Predicting Evolutionary Consequences of Greater Reproductive Effort in Tripsacum Dactyloides, a Perennial Grass

To test the prediction that a mutation causing greater reproductive effort will result in reduced vegetative vigor, we compared the seed production, growth, and carbohydrate status of normal and pistillate genotypes of the grass Tripsacum dactyloides differing in seed production by up to fourfold. We evaluated the costs of reproduction by two methods: experimental manipulation of reproductive effort and comparison of highand low-yielding genotypes. Despite the large difference in seed production, normal and pistillate (high-yielding) genotypes did not differ in growth rate over a 1-yr period. Contrary to predictions, carbohydrate reserves in the high-yielding genotype were significantly higher at the peak of the seed ripening period. Stalk defoliation and complete removal of seed stalks reduced plant growth rate, total aboveground biomass, and biomass of vegetative storage organs, especially when plants were also under stress from biweekly defoliation. However, stalk removal caused increased rates of growth in the year after experimental manipulations. Reproductive tillers were costly to the plant in terms of lost meristems and therefore future plant size, but seed costs were contained within reproductive tillers of both genotypes, explaining the lack of a trade-off in the high-yielding, pistillate genotype. Although experimental reduction of reproductive effort revealed a cost of reproduction, this result could not be used to correctly predict the consequences of a gene for greater seed production

Abnormal synergies and associated reactions post-hemiparetic stroke reflect muscle activation patterns of brainstem motor pathways

Individuals with moderate-to-severe post-stroke hemiparesis cannot control proximal and distal joints of the arm independently because they are constrained to stereotypical movement patterns called flexion and extension synergies. Accumulating evidence indicates that these synergies emerge because of upregulation of diffusely projecting brainstem motor pathways following stroke-induced damage to corticofugal pathways. During our recent work on differences in synergy expression among proximal and distal joints, we serendipitously observed some notable characteristics of synergy-driven muscle activation. It seemed that: paretic wrist/finger muscles were activated maximally during contractions of muscles at a different joint; differences in the magnitude of synergy expression occurred when elicited via contraction of proximal vs. distal muscles; and associated reactions in the paretic limb occurred during maximal efforts with the non-paretic limb, the strength of which seemed to vary depending on which muscles in the non-paretic limb were contracting. Here we formally investigated these observations and interpreted them within the context of the neural mechanisms thought to underlie stereotypical movement patterns. If upregulation of brainstem motor pathways occurs following stroke-induced corticofugal tract damage, then we would expect a pattern of muscle dependency in the observed behaviors consistent with such neural reorganization. Twelve participants with moderate-to-severe hemiparetic stroke and six without stroke performed maximal isometric torque generation in eight directions: shoulder abduction/adduction and elbow, wrist, and finger flexion/extension. Isometric joint torques and surface EMG were recorded from shoulder, elbow, wrist, and finger joints and muscles. For some participants, joint torque and muscle activation generated during maximal voluntary contractions were lower than during maximal synergy-induced contractions (i.e., contractions about a different joint), particularly for wrist and fingers. Synergy-driven contractions were strongest when elicited via proximal joints and weakest when elicited via distal joints. Associated reactions in the wrist/finger flexors were stronger than those of other paretic muscles and were the only ones whose response depended on whether the non-paretic contraction was at a proximal or distal joint. Results provide indirect evidence linking the influence of brainstem motor pathways to abnormal motor behaviors post-stroke, and they demonstrate the need to examine whole-limb behavior when studying or seeking to rehabilitate the paretic upper limb

Genetic variation in ecophysiological and survival responses to drought in two native grasses: Koeleria Macrantha and Elymus Elymoides

Genetic variation in ecophysiological and survival responses to drought was studied in 2 northern Arizona native grass species, Koeleria macrantha (Ledeb.) Schult. (prairie Junegrass) and Elymus elymoides (Raf.) Swezey. ssp. elymoides (squirreltail). Low- and high-elevation populations of each species were compared in a greenhouse common garden experiment that included simulated drought. Leaf gas-exchange characteristics were significantly affected by simulated drought and often by population elevation, but gas-exchange responses to drought were similar for high- and low-elevation populations. Compared to high-elevation populations, low-elevation populations of both species had higher net photosynthetic rate and predawn water potential, and for E. elymoides had higher stomatal conductance. Leaf-level water-use efficiency did not differ between populations for either species. Populations also differed significantly in leaf morphological characteristics related to water use. Compared to high-elevation populations, low-elevation populations of both species had smaller leaves. Low-elevation populations of both species survived aboveground longer than high-elevation populations during drought, with a larger difference in K. macrantha than in E. elymoides. These results suggest strong selection for drought adaptation and water use along an elevational and water-availability gradient in native grasses. (English

Role of Student Services in Recruitment and Retention in the NAU School of Forestry Katherine

In times of declining enrollment, increasing budget constraints, increased FTE scrutiny, and the need for departments to justify their personnel, having a student services coordinator (SSC) might seem like a luxury position that is subject to elimination. Yet, we suggest that a SSC is crucial to forestry programs, and that the benefits far outweigh the costs. An effective SSC can provide personal attention and mentoring which are keys for successful recruitment and retention, therefore, increasing FTEs. These key activities are often neglected without a SSC, because everyone’s time is already overcommitted

Active Learning in a Web-based Introductory Course

The idea that people learn through knowledge reception is the most prevalent “common sense” assumption about learning and is the basis behind the lecture mode of instruction. In contrast, advocates of learner-centered education argue that learning occurs when meaningful knowledge is constructed by the learner being actively engaged with the learning material. Although many science-based classroom courses are using active- learning techniques, most web-based courses epitomize the passive method of instruction

