Forage Kochia Research Articles

Cattle preference for forage kochia, crested wheatgrass, and velvet lupine

ABSTRACT Alkaloids in velvet lupine (Lupinus leucophyllus Douglas ex Lindl.) cause a crooked calf syndrome if the dam consumes the plant between d 40 and 100 of gestation. In spring calving operations, this coincides with late summer when annual grasses are mature and senescent in the Scabland region of eastern Washington. Velvet lupine is the only green-growing forb during this period on the annual grasslands and is readily consumed. Planting an alternative forage that is more palatable than velvet lupine may reduce the risk of crooked calves. Preference trials were conducted to compare the palatability of 2 varieties of forage kochia, ‘Immigrant’ (Kochia prostrata ssp. virescens) and the experimental line Otvsel (K. prostrata ssp. grisea), with crested wheatgrass (Agropyron desertorum [Fisch. ex Link] Schult.) and velvet lupine. Preferences were ranked by sequential Latin squares. The first trial consisted of four 4 × 4 Latin squares: 4 forages, 4 heifers, 4 d, and 4 feed locations. The most preferred forage was then removed and preference for the remaining forages was evaluated in a 3 × 3 Latin square. The 2 trials were repeated using 4 new heifers. Crested wheatgrass was preferred in the first trial, but the Immigrant forage kochia replaced it as most preferred feed in the second set of trials. There was no difference in preference between Otvsel and velvet lupine. Results indicate that Immigrant forage kochia and crested wheatgrass should be selected to evaluate their establishment and palatability in subsequent seeding and field-scale palatability trials in the Scabland region of eastern Washington.

Forage Kochia ( Kochia prostrata ) Increases Nutritional Value, Carrying Capacity, and Livestock Performance on Semiarid Rangelands

Forage Kochia ( <i>Kochia prostrata</i> ) Increases Nutritional Value, Carrying Capacity, and Livestock Performance on Semiarid Rangelands

Potential of Kochia prostrata and Perennial Grasses for Rangeland Restoration in Jordan

Abstract Six varieties of forage kochia ( Kochia prostrata [L.] Schrad.), two Atriplex shrubs native to North America, and four drought-tolerant perennial grass varieties were seeded and evaluated under arid rangeland conditions in Jordan. Varieties were seeded in December 2007 and evaluated in 2008 and 2009 at two sites. Conditions were dry with Qurain receiving 110 mm and 73 mm and Tal Rimah receiving 58 mm and 43 mm of annual precipitation during the winters of 2007/2008 and 2008/2009, respectively. Plants were more abundant and taller ( P P = 0.90) to that observed in 2008 and plant height increased ( P P P

Exotic grass and shrub production evaluation and llama preference on the Bolivian Altiplano

Lack of nutritional forage during the dry season limits llama ( Lama glama) production on the Bolivian Altiplano. Minimal supplementation with stockpiled energy-rich grasses and high-protein shrubs may improve the dry season nutritional status of llamas. The purposes of this study were first, to evaluate forage production on the Altiplano of cold-hardy, drought-resistant plants successful in the Intermountain Western United States and second, the acceptability of these species to llamas. Six species of grass (pubescent wheatgrass [ Agropyron trichophorum], smooth brome [ Bromus inermis], crested wheatgrass [Hycrest] [ Agropyron cristatum × A. desertorum ], weeping lovegrass [ Eragrostis curvula], orchard grass [ Dactylis glomerata], and timothy [ Phleum pratense]) and 6 species of shrubs (black sage [ Artemisia nova], fourwing saltbush [ Atriplex canescens], saltbush [ Atriplex halimus], mountain mahogany [ Cercocarpus montanus], bitterbrush [ Purshia tridentata], and forage kochia [ Kochia prostrata]) were planted at three sites on the Altiplano and evaluated during the dormant season of the following 2 years. Data measuring row fill, biomass, and nutrient concentrations were collected for the grasses. Data measuring percent survival, biomass, and nutrient concentrations were collected for the shrubs. Preference trials including focal animal sampling and instantaneous-scan sampling evaluated the acceptance of these forages by llamas. During the first year, row fill among the grasses ranged from 30–96%. Smooth brome biomass increased from 3427 to 5420 kg dry weight/ha between years ( p ≤ 0.01) and was the most productive grass measured. Crested wheatgrass also increased from 2487 to 4687 kg dry weight/ha ( p ≤ 0.01). The most successful shrubs, forage kochia and fourwing saltbush, survived 75–90%. At one site, fourwing saltbush produced 638 kg dry weight/ha and forage kochia 616 kg dry weight/ha, more ( p ≤ 0.01) than produced at the other sites (91–316 kg dry weight/ha). Among the grasses, the highest CP concentrations were found in crested wheatgrass (9.7%) and orchard grass (9.6%). Weeping lovegrass had lower ( p < 0.01) CP concentration (3.7%). Forage kochia, contained 14.6% CP. Five grasses were similarly preferred receiving between 11 and 18% time grazed. Weeping lovegrass received less ( p ≤ 0.01) at 1–2%. The llamas refused the shrubs completely. Considering biomass and acceptability, orchard grass, pubescent wheatgrass, and smooth brome are likely selections for dry season supplementation.

