?id=300076.
5. Question 5
Yes
1
High
There seems to be one species within the same genus (Bothriochloa pertusa) that is invasive in Australia that has similar climatic conditions of the American southwest.
Fusco, Emily J., John T. Finn, Jennifer K. Balch, Chelsea Nagy, and Bethany A. Bradley. 2019. “Invasive Grasses Increase Fire Occurrence and Frequency across US Ecoregions”. Proceedings of the National Academy of Sciences 116: 23594-99. doi:10.1073/pnas.1908253116.
Bean, T.M., and C.A. Hannum. 2009. “Invasive Grasses: Cause for Concern. In: Backyards \& Beyond”. 3(3). Tucson, AZ: Arizona CooperativeExtension, College of Agriculture and Life Sciences, University of Arizona. 4-5.. https://cales.arizona.edu/backyards/sites/cals.arizona.edu.backyards/fi….
Lebbink, Gabrielle, and Rod Fensham. 2022. “The ‘lawnification’ of Australia’s Eastern Grassy Woodlands: The Past, Current and Likely Future Spread of an Invasive Perennial Grass, Bothriochloa Pertusa”. Biological Invasions 25 (6).
6. Question 6
No
0
High
As mentioned before, this species occupies a wide range within its native range including dry, arid environments such as north Africa and western Asia. These climates are synonymous with the American southwest including Arizona. Additionally the majority of its invaded range is in the southwestern United States (particularly Texas). However, most of the GBIF occurrences for this species occur outside of the climate match.
“Bothriochloa Ischaemum (L.) Keng (gbif)”. n.d. https://gbif.org/species/2704102.
“Texas Invasives - Bothriochloa Ischaemum”. n.d. http://texasinvasives.org/plant_database/detail.php?symbol=BOISS.
Arizona, University of. 2026. “Yellow Bluestem Grass | AZ Invasive Plants”. https://azinvasiveplants.arizona.edu/invasive-plant/yellow-bluestem-gra….
7. Question 7
Yes
1
Very High
Yes. There have been numerous studies that show the ability of this species to dominate native plant communities which it occupies through competition and even potential allelopathy.
Harmoney, Keith R., and Karen R. Hickman. 2004. “Comparative Morphology of Caucasian Old World Bluestem and Native Grasses”. Agronomy Journal 96 (6): 1540-44.
DaSilva, S. L., K. G. Lyons, and S. Schwinning. 2022. “ KR Bluestem (Bothriochloa Ischaemum Var. Songarica) Has Some Direct Allelopathic Effects on Germination But Not on Seedling Growth in a Native Non-Native Mixed Community of Warm Season Grasses in Texas”. Plant and Soil 480 (1): 637-49.
8. Question 8
Yes
1
High
This species is known to be unaffected by prescribed burns due to being rhizomatous and having the ability to create vast dense monocultures. While little work has been done studying the effect of fire regimes in the context of Bothriochloa ischaemum invasion, this species has the ability to change them.
Dee, J. R., S. M. Thomas, S. D. Thompson, and M. W. Palmer. 2016. “Long‐term Late Season Mowing Maintains Diversity in Southern US Tallgrass Prairie Invaded by Bothriochloa Ischaemum”. Applied Vegetation Science 19 (3): 442-53.
Clayton, Megan K., J. L. Foster, K. C. McCuistion, T. W. Teinert, and M. M. Lesak. 2017. “Introduced Bluestem Grasses: Management on Native Lands”. Texas A&M AgriLife Extension.
9. Question 9
No
0
Very High
While there is evidence that this species affects both arthropod and an avian communities in the environments which it is invasive in, there is no direct evidence of the species having any toxic effect on these communities. In fact, this species was introduced for grazing needs in the southwestern United States.
Kouri, J. D., E. Rust, and L. Souza. 2026. “Intra‐and Inter‐Specific Ecological Impacts Vary Across a Gradient of Abundance of an Invasive Species, Bothriochloa Ischaemum, in a Mixed‐Grass Prairie”. Ecology and Evolution 16 (3).
