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Ranunculaceae: Ceratocephala testiculata
No full textCeratocephala testiculata is a small annual herb growing from a slender, often shallow, fibrous root system. The entire plant is usually less than 5–10 cm tall. Stems are typically branched at the base, sparsely hairy to nearly glabrous, and not woody. Leaves are all basal, forming a loose rosette, deeply divided into narrow linear to lobed segments. Basal leaves can reach up to about 6–12 cm long, though each leaflet segment is quite narrow, usually 1–3 mm wide. The leaves are covered with short, stiff hairs. Flowering occurs very early in the spring (often March–April). Flowers are solitary or in small clusters, each about 5–10 mm across. Each flower has 5 yellow, shiny, oblong petals, rounded to slightly obovate in shape, about 5–8 mm long and 3–5 mm wide, giving the flower a compact appearance and 5 shorter, green sepals, typically about 3–5 mm long and approximately 1.5–2 mm wide. The sepals are somewhat ovate to lanceolate in shape and slightly pointed at the tip. Flowers contain numerous stamens and several pistils. The fruit is a small, spiny bur composed of a cluster of nutlets—each nutlet is ovoid, 3–5 mm long, armed with hooked or curved projections. Bur buttercup matures and sets seed rapidly—often by late spring or early summer. Seeds are small, yellowish or brown, and equipped for dispersal by animals via the hooked spines. Bur buttercup is an introduced species and is now a widespread weed in South Dakota, most common in dry, disturbed grasslands, roadsides, overgrazed pastures, sandy sites, and compacted soils, especially in the western part of the state.https://openprairie.sdstate.edu/nativeplant/1284/thumbnail.jp
Dairy and Food Science Student Newsletter, December 16, 2025
No full texthttps://openprairie.sdstate.edu/dairy_student-news/1025/thumbnail.jp
Geraniaceae: Erodium cicutarium
No full textErodium cicutarium is an annual or biennial taprooted herbaceous species that initially forms a rosette with stems that typically grow 10–50 cm tall. The stems are slender, often reddish or purplish, and may be hairy or smooth. Leaves are 3–10 cm long, pinnately divided with narrow lobes, giving a fern-like appearance. Flowering occurs from spring through late summer (April–September). The flowers are borne singly or in small clusters on slender stalks. Flowers are small, typically 1–2 cm across, with five pink to purple petals that measure 10 to 15 mm in length and about 4 to 7 mm in width. Their edges are smooth, and the petals have a delicate, slightly translucent texture that enhances the visibility of the darker venation. The sepals are generally smaller than the petals, measuring about 6 to 9 millimeters long and 1.5 to 3 millimeters wide. They are often covered with fine hairs, giving them a slightly fuzzy appearance. Flowers are bisexual, with five stamens and a pistil. Fruit is distinctive: a long, beak-like style attached to a small seed capsule, this stork\u27s-bill shape aids in seed dispersal by “catapulting” seeds away. Common Stork’s-bill is introduced and widespread in South Dakota, growing in disturbed sites, roadsides, fields, and grasslands, especially in drier areas.https://openprairie.sdstate.edu/nativeplant/1307/thumbnail.jp
Asteraceae: Leucanthemum vulgare
No full textLeucanthemum vulgare is a perennial herbaceous plant typically growing 20 to 80 cm tall. It has a fibrous root system with short rhizomes. The stems are erect and glabrous to sparsely hairy. Leaves are alternate and simple, with the basal leaves being spatulate to ovate-lanceolate, measuring about 5 to 15 cm long and 1 to 4 cm wide, and the upper stem leaves becoming smaller and more lance-shaped. Leaf margins are irregularly toothed or lobed, and the surfaces are mostly smooth. Leaves are sessile or have very short petioles, usually less than 1 cm. The inflorescence is a solitary flower head (capitulum) borne on a long peduncle, flowering from late spring through summer (May–August). The flower heads are 3 to 6 cm in diameter, composed of numerous white ray florets approximately 15 to 25 mm long and 4 to 7 mm wide surrounding a central disc of yellow tubular disc florets about 5 to 8 mm long. The flower head is subtended by several rows of green to straw-colored bracts (involucre) that are lanceolate to ovate and typically 10 to 20 mm long. The fruit is a small achene about 2 to 3 mm long. In South Dakota. Oxeye daisy is native to Europe but widely naturalized and considered invasive in South Dakota. It is commonly found in disturbed prairies, grasslands, meadows, roadsides, and disturbed sites.https://openprairie.sdstate.edu/nativeplant/1321/thumbnail.jp
Boraginaceae: Onosmodium bejariense