Relative Cattle Preference of 24 Forage Kochia (Kochia prostrata) Entries and Its Relation to Forage Nutritive Value and Morphological Characteristics

ABSTRACTForage kochia [Kochia prostrata (L.) Schrad.] has been shown to be nutritious fall and winter forage on western U.S. rangelands; however, its utilization by livestock is not well understood. This study compared relative cattle preferences among forage kochia accessions, alfalfa (Medicago sativa L.), and winterfat (Krascheninnikovia spp.), and how they related to nutritional and morphological characteristics. Relative preference was measured as biomass consumed on experimental plots near Promontory, UT, during September of 2002 and 2003. Preference differences (P &lt; 0.01) were found among forage kochia accessions; however, all were consumed to some level, ranging from 71 to 35% of biomass consumed. Traits highly associated with biomass consumed included pregrazing biomass (r = 0.93), phenological maturity (r = −0.85), branch density (r = 0.80), and leafiness (r = 0.70) suggesting that productive, leafy, less mature plants are preferred by cattle. Crude protein, fiber, and digestibility were moderately associated with cattle preference but were not consistent predictors. Overall, we conclude that forage kochia is a palatable shrub for grazing during the fall, with preference and utilization of some entries being comparable to alfalfa and greater than winterfat. Grazing behavior also suggested that forage kochia growing in a mixture with adapted grasses would enhance livestock utilization.

Row Distance Method Sowing of Forage Kochia, Eastern Saltwort and Winterfat

In this study, we used three native range species of eastern saltwort, winterfat and forage Kochia. These species are extremely adapted to dry lands and have high productivity comparison with other forage species. In order to increase range production in poor, dry and sub dry land in the province of Khorasan (Sabzevar) the seeds of these species naturally were sowed. They were sowed individually on rows and mixed of the two by 2 or 3 species on the alternative rows. The research was carried out statistically in Completely Randomized Block Design (CRBD) as a factorial experiment by two factors. The first factor was row distance of seeding (three levels, 50, 75 and 100 cm distance between each row) and the second was kinds of intercropping methods (seven level of individual seeding by three mentioned species and mixed alternative rows of two by 2 and 3 species together) with four replicates (3x7x4). Number of seed was accounted by the number of bushes were germinated or died in each experimental unit. The results showed that maximum abundant of seed germination of all treatments was occurred from late April to late May. Sowing in the row spaces of 50 cm had highly statistically significant production than the ones of 75 and 100 cm spaces. Also, by comparing relative frequency percentage of germinated seeds and relative germinated died seed revealed that individual sowing seed of Salsola orientalis and Eurotia ceratoides, by 50 cm row space in Sabzevar region had better result, respectively, because of lowest mortality of plants and highest productivity of biomass.