Hickman, K. R, G. H Farley, R. Channell, and J. E. Steier. 2006. “Effects of Old World Bluestem (Bothriochloa Ischaemum) on Food Availability and Avian Community Composition Within the Mixed-Grass Prairie”. The Southwestern Naturalist 51 (4): 524-30.
10. Question 10
No
0
High
No. The plant is commonly grazed by livestock and does not pose a threat to the movement of both human and livestock due its size.
Arizona, University of. 2026. “Yellow Bluestem Grass | AZ Invasive Plants”. https://azinvasiveplants.arizona.edu/invasive-plant/yellow-bluestem-gra….
Swearingen, J, and C Bargeron. n.d. “Yellow Bluestem: Bothriochloa Ischaemum (Cyperales: Poaceae): Invasive Plant Atlas of the United States”. https://www.invasiveplantatlas.org/subject.html?sub=55440.
Service, Agricultural Research. 2026. “Bothriochloa Ischaemum (L.) Keng Var. Ischaemum GRIN-Global”. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomydetail?id=300076.
11. Question 11
Yes
1
Very High
This plant has the ability to reproduce (spread laterally) by stolons and/or rhizomes.
Liu, Ying, Peng Li, Guo Ce Xu, Lie Xiao, Zong Ping Ren, and Zhan Bin Li. 2017. “Growth, Morphological, and Physiological Responses to Drought Stress in Bothriochloa Ischaemum”. Frontiers in Plant Science 8. doi:10.3389/fpls.2017.00230.
Ahring, R. M, and J. R. Harlan. 1961. “Germination Characteristics of Some Accessions Of’Bothriochloa Ischaemum’(L.) Keng.”
Texas, Native Plant Society of. n.d. “Https://Www.npsot.org/Posts/Invasive-Plant/Bothriochloa-Ischaemum-Var-Songarica/”. https://www.npsot.org/posts/invasive-plant/bothriochloa-ischaemum-var-s….
12. Question 12
No
0
Very High
There are no evidence for this occurring in both its native range and invasive range. However, fragments of the plant that contains the root crown or a viable fragment of rhizome can result into new individuals.
Liu, Ying, Peng Li, Guo Ce Xu, Lie Xiao, Zong Ping Ren, and Zhan Bin Li. 2017. “Growth, Morphological, and Physiological Responses to Drought Stress in Bothriochloa Ischaemum”. Frontiers in Plant Science 8. doi:10.3389/fpls.2017.00230.
“Bothriochloa Ischaemum (yellow Bluestem) Datasheet (CABI)”. 2015. http://www.cabi.org/isc/datasheet/112759.
Ahring, R. M, and J. R. Harlan. 1961. “Germination Characteristics of Some Accessions Of’Bothriochloa Ischaemum’(L.) Keng.”
13. Question 13
Yes
1
Very High
Yes. This commonly produces viable seed but also have the ability to reproduce via fragments of rhizomes.
Liu, Ying, Peng Li, Guo Ce Xu, Lie Xiao, Zong Ping Ren, and Zhan Bin Li. 2017. “Growth, Morphological, and Physiological Responses to Drought Stress in Bothriochloa Ischaemum”. Frontiers in Plant Science 8. doi:10.3389/fpls.2017.00230.
Ahring, R. M, and J. R. Harlan. 1961. “Germination Characteristics of Some Accessions Of’Bothriochloa Ischaemum’(L.) Keng.”
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
14. Question 14
Yes
1
Medium
Due to its morphology and life history of being a perennial, copious viable seed per year seem to be possible.
Kouri, J. D., E. Rust, and L. Souza. 2026. “Intra‐and Inter‐Specific Ecological Impacts Vary Across a Gradient of Abundance of an Invasive Species, Bothriochloa Ischaemum, in a Mixed‐Grass Prairie”. Ecology and Evolution 16 (3).
