A reevaluation of the use of rhizome scars to age plants of Trillium erectum (Melanthiaceae)1.

PREMISE OF STUDY: Herbaceous perennials are important long-lived plants in North American forests. Trillium has been used as a model organism to examine the effects of ecological processes on age structure in herbaceous forest perennials. Here, the methods of aging Trillium rhizomes are critically examined. • METHODS: Rhizomes of seedlings, single-bract plants, three-bract nonflowering plants, and flowering plants of Trillium erectum were examined. The patterns of cataphyll and scape scars on rhizomes were examined with respect to demographic category. • KEY RESULTS: Trillium rhizomes produce two cataphyll scars per year on single-bract, three-bract nonflowering, and flowering plants. Scape scars were only evident on rhizomes of three-leaved nonflowering and flowering plants. The percentage of intact rhizomes ranged from 10-67% for three-bract nonflowering plants, and 0-51% for flowering plants. Rhizomes in all demographic categories had evidence of recessing tissues from the oldest portion of the rhizome indicating that accurate age estimates are not possible on many plants. • CONCLUSIONS: Accepted methods of aging Trillium rhizomes have significant drawbacks. The primary problem is that rhizomes rot from the oldest portions in all demographic categories. A second problem is that plants producing multiple scape scars in a given year could mistakenly be counted as multiple years. Finally, confusing terminology and misrepresentations in Trillium literature suggests that many previous studies did not correctly determine age. Given the challenges of aging Trillium, we suggest that future studies use rhizome aging to study early demographic stages only and the ecological processes that influence their growth.

Psychopathology as a predictor of medical service utilization for youth in residential treatment.

Rising health care costs have led to an emphasis on identifying factors that contribute to medical service utilization. Previous research has suggested an association between youth psychopathology and service utilization; however, prospective studies among high-risk populations are needed. The current study examined youth psychopathology as a predictor of subsequent medical service utilization among a large sample (N = 536) of youth entering residential treatment. Youth psychopathology and medical status were assessed at intake, and medical service utilization was tracked across the duration of the residential placement. Results indicated that higher levels of psychopathology predicted greater youth medical service utilization, even after controlling for the presence of a diagnosed medical condition. Internalizing problems was a significant independent predictor of utilization, but externalizing problems was not. These findings highlight the association between mental health and medical service utilization and suggest that effective behavioral health services may be helpful in reducing costly medical service needs.

Prevalence of physical health problems among youth entering residential treatment.

OBJECTIVE: To examine the prevalence of physical health problems among youth entering residential treatment. PATIENTS AND METHODS: The sample included 1744 youth (mean age: 14.6 ± 1.8 years) entering a large residential treatment program between 2000 and 2010. Youth received an intake medical evaluation, including a review of available records, detailed medical history, and physical examination. Medical conditions present at the time of the evaluation were recorded by the examining physician and later coded by the research team. Only diagnoses recognized by the International Classification of Diseases, 10th Revision, were included in the analyses. To maintain the focus on physical health problems, behavioral and emotional disorders listed in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision were excluded. Obesity, acne, and allergies were also excluded. RESULTS: Approximately one-third (33.7%) of youth had a physical health diagnosis at the time of intake. Asthma was the most prevalent condition diagnosed (15.3% of the sample). Girls were significantly more likely to have a diagnosis than were boys (37.1% vs 31.5%). Age was not associated with diagnostic status. Rates of physical health conditions differed significantly by ethnicity: black (36.4%) and white (35.4%) youth had the highest rates, and Hispanic youth (23.2%) had the lowest. CONCLUSIONS: Youth who enter residential treatment have high rates of physical health conditions. These problems could complicate mental health treatment and should be considered in multidisciplinary treatment planning.