Stockpiled Forage Kochia to Maintain Beef Cows During Winter

Extending grazing into the winter, as opposed to feeding of harvested forages, can increase the sustainability of ranching in the western US. This study was conducted to determine the economic value of grazing stockpiled forage kochia ( Kochia prostrata [L.] Scrad.) and crested wheatgrass ( Agropyron desertorum [Fisch. Ex Link] Schultes) during the fall and winter. Changes in cow body weight, body condition score, and ultrasound backfat were compared for late-gestation cows grazing forage kochia–crested wheatgrass pastures vs. those fed alfalfa ( Medicago sativa L.) hay in drylot. The study was conducted from early November to late January for 2 consecutive years near Promontory, Utah. Forage availability and nutritional quality were monitored throughout the experiment. Cows grazing stockpiled forages did not receive any protein or energy supplements. Forage kochia comprised approximately 70% of available forage, with November crude protein content of 116 and 76 g·kg −1 in years 1 and 2, respectively. Nutritional quality declined throughout the season, presumably mostly because of removal of higher-quality forage by preferential grazing as opposed to weathering. Averaged over years, cows grazing forage kochia–grass gained body weight (19 kg), increased in body condition (0.3 points), and maintained backfat thickness, finishing well within the range considered optimum for onset of calving and return to estrus . Pasture- vs. drylot-fed cows did not differ with regard to changes in body weight or body condition score. Both treatments increased backfat in year 1, when initial backfat was less than 0.5 cm, but both treatments resulted in loss of backfat in year 2, when initial backfat was greater than 1.0 cm. Grazing was more economical, costing $0.24·cow −1 ·d −1 less than feeding alfalfa hay in drylot. Forage kochia can be used on western rangelands to extend grazing into the fall and winter, thereby improving the profitability of beef production. Extender el apacentamiento hasta el invierno, como estrategia opuesta a la alimentación con forrajes cultivados, puede incrementar la sostenibilidad de las operaciones ganaderas del oeste de Estados Unidos. Este estudio se condujo para determinar el valor económico de apacentar forraje acumulado en pie de “Kochia” ( Kochia prostrata [L.] Scrad.) y “crested wheatgrass” ( Agropyron desertorum [Fisch. Ex Link] Schultes) durante el otoño e invierno. Cambios en el peso corporal, la condición corporal y grasa del lomo medida con ultrasonido fueron comparados entre vacas en estado final de gestación apacentando praderas de “Kochia”–“Crested wheatgrass” versus vacas alimentadas en corral con heno de “Alfalfa” ( Medicago sativa L.). El estudio se llevo a cabo cerca de Promontory, Utah de inicios de Noviembre a fines de Enero durante dos años consecutivos. La disponibilidad de forraje y la calidad nutricional fueron monitoreadas a lo largo del experimento. Las vacas apacentando los forrajes acumulados en pie no recibieron ningún suplemento ni proteico ni energético. El forraje de “Kochia” aportó aproximadamente el 70% del forraje disponible, con un contenido de proteína cruda en Noviembre de 116 y 76 g·kg −1 en el año 1 y 2, respectivamente. La calidad nutricional disminuyó a través de la estación de apacentamiento, presumiblemente debido en gran parte a la remoción de forraje de alta calidad por el apacentamiento preferencial como opuesto al intemperismo. Promediado a través de los años, las vacas apacentando “Kochia-zacate” ganaron peso corporal (19 kg), incrementaron su condición corporal (0.3 puntos) y mantuvieron el espesor de la grasa del lomo, terminando bien dentro del rango considerado como optimo para el inicio de la época de pariciones y regresar al estro. Las vacas apacentando las praderas versus las alimentadas en estabulación no difirieron en los cambios de peso o condición corporal. Ambos tratamientos incrementaron la grasa del lomo en el primer año, cuando la grasa inicial fue menos de 0.5 cm, pero en el segundo año, ambos tratamientos resultaron en perdida de grasa del lomo cuando la grasa inicial del lomo fue mayor a 1 cm. El apacentamiento fue más económico, costando $0.24·vaca −1 ·día −1 menos que la alimentación con alfalfa en corral. El forraje de “Kochia” puede ser utilizado en los pastizales del oeste para extender el apacentamiento hasta otoño e invierno, por lo tanto mejorando la rentabilidad de la producción de carne.