The Future of a Prolific Variant of Eastern Gamagrass

Eastern gamagrass [Tripsacum dactyloides (L.) L.] is currently being selected for higher forage yield. A prolific variant which can produce up to 20 times the number and 3 times the weight of seeds of a normal plant was found in a wild population and is now instrumental in the breeding program. Could this prolific type spread in wild populations? Vegetative vigor of mature plants was assessed by clipping plants to a 7 cm height every two weeks throughout the growing season. The two types did not differ in dry weight of regrowth, suggesting that they tolerate defoliation equally. Seed germination was compared by determining the parentage of 1,043 seedlings emerging near a nursery containing 64% normal and 36% prolific plants. Based on counts of inflorescences and seeds in the soil, variant plants contributed up to 90% of the seeds in the area. However, only 29% of the seedlings established in the area came from prolific plants. The prolific variant was equal in vegetative vigor as an adult plant, and equal or at a disadvantage as a maternal parent. Since the condition is recessive, pollen production is extremely low, and high seed fecundity is offset by poor germination success, the prolific type is not expected to spread in the wild

Standing Our Ground: The Meaning of SAF Accreditation

Since its inception in 1935, the SAF accreditation program for forestry education has changed significantly. Initially, accreditation was a rating system of one’s alma mater to determine which graduates had the knowledge to be eligible for SAF membership versus those who needed more on‐ the‐job experience to qualify. Thus from the beginning, the focus of accreditation has been on quality of education. However, what constitutes “forestry education” has always been difficult for SAF to define for accreditation purposes. For example, a July 1935 Journal of Forestry article described “recreational forestry” as a branch of forestry or a separate profession. In the 1980’s, the SAF unease was exacerbated by a proliferation of bachelor’s or master’s degree options and as a result, by 1988 SAF began accrediting only curriculum with degree programs that met a relatively rigid set of SAF standards for an education in forestry. Since then, increasing demands on the profession, as well as on institutions of higher education indicated the need for an unprecedented level of flexibility regarding accreditation. SAF responded by adopting new standards based on outcomes rather than courses and accreditation is being granted to programs leading to an associate’s degree in forest technology. In addition, special standards have been developed for urban forestry and a task force is considering accreditation of nontraditional forestry programs generically being referred to as “terrestrial ecosystem management”. At the 7th UENR Biennial Conference, a number of presentations compared aspects of general natural resources education to SAF accredited forestry programs. The cry went up “...and that’s what’s wrong with accreditation!” without addressing the purpose of forestry education or the success in fulfilling its mission. This presentation will address issues associated with forestry education accreditation from “breaking new ground” at the turn of the 20th Century to “standing our ground” as we march into the 21st

Getting Students to Read and Think: Using Popular Literature in an Introductory Natural Resources Course

Lower level natural resource management courses are used to introduce majors to the discipline, recruit new majors, and/or to fulfill university general education requirements. Consequently, interests and backgrounds of students enrolled in the course can vary greatly, and finding an appropriate textbook can be challenging. There are many good introductory textbooks available but most are heavy on facts and are considered very boring by most students. In addition, many of these textbooks present natural resource management issues as “black and white” and thus do not encourage critical thinking. After dealing with these same issues every year for several years and finding myself bored reading the textbook, I challenged myself to find a better better way and have incorporated popular literature into my course to see if I could get the students better engaged in reading and critical thinking. The outcomes have been overwhelmingly positive and I continue to incorporate a variety of novels into my introductory natural resource management courses. Results indicate students are excited they “got to read a novel in a science class!” and they typically finished their reading assignments ahead of due dates. Class discussions and assignments based on the novels are supported by information from the textbook which motivated students to read their textbook and helped put natural resources management topics into context. In addition, comparing information in the novels to the textbook encouraged students to think critically and illustrated the complexity of natural resource management. I will describe the overall concept of using novels by using results of incorporating Barbara Kingsolver’s novel “Prodigal Summer” in a lecture-based introductory natural resources management course. I will describe how I modified my syllabus and how I used assignments from the novel to motivate students to read their textbook and think critically about natural resource management issues

Field Experience for Students Also Provides Critical Assistance for Family Landowners in the Southern Appalachians

The southern Appalachian region epitomizes changes in forest land ownership that have occurred throughout much of the US during recent decades. These changes include the divestiture of industrial forest lands, increased fragmentation, changing demographics, and a shift in management objectives to include nontraditional forest products. While there is broad consensus among Southern Appalachian landowners that sustainable forest management is desirable, there are relatively few examples to demonstrate how it can be applied at the scale of family lands. The Western Carolina Forest Sustainability Initiative (WCFSI) was formed in 2001 as a partnership between the Natural Resource Conservation and Management (NRCM) Program at Western Carolina University (WCU), local land trusts, and The Conservation Fund to promote sustainable forest management on family lands. The director of WCFSI is a NRCM faculty member and the workers employed by WCFSI are undergraduate forestry interns who work year-round designing and actually implementing sustainable forest management practices on non-industrial private forest lands. Students also have opportunities to work on WCFSI projects through coursework. The initiative has provided undergraduate students income and a wide range of hands-on plus “minds-on” experiences in the application of sustainable resource management practices, while also helping families manage their forest lands in an ecologically and economically sustainable way. This presentation will describe the WCFSI and will illustrate how the program achieves its learning outcomes for the students while also achieving sustainability outcomes for the landowners