Dee, J. R., S. M. Thomas, S. D. Thompson, and M. W. Palmer. 2016. “Long‐term Late Season Mowing Maintains Diversity in Southern US Tallgrass Prairie Invaded by Bothriochloa Ischaemum”. Applied Vegetation Science 19 (3): 442-53.
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
15. Question 15
Yes
1
Very High
Yes. There is documented cases of this species having high germination with little to no treatment.
Liu, Ying, Peng Li, Guo Ce Xu, Lie Xiao, Zong Ping Ren, and Zhan Bin Li. 2017. “Growth, Morphological, and Physiological Responses to Drought Stress in Bothriochloa Ischaemum”. Frontiers in Plant Science 8. doi:10.3389/fpls.2017.00230.
Ahring, R. M, and J. R. Harlan. 1961. “Germination Characteristics of Some Accessions Of’Bothriochloa Ischaemum’(L.) Keng.”
16. Question 16
Yes
1
Medium
Little evidence can be found about the exact timing of sexual maturity for this species. With that in mind, we can defer to the reproductive capabilities of other relatives of the species.
Gabbard, B. L, and N. L. Fowler. 2007. “Wide Ecological Amplitude of a Diversity-Reducing Invasive Grass”. Biological Invasions 9 (2): 149-60.
Dee, J. R., S. M. Thomas, S. D. Thompson, and M. W. Palmer. 2016. “Long‐term Late Season Mowing Maintains Diversity in Southern US Tallgrass Prairie Invaded by Bothriochloa Ischaemum”. Applied Vegetation Science 19 (3): 442-53.
17. Question 17
Yes
1
High
This species is a perennial leading it for the opportunity for a single individual to produce seed every year. It has been shown that it has an extensive flowering period from February all the way to September .
Arizona, University of. 2026. “Yellow Bluestem Grass | AZ Invasive Plants”. https://azinvasiveplants.arizona.edu/invasive-plant/yellow-bluestem-gra….
“Texas Invasives - Bothriochloa Ischaemum”. n.d. http://texasinvasives.org/plant_database/detail.php?symbol=BOISS.
Swearingen, J, and C Bargeron. n.d. “Yellow Bluestem: Bothriochloa Ischaemum (Cyperales: Poaceae): Invasive Plant Atlas of the United States”. https://www.invasiveplantatlas.org/subject.html?sub=55440.
18. Question 18
No
0
High
There seems to be no evidence that this special is dispersed by mammals, birds, or any domestic animals.
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
“Texas Invasives - Bothriochloa Ischaemum”. n.d. http://texasinvasives.org/plant_database/detail.php?symbol=BOISS.
Hickman, K. R, G. H Farley, R. Channell, and J. E. Steier. 2006. “Effects of Old World Bluestem (Bothriochloa Ischaemum) on Food Availability and Avian Community Composition Within the Mixed-Grass Prairie”. The Southwestern Naturalist 51 (4): 524-30.
19. Question 19
No
0
High
No. The natural dispersal for this species is via wind dispersal, but there is no evidence for it dispersing over 100m. Seeds are long oval shaped, compressed in edge view, suggesting some dispersal via wind but not over long distances.
“Texas Invasives - Bothriochloa Ischaemum”. n.d. http://texasinvasives.org/plant_database/detail.php?symbol=BOISS.
Kouri, J. D., E. Rust, and L. Souza. 2026. “Intra‐and Inter‐Specific Ecological Impacts Vary Across a Gradient of Abundance of an Invasive Species, Bothriochloa Ischaemum, in a Mixed‐Grass Prairie”. Ecology and Evolution 16 (3).
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
20. Question 20
Yes
1
High
While predominately wind dispersal, this species seems to have its dispersal benefited from establishing near roadsides.
Gabbard, BL. 2003. “The Population Dynamics and Distribution of the Exotic Grass, Bothriochloa Ischaemum”. The University of Texas at Austin.
Evaluation Notes
This species has been thoroughly documented to be an invasive species within the American Southwest. While there are gaps in the literature (mostly around its reproductive and phenology life history), the current literature strong supports the majority of the notes mentioned within this report.
Total PRE Score
18
20
88