Stockpiled Forage Kochia to Maintain Beef Cows During Winter

Extending grazing into the winter, as opposed to feeding of harvested forages, can increase the sustainability of ranching in the western US. This study was conducted to determine the economic value of grazing stockpiled forage kochia (Kochia prostrata [L.] Scrad.) and crested wheatgrass (Agropyron desertorum [Fisch. Ex Link] Schultes) during the fall and winter. Changes in cow body weight, body condition score, and ultrasound backfat were compared for late-gestation cows grazing forage kochia- crested wheatgrass pastures vs. those fed alfalfa (Medicago sativa L.) hay in drylot. The study was conducted from early November to late January for 2 consecutive years near Promontory, Utah. Forage availability and nutritional quality were monitored throughout the experiment. Cows grazing stockpiled forages did not receive any protein or energy supplements. Forage kochia comprised approximately 70% of available forage, with November crude protein content of 116 and 76 g kg-1 in years 1 and 2, respectively. Nutritional quality declined throughout the season, presumably mostly because of removal of higher-quality forage by preferential grazing as opposed to weathering. Averaged over years, cows grazing forage kochia-grass gained body weight (19 kg), increased in body condition (0.3 points), and maintained backfat thickness, finishing well within the range considered optimum for onset of calving and return to estrus. Pasture- vs. drylot-fed cows did not differ with regard to changes in body weight or body condition score. Both treatments increased backfat in year 1, when initial backfat was less than 0.5 cm, but both treatments resulted in loss of backfat in year 2, when initial backfat was greater than 1.0 cm. Grazing was more economical, costing 0.24 cow-1 d-1 less than feeding alfalfa hay in drylot. Forage kochia can be used on western rangelands to extend grazing into the fall and winter, thereby improving the profitability of beef production.

Relationships among 3Kochiaspecies based on PCR-generated molecular sequences and molecular cytogenetics

Forage kochia (Kochia prostrata ssp. virescens 'Immigrant' is native to the arid and semiarid regions of central Eurasia. It was introduced into the United States in 1966 as PI 314929 and released as a perennial forage shrub in 1984. Kochia americana is a perennial native to the United States, whereas Kochia scorparia is an introduced annual species that became a weed. To assess both the breeding potential and the possibility of genetic contamination, relationships among the 3 Kochia species were analyzed using random amplified polymorphic DNA (RAPD) markers, sequence tagged site (STS) marker sequences of the chloroplast NADH dehydrogenase gene (ndhF), genomic in situ hybridization (GISH), and multicolor fluorescence in situ hybridization (MC-FISH). Seventy decamer random primers yielded 458 polymorphic bands from 9 plants of K. americana, 20 plants of K. prostrata, and 7 plants of K. scoparia. Fifty-four and 55 species-specific RAPD markers were identified for K. americana and K. prostrata, whereas 80 RAPD markers were specific to K. scoparia. Based on the presence or absence of informative RAPD markers, the 3 species always grouped into 3 distinct clusters in a NTSYSpc2.01b-generated dendrogram. The same relationships were found among the 3 Kochia species based on ndhF DNA sequence divergence. Using a set of 7 STS markers that can identify each Kochia species, we did not find a single interspecific hybrid from artificial hybridizations among the 3 Kochia species. In GISH studies, chromosomes of 1 species fluoresced in green only when they were probed by genomic DNA of the same species. Cross-hybridization by genomic DNA of another species was not observed. In FISH studies using pTa71 (for 18S-5.8S-26S rDNAs) and pScT7 (for 5S rDNA) as probes, there were 1, 1 and 3 pTa71 sites and 2, 1, and 1 pScT7 sites in each haplome of K. prostrata, K. americana, and K. scoparia, respectively. It is concluded that these 3 Kochia species are so genomically distinct that gene introgression among them would be extremely rare.