No full textOnosmodium bejariense is a perennial herbaceous plant with a woody base, growing 30 to 90 cm tall with erect, branched stems densely covered in coarse, spreading hairs that give a rough texture. The alternate leaves are lanceolate to narrowly ovate, 5 to 15 cm long and 1 to 4 cm wide, with entire to slightly wavy margins, short petioles and a rough, hairy surface. Flowering occurs in mid-summer (May–July). The flowers are born in terminal and axillary cymes. Each flower has five sepals fused at the base, each sepal about 5–8 mm long, narrowly lanceolate and hairy forming a calyx tube about 6 to 10 mm long with pointed lobes. The corolla consists of five white petals fused into a tubular shape 10 to 15 mm long and 4 to 6 mm wide. with 5 hairy, green to yellow-tinged, triangular lobes at the tip that close the mouth of the tube. A long white style projects from the tube and remains long after the petals wilt away. The flower contains five stamens epipetalous (attached near the base of the corolla tube), with slender filaments and yellow anthers enclosed within the tube. The pistil has a superior ovary with a single style approximately 6 to 8 mm long, extending beyond the stamens. And terminating in a bifid stigma with rounded lobes about 1 to 2 mm wide. Fruits develop from August through September as four brown, smooth, slightly glossy nutlets, each about 3 to 5 mm long. Western false gromwell is native to South Dakota, typically found in sandy or rocky prairies, open woodlands, and well-drained upland sites across much of the state.https://openprairie.sdstate.edu/nativeplant/1338/thumbnail.jp
Boraginaceae: Phacelia hastata
No full textPhacelia hastata is a perennial herbaceous plant growing 15 to 60 cm tall from a fibrous root system with a woody base. The roots are slender and moderately deep, anchoring the plant in well-drained soils. Leaves are mostly basal and alternate along the stem, petiolate, with petioles 3 to 10 cm long. Blades are lanceolate to ovate-lanceolate, 5 to 15 cm long and 2 to 6 cm wide, often deeply lobed or toothed, covered with a dense layer of fine, silvery hairs that give the plant a distinctive silvery-gray appearance. The flowers are arranged in coiled cymes and bloom from May through August. Each flower has five fused sepals forming a calyx 3 to 5 millimeters long and about 1.5 to 2 millimeters wide, covered with fine hairs. The corolla is bell-shaped to funnel-shaped, pale blue to lavender, about 10 to 15 mm long and 6 to 10 mm wide, with five lobes at the mouth. The flower contains five stamens with prominent yellow anthers that extend beyond the corolla. The pistil has a superior ovary with a style about 6 to 8 mm long ending in a bifid stigma. The fruit is a small capsule containing several seeds. Silverleaf phacelia is native to South Dakota and is typically found in dry, open habitats such as prairies, rocky slopes, and sandy or gravelly soils, mainly in the western and central parts of the state.https://openprairie.sdstate.edu/nativeplant/1346/thumbnail.jp
Multi-Source Remote Sensing–Based Soil Moisture Prediction Using Machine Learning
No full textSoil moisture (SM) plays a central role in climatic and environmental processes, influencing shear strength of soil, agricultural productivity, land–atmosphere interactions, and hydrologic functioning. However, accurately estimating SM across diverse climatic regions remains challenging due to spatial heterogeneity, limited in situ measurements, and inconsistencies in sensor resolution. Machine learning (ML) and remote sensing offer promising avenues for improving SM prediction, yet many existing approaches struggle with generalization across climatic gradients and often fail to capture temporal variability. This study integrates multi-source satellite and climate datasets, including SMAP L4_SM, MODIS land surface temperature, Daymet meteorological variables, and in situ observations from the U.S. Climate Reference Network (USCRN), to evaluate the potential of ML models for daily SM prediction across nine U.S. climatic zones. All datasets were harmonized to a common 9 km spatial and daily temporal resolution using Google Earth Engine and Python preprocessing workflows. Three ML algorithms, such as, Extreme Gradient Boosting (XGBoost), Support Vector Regression (SVR), and Multilayer Perceptron (MLP), were trained and evaluated under zone-specific experimental cases. Across the nine climatic zones, XGBoost consistently provided the strongest predictive performance, achieving an R² of 0.43 in Zone 6A, particularly in arid and mixed-dry environments. MLP demonstrated comparable performance in colder regions, while SVR showed greater stability in humid zones. These findings highlight the sensitivity of model performance to climatic regimes and emphasize the importance of region-specific modeling strategies. The results also suggest that future hybrid frameworks incorporating additional variables, such as vegetation indices, topographic features, and soil properties, could further enhance SM prediction accuracy and transferability. Overall, this study provides a scalable, data-driven approach for regional soil moisture estimation and offers practical insights for applications in precision agriculture, drought monitoring, hydrological modeling, and climate resilience planning. The work also underscores the need for continued research in temporal modeling, multi-sensor data fusion, and spatial validation techniques to strengthen the robustness of SM prediction across heterogeneous landscapes
Characterization of Major Foliar Fungal Species Affecting Cucurbits in South Dakota
