This response confronts the inaccurate statements about the validity of the Salt River Vegetation Assessment. As a researcher, scientist, and biostatistician, I know the report is completely valid. However, not everyone has my background, so I provided scholarly proof that this type of ASSESSMENT (note the lack of the words “research study‘) is completely valid and scientifically grounded. The University of Arizona is a prestigious institution that would not produce anything inferior or lacking in the proper scientific rigour, methodological standards, or ecological relevance expected of land-grant university research and Extension work. Below is the Rebuttal, as well as an academic review of the assessment below the rebuttal.
Certain advocacy groups are criticizing the University of Arizona’s April 2025 Vegetation Assessment of the Salt River Horse Management Area, with The Salt River Wild Horse Management Group topping the list. These groups dispute its legitimacy because it was not published in a peer-reviewed journal. The argument shows a fundamental failure to understand how ecological monitoring and land management operate within practical settings. Please read the first few paragraphs. Also of note, this is written by a non-scientist, with no formal research training most likely named Simone Van der Salm (Netherlands is not her real name). Ms Van der Salm is the president of the Salt River Wild Horse Management Group and ironically, Ms Van der Salm is NOT a United States citizen, perhaps why she is at ease disparaging the University of Arizona.
Professional range scientists and ecologists at the University of Arizona Cooperative Extension developed the technical field report, which serves as the vegetation assessment. The assessment provides documentation of actual conditions while guiding resource management choices and delivering scientifically sound data to stakeholders, including land agencies, tribal partners, and the general public.
The scientific validity of management-grade research does not depend on peer review processes. The assessment’s quality is independent of peer-reviewed publication status because this format is unnecessary for credibility. Technical reports, field surveys, and unpublished data serve as the foundation for timely decision-making in all land and wildlife agencies and the Bureau of Land Management and the Forest Service. These include:
- Grazing permit evaluations
- Drought response actions
- Wildlife habitat management
- Emergency ecological assessments
This “gray literature” constitutes the primary source of information for both National Environmental Policy Act (NEPA) decision-making and agency decisions according to the National Environmental Policy Act (NEPA).
The validity of work depends on different factors other than peer-review status.
The success of applied ecological work depends more on methodological rigor than on peer-review status. Standard sampling protocols (dry-weight rank, comparative yield), transparent site selection methods, and data collection procedures should be used.
- Methodological rigor
- Appropriate interpretation grounded in ecological science.
- Clear documentation of findings.
The April 2025 assessment meets all of these criteria. The evaluation applied recognized vegetation assessment protocols, which combined dry-weight rank and comparative yield to document the distinct characteristics between grazing and non-grazing areas.
What motivations stem from these attacks against the assessment?
This report faces invalidation because of its non-journal publication status, but this argument lacks scientific-basis and demonstrates political dishonesty. This attack aims to deceive the public and decision-makers by equating essential research publications with field-based environmental assessments, although these represent entirely different approaches with separate objectives.
The application of this standard would render all the following assessments invalid:
- Most agency-led rangeland evaluation
- Federal wildlife habitat reports
- Environmental impact assessments
- Tribal ecological inventories
- Emergency drought response protocols.
No serious scientist or land manager would accept that logic.
Formal Comment on Vegetation Conditions in the Salt River Horse Management Area (April 2025)
The University of Arizona Cooperative Extension conducted a vegetation assessment in April 2025, which shows that excessive horse grazing in the Salt River Horse Management Area has led to ecological deterioration. According to the scientific report from the University of Arizona Cooperative Extension (UACE) 2025 the forage production level at 54.6 pounds per acre falls far below what wild horses require to meet their monthly food needs, since one horse needs 720-975 pounds of dry forage per month (UACE 2025 p. 1).
According to the assessment, annual forbs have taken over most of the landscape because these forage species lack nutritional value and exist only temporarily under D3 (Extreme Drought) conditions. The vegetation lacks sustainable forage resources, particularly for lactating mares and other vulnerable populations (UACE 2025, p. 1).
The continuous horse grazing has caused noticeable damage to native perennial shrubs by altering their health status and structural condition. The vegetation in areas that have been grazed exists in a hedged and stunted state. The height of jojoba shrubs in ungrazed control plots reaches 6.5 feet, but grazed areas show plants only at 1.5 feet according to SRH 3 versus SRH 14 (UACE 2025 p. 2). Wolfberry shrubs typically grow to 9 feet tall but were found to be hedged down to 1 foot, indicating that browsing pressure has exceeded natural recovery thresholds (UACE 2025 p. 2).
Through the fence-line picture on page 3, the study presents photographic evidence that shows the distinct difference in vegetation growth and quality between areas protected from horses and areas where horses are present (UACE 2025, p. 3). The combination of visual observations with precise measurements shows that this area’s natural state faces an ongoing threat of destruction.
According to the report, the high utilization rates observed in saltbush might decrease crude protein availability in jojoba and wolfberry plants, particularly during drought. Due to these findings, the nutritional worth of forage decreases significantly, making it impossible to support the basic food requirements of free-roaming equines (UACE 2025, p. 3).
Scientific evidence shows that the current horse population cannot sustain itself without active management measures, which include:
-Strategic population reduction
-Supplemental feeding (if removals are not pursued)
-Protecting habitats through fencing and the establishment of exclusion zones
Inaction threatens horses’ well-being through starvation while damaging the rangeland’s ability to recover and native plant diversity. This study presents evidence that should guide decision-makers to adopt evidence-based management practices in the Salt River region.
References
University of Arizona Cooperative Extension. (2025). Vegetation Assessment in the Salt River Horse Management Area, April 2025. Globe, AZ: Gila County Cooperative Extension, College of Agriculture and Life Sciences. The study document exists within an internal system which stakeholders can access here:
https://biologicaldiversity.org/programs/public_lands/pdfs/report-20250400-SALT-RIVER-HORSE-SUMMARY-REPORT-UA-WITH-IMAGES.pdf
Meen, R. (2000). The research study examines how saltbush utilization impacts its forage quality (Atriplex canescens) [UACE 2025 references this unpublished study].
©Dr. Meredith Hudes-Lowder, May 26, 2025