Forage Kochia—Uzbekistan’s Desert Alfalfa: Forage kochia germplasm from Uzbekistan may increase fall and winter grazing and habitat for livestock and wildlife on western rangelands

Forage kochia germplasm from Uzbekistan may increase fall and winter grazing and habitat for livestock and wildlife on western rangelands. DOI:10.2458/azu_rangelands_v27i1_waldron

Forage Kochia—Uzbekistan's Desert Alfalfa

Forage kochia germplasm from Uzbekistan may increase fall and winter grazing and habitat for livestock and wildlife on western rangelands.

Nutritional and Seed Responses of Forage Kochia to Ruminal Incubation

Forage kochia may be a complimentary forage to most dormant cool-season grasses in the Intermountain West. DOI:10.2458/azu_rangelands_v26i1_Schauer

Nutritional and Seed Responses of Forage Kochia to Ruminal Incubation

Forage kochia may be a complimentary forage to most dormant cool-season grasses in the Intermountain West.

'Immigrant' Forage Kochia Seed Viability as Impacted by Storage Methods

'Immigrant' forage kochia (Kochia prostrata (L.) Schrad.) is a valuable introduced subshrub, often used in reclamation plantings and seedings on western rangelands. Seedling establishment is best from fresh seed; however, many users plant stored seed and experience poor seeding success. One cause for failure is loss of seed viability in storage. Forage kochia seed was harvested on 4 dates in fall 1996 from 2 sites (wildland and irrigated) and tested for viability when fresh and after storage treatments. Storage treatments included low and high seed water contents (2-6% and 12-16%), cold and warm storage temperatures (2 degrees and 25 degrees C), and duration of storage (4, 8, and 12 months). Mature, highly viable forage kochia seed remains viable in storage longer than seed harvested prematurely. Low seed water content (2-6%) is essential to preserving maximum seed viability. Storing seed at a cold temperature (2 degrees C) is also helpful in maintaining viability. DOI:10.2458/azu_jrm_v54i4_stewart

Forage Kochia Seed Germination Response to Storage Time and Temperature

The Eurasian low-shrub, forage kochia [Kochia prostrata (L.) Shad.], was introduced into western North America for use in restoration of severely disturbed landscapes in arid and semiarid environments. Seed mature in late fall and are short-lived in typical warehouse conditions. In a preliminary, cold-temperature experiment (2 degrees C) using 3-month-old seed from 16 forage kochia accessions, mean germination time, expressed as days to 50% germination, varied from 4 to 88 days. Follow up experiments using seed of 5 accessions tested the effects of storage time and temperature on seed viability and mean germination time and related this to field planting success. Sub-samples were air-dried and stored in plastic bags in a freezer, cold room, and lab (-15, 2, and 20 degrees C respectively). A fourth set of subsamples was stored in a shed with no temperature control (simulated warehouse storage). Seed were tested fresh and retested after 4, 8, 12, 24, and 36 months of storage. Mean viability decreased from 77% (range 66 to 93%) for recently harvested seed, to 24 and 8% for lab- and shed-stored seed, after 36 months of storage. No significant change in viability was observed for cold room- and freezer-stored seed. Across all accessions, cold temperature mean germination time (MGT) for recently harvested seed was 73 days (range 51 to 109 days). For each accession, germination occurred primarily over a 70 day period. Mean germination time decreased as storage time increased for lab- and shed-stored seed, varied unpredictably for cold room-stored seed, and remained unchanged for freezer-stored seed. Field germination using 1- and 2-year old lab- and shed-stored seed was significantly faster than that of same-aged cold room- and freezer-stored seed. The number of live seedlings 4 months after planting for cold room- and freezer-stored seed was 10-fold or greater than that of lab- and shed-stored seed. Thus a delayed, asynchronous cold-temperature germination pattern appears to be adaptive for forage kochia establishment. Cold, dry storage prevents loss of seed viability and preserves this desirable germination pattern. DOI:10.2458/azu_jrm_v54i3_kitchen