No full textCucurbit crops comprise the largest area in vegetable production in South Dakota (USDA 2022). Information on the prevalence, distribution, and fungicide sensitivity of their fungal pathogens are unknown. This study characterized the major foliar fungal species affecting cucurbits in South Dakota through a 2-year, state-wide survey. Between 2023 and 2024, 789 leaves were recovered from pumpkin, cucumber, watermelon, squash, and bottle gourd. Alternaria spp. (70.72% of leaves) Fusarium spp. (6.84%), Podosphaera xanthii (4.18%), both Alternaria spp. and Fusarium spp. (3.42%), and both Alternaria spp. and Podosphaera xanthii (1.90%), Stagonosporopsis spp. (1.27%) and other genera of fungi (4.94%) were identified using a combination of microcopy and sequencing of the internal transcribed spacer (ITS) region of ribosomal DNA , with 6.72% of leaves exhibiting no sporulation. A subset of Alternaria spp. isolates (n=238) recovered from cucumber and pumpkin leaves were selected for multi-locus ((translation elongation factor-1α (TEF1), glycerldehyde-3-phosphate dehydrogenase (GAPDH), and RNA polymerase II core subunit (RPB2)) sequencing to determine species. Unique haplotypes (n=46) of Alternaria spp. were identified by concatenating loci. A combined maximum likelihood and Bayesian phylogeny revealed 18 haplotypes, comprising 133 isolates, clustered with Alternaria alternata and A. tenuissima (syn. A. alternata). Haplotype visualization with minimum spanning networks identified no influence of region, production environment, or host on genetic diversity. Koch’s postulates were fulfilled by inoculating cucumber ‘Straight 8’ plants inoculated with four representative isolates of A. alternata. Morphological and phylogenetic comparison supported the identification of fungal isolates as A. alternata. Three representative isolates of the most abundant A. alternata haplotypes and haplotype 14 from the survey screened in-vitro for fungicide sensitivity to pyraclostrobin (FRAC 11) and penthiopyrad (FRAC 7). All representative isolates of A. alternata screened were sensitive. A randomized complete block cucumber ‘Straight 8’ field trial was conducted in 2024 and 2025 under natural Alternaria spp. pressure to assess efficacy of fungicide applications on disease progression or yield. Treatments A) Kocide (M01), B) Fontellis (FRAC 7), Inspire Super (FRAC 3 + FRAC 9), or Quadris (FRAC 11) rotated weekly with Bravo Weatherstik (M5), C) Fontellis (FRAC 7), Switch (FRAC 9 + FRAC 12), or Cabrio (FRAC 11), rotated weekly with Bravo Weatherstik (M5) controlled disease progression compared to treatment D) water control. Treatment C was significantly more effective at reducing foliar disease progression than other treatments. No significant differences in marketable yield or USDA grades were observed among treatments
Spatiotemporal Habitat Use, Sex-Specific Movement, and Site Fidelity of Walleye in Lake Sharpe, SD
No full textWalleye Sander vitreus are a popular sportfish among anglers in South Dakota with large economic impacts to local communities. A popular destination for Walleye anglers is Lake Sharpe, a 25,000-ha reservoir on the Missouri River, in central South Dakota. Gill net catches in Lake Sharpe show high annual variation, prompting concern that gill net catch rates may be poorly related to population abundance. A better understanding of Walleye movement and distribution could lead to increased precision in annual abundance estimates and improved active management that increases angler success. The goals of this study were: 1) determine spatiotemporal movement patterns of Walleye in Lake Sharpe, 2) identify how hydroelectric discharge impacts Walleye movement, and 3) identify how sex and seasons impact Walleye movements and site fidelity. In total, 91 Walleye (404-653 mm TL) were captured and implanted with V13 (n = 79) or V13AP (n = 12) transmitters from April 2018 to July 2020. Acoustic telemetry data were collected from June 2018 through December 2020 from 28 passive receivers distributed throughout Lake Sharpe. Walleye use was generally high in the riverine zone (14.2 % ± 1.6% SE), DeGrey (13.1% ± 1.6% SE), the upper lacustrine (12.4% ± 1.5% SE), and the Cedar Creek areas (12.3% % ± 1.5% SE). Zones with the lowest predicted use were Hipple Lake (4.0% ± 0.7% SE), lower lacustrine (5.0% ± 0.8% SE), and stilling basin (5.5% ± 0.8% SE). We found no significant seasonal changes in Walleye zone use. Discharge effects were zone-specific and limited, with only tailrace zones showing significant positive response to increased discharge. Movement averaged 23.9 km per month (95% CI: 19.5 - 29.2 km), with no significant differences between seasons or sexes. Males exhibited significantly higher movement than females during post-spawn and fall periods. Site fidelity patterns varied by season, with highest fidelity observed during winter and pre-spawn periods and lowest during the spawning season. These findings highlight the complex interplay between seasonal behavior, habitat preferences, and environmental conditions that should be considered for optimal Walleye management in Lake Sharpe
Elvin Bjorklund Papers
Full text linkElvin C. Bjorklund live from 1908 to 1990 and worked for Soil Conservation Service as deputy state conservationist. He dealt with soil and water conservation needs inventory, flood prevention, and watershed protection. This Collection contains Elvin Bjorklund Soil Conservation Service papers. It is comprised of records on Soil Conservation Service’s works, events, and personnel. Likewise, it has photographs of personnel, conservation, and events