Forage kochia seed germination response to storage time and temperature

The Eurasian low-shrub, forage kochia [Kochia prostrata (L.) Shad.], was introduced into western North America for use in restoration of severely disturbed landscapes in arid and semiarid environments. Seed mature in late fall and are short-lived in typical warehouse conditions. In a preliminary, cold-temperature experiment (2 degrees C) using 3-month-old seed from 16 forage kochia accessions, mean germination time, expressed as days to 50% germination, varied from 4 to 88 days. Follow up experiments using seed of 5 accessions tested the effects of storage time and temperature on seed viability and mean germination time and related this to field planting success. Sub-samples were air-dried and stored in plastic bags in a freezer, cold room, and lab (-15, 2, and 20 degrees C respectively). A fourth set of subsamples was stored in a shed with no temperature control (simulated warehouse storage). Seed were tested fresh and retested after 4, 8, 12, 24, and 36 months of storage. Mean viability decreased from 77% (range 66 to 93%) for recently harvested seed, to 24 and 8% for lab- and shed-stored seed, after 36 months of storage. No significant change in viability was observed for cold room- and freezer-stored seed. Across all accessions, cold temperature mean germination time (MGT) for recently harvested seed was 73 days (range 51 to 109 days). For each accession, germination occurred primarily over a 70 day period. Mean germination time decreased as storage time increased for lab- and shed-stored seed, varied unpredictably for cold room-stored seed, and remained unchanged for freezer-stored seed. Field germination using 1- and 2-year old lab- and shed-stored seed was significantly faster than that of same-aged cold room- and freezer-stored seed. The number of live seedlings 4 months after planting for cold room- and freezer-stored seed was 10-fold or greater than that of lab- and shed-stored seed. Thus a delayed, asynchronous cold-temperature germination pattern appears to be adaptive for forage kochia establishment. Cold, dry storage prevents loss of seed viability and preserves this desirable germination pattern.

Immigrant' forage kochia seed viability as impacted by storage methods

Immigrant' forage kochia (Kochia prostrata (L.) Schrad.) is a valuable introduced subshrub, often used in reclamation plantings and seedings on western rangelands. Seedling establishment is best from fresh seed; however, many users plant stored seed and experience poor seeding success. One cause for failure is loss of seed viability in storage. Forage kochia seed was harvested on 4 dates in fall 1996 from 2 sites (wildland and irrigated) and tested for viability when fresh and after storage treatments. Storage treatments included low and high seed water contents (2-6% and 12-16%), cold and warm storage temperatures (2 degrees and 25 degrees C), and duration of storage (4, 8, and 12 months). Mature, highly viable forage kochia seed remains viable in storage longer than seed harvested prematurely. Low seed water content (2-6%) is essential to preserving maximum seed viability. Storing seed at a cold temperature (2 degrees C) is also helpful in maintaining viability.

Adaptation of forage Kochia accessions across an environmental gradient in rush valley, Utah

Forage kochia (Kochia prostrata) is native to Eurasia. It is a useful plant for reclamation in semiarid and arid regions with mineral soils. Fourteen accessions representing both forage kochia subspecies and all known polyploid levels (2x‐6x) were tested for adaptation over an environmental gradient represented by three study sites differing in native plant composition, average annual precipitation, and soil type. Plants were established by transplanting in 1988 and 1989 and evaluated for growth (height, crown diameter, biomass) parameters and for stand establishment, growth habit, uniformity of growth, vigor, cover, seed production, survival, and recruitment from 1990 to 1992. Soil characteristics (pH, SAR, salinity, sand, clay, silt, organic matter, NO3‐N, Ca, Na, Mg, P, K, CaCO3, and effective rooting depth) were measured at each study site. Two hypotheses were addressed. First, it was confirmed that forage kochia accessions in general perform better in lighter textured soils and at higher precipitatio...

Reed canarygrass survival under cyclic inundation: J. S. Rice & B. W. Pinkerton, Journal of Soil & Water Conservation, 48(2), 1993, pp 132–135

Gardner’s saltbush ecosystems are increasingly being invaded by halogeton (Halogeton glomeratus [M. Bieb.] C.A. Mey.), an annual halophyte that increases soil surface salinity and reduces plant biodiversity. Thus, a study was established in the Flaming Gorge National Recreation Area within the lower Green River Basin of Wyoming to evaluate the potential for rehabilitating halogeton-dominated Gardner’s saltbush ecosystems with forage kochia (Bassia prostrata [L.] A.J. Scott), Russian wildrye (Psathyrostachys juncea [Fisch.] Nevski), tall wheatgrass (Thinopyrum ponticum [Podp.] Z.-W. Liu & R.-C. Wang), Indian ricegrass (Achnatherum hymenoides [Roem. & Schult.] Barkworth), and Gardner’s saltbush (Atriplex garneri [Moq.] D. Dietr.). A seeding evaluation, with and without prior disking, was conducted to determine ability of these species to establish. A transplant evaluation determined the effect of established plants on halogeton frequency at four 10-cm intervals (10–20, 20–30, 30–40, and 40–50 cm) distal from transplants. Gardner’s saltbush, tall wheatgrass, and Indian ricegrass did not establish in the seeded study or persist beyond the first year in transplant study. In contrast, Russian wildrye and forage kochia established and persisted, with Russian wildrye establishment higher (P = 0.05) in the disked treatment compared with no-till (4.5 and 1.7 plants m− 2, respectively) and no-till favoring (P = 0.05) forage kochia establishment (2.3 and 0.8 plants m− 2, respectively). Transplants of these two species reduced halogeton frequency by 52% relative to the control. Moreover, this interference of halogeton establishment by Russian wildrye and forage kochia had extended to 50 cm distal from transplant by the second year of the study. By the third year (2014), transplant survival and halogeton frequency were highly correlated (r = − 0.61, P = 0.0001), indicating the importance of plant persistence. Results indicate that Russian wildrye and forage kochia can establish and reduce halogeton frequency, thereby providing an opportunity for rehabilitation of halogeton-invaded areas.

Environmental Influences on Germination of Utricles and Seedling Establishment of 'Immigrant' Forage Kochia

Estrblishment of forage kochia (Kochiuprostruta subsp. virestens) stands from planting utricles has been erratic in the northern Great Basin. This study evaluated the effect of different seedbed environments varied by planting date on germination of utricles and seedling establishment. Utricles harvested in 1986 were planted on tilled seedbeds in late fall, winter, early and late spring 1986-87, and late fall, winter, and early spring 1987-88. Soils are fine-loamy, mixed, mesic, Xerollic Haplargids underlain by coarse gravel at a depth of 1.5 m. Utricles were broadcast at 400 pure live utricles/m* in 2 by 2-m plots replicated 5 times. Additionally, nylon bags containing utricles were placed on the soil surface during planting, and on each subsequent planting date, bags of utricles were retrieved for germination trials. Seedling establishment was improved 85% (p<O.OS) when utricles were planted in late fall and winter compared to spring of both 1987 and 1988. Utricles imbibed moisture when incubated in the tield from late fall to winter and late fall to early spring 1986-87. When collected in winter 1987, imbibed utricles germinated 7 to 12 days faster (p<O.O5) than dry controls, and those collected in early spring germinated 4 to 7 days faster @<0.05) than controls. Total germination of utricles declined 9 to 2% with an additional year of storage in the laboratory. Utricles incubated in the field from late fall to winter and late fall to early spring 1987-88 germinated about 1.5 days faster @<0.05) than controls when collected in winter and early spring 1988. These findings show why better seedling establishment can be expected from planting freshly harvested forage kochia utricles in late fall and winter before the soil surface begins to dry than in early and late spring in the northern sagebrush (Artemisia) steppe.