Restoration in dryland ecosystems is hindered by low establishment of seeded species. As such, evaluations of current seeding methods are critical to understanding limitations and barriers to seeding success. Drill seeding is perceived as an optimal seeding strategy in many dryland ecosystems, but broadcast seeding is more commonly used as a seeding method due to physical and logistical constraints. For example, broadcast seeding may be conducted by aerial drops where other methods are limited by topography or obstructive features in the landscape. Few studies have quantified the differences between drill and broadcast seeding through space and time. We compare 2‐year recruitment of emergent Pseudoroegneria spicata (bluebunch wheatgrass) seedlings in the sagebrush steppe biome for drill versus broadcast seeding methods across three seeding years, three landscape aspects and two soil types using a 95% confidence interval approach to avoid the penalty of multiplicity. We found drill seeding had 2.7 times greater recruitment of seedlings after 2 years compared with broadcast seeding. However, differences were highly subject to seeding year, aspect and soil type, likely because of soil moisture and temperature variations. Drill seeding had an advantage on clay soils with flat and north aspects (10.1 and 4.6 times greater for drill than broadcast seeding, respectively). In most conditions, drill seeding had greater recruitment than broadcast seeding, though in 2014 on south aspects broadcast seeding had 2.7 times greater recruitment than drill seeding. The results of this study demonstrate a need for restoration plans that account for spatiotemporal variation in seeding success.

Rapid Ohia Death is a major concern for the viability of ohia (Metrosideros polymorpha) in Hawaii and has led to restrictions on log movement. The potential for using disodium octaborate tetrahydrate (DOT) and didecyl dimethyl ammonium chloride (DDAC) dip diffusion treatments to control the two causal fungi (Ceratocystis lukuohia and Ceratocystis huliohia) was investigated. A 10 percent boric acid equivalent dip diffusion treatment killed the pathogens in 0.5-cm-thick disks obtained from 4.0- to 5.0-cm-diameter limbs of naturally colonized trees. DOT tended to diffuse more consistently in 50- to 60-cm-long bolts of small (4.0 to 9.0 cm) and large (9.1 to 17.0 cm) diameter healthy ohia compared with those bolts naturally infected by C. lukuohia. Diffusion periods longer than 6 weeks resulted in deeper penetration. Immersion (24 h) of logs (1.3 m long; 9 to 17 cm diameter) from C. lukuohia artificially inoculated trees in two forest locations in a 15 percent DOT/1 percent DDAC solution and storage for 10 weeks before evaluation resulted in incomplete elimination of the pathogen and lower boron concentrations in the inner sapwood than outer. Further investigations are needed to explore using either higher boron concentrations or longer diffusion periods to deliver fungicidal concentrations of boron deeper within the wood matrix.

Recent efforts have been made to develop hot-air-dried chips as a value-added product for persimmon fruit (Diospyros kaki). However, the long-term quality of this product and its dependence on processing conditions and packaging type have not yet been explored. Hence, in this work, chips were prepared from “Hachiya” persimmon fruit in 2 ways: 2 mm thickness fruit slices, hot-air-dried for 5 hours (Preparation 2–5), and 6 mm slices, dried for 10 hours (Preparation 6–10). The dried chips were then packaged into 2 bag types (plastic zip-top and metallized polyethylene terephthalate (Met-PET) with desiccant packets), stored under ambient conditions, and sampled for moisture-related, microbial, texture, and chemical quality traits throughout the 1-year storage study. It was found that–with the exception of a marked decrease in ascorbic acid (vitamin C)—all 4 Preparation/Packaging combinations yielded products that maintained acceptable color, microbial, nutritional, and textural quality throughout the entire study. Compared to Preparation 2–5 chips, Preparation 6–10 chips generally had lower contents of healthy nutrients—antioxidant compounds, ascorbic acid, and carotenoids. Evidence of invertase activity was found for Preparation 6–10 chips but not for Preparation 2–5 chips. For both preparations, the contents of ascorbic acid and carotenoids experienced time-dependent decreases. Plastic zip-top bags and Met-PET bags with desiccant packets performed equally well as packaging for most of the quality metrics tracked during this study. Overall, this work has demonstrated that hot-air-drying of persimmon slices is a promising approach to create a value-added product with at least one year of shelf-life.

Multiple sclerosis (MS) is a neurologic autoimmune disease, which is the leading cause of nontraumatic neurologic disability in young adults in United States and Europe. n-3 polyunsaturated fatty acids (PUFA) are reported to mitigate severity of this disease. Recent studies suggest that phospholipid (PL) form of dietary n-3 PUFA may lead to their higher tissue accretion than triacylglycerol (TAG) form. We compared efficacy of PL-docosahexaenoic acid (22:6n-3) (DHA) and TAG-DHA on onset and severity of experimental autoimmune encephalomyelitis (EAE) in a mouse model of MS. Female mice were fed low alpha-linolenic acid (18:3n-3) (ALA) diet (control) for 2 weeks and then fed either control, 0.3%, or 1.0% DHA (PL or TAG) for 4 weeks pre-EAE induction and 4 weeks post-EAE induction. The brain and spinal cord n-6:n-3 ratio was significantly lower in all mice fed DHA compared to control. EAE onset was delayed in mice fed both DHA forms and concentrations, except for 1% TAG-DHA. The inverse association between the EAE score and the brain DHA concentration was nonsignificant at the end of the study (p = 0.08). Daily EAE scores of mice fed different DHA diets did not differ from control, however, the score of all DHA groups combined during days 9-16 was lower (p = 0.028) compared to the control. During days 17-22, the EAE score trended lower in 0.3% TAG-DHA and during days 23-28, the EAE score trended lower in both PL-DHA groups than those in all other groups. These findings suggest that TAG-DHA may be more effective than PL-DHA in the early phases of EAE, and in the final outcome, PL-DHA may be more effective than TAG-DHA.

Core Ideas Vineyard management practices create spatial heterogeneity in CO2 efflux and SOM content. Soil C dynamics are influenced by water availability rather than temperature in comparatively warm Mediterranean climates. Soil tillage, organic amendments, cover crops, irrigation and precipitation stimulate CO2 efflux. To characterize the effect of precipitation events, management practices, and soil type on vineyard carbon (C) dynamics, we monitored CO 2 emissions and labile C pools from nine vineyards in Lodi Wine Grape District, California, from April 2011 to December 2012. These commercial vineyards are replicates of three soil series (Redding, San Joaquin, and Tokay), representing a spectrum of soil texture and degree of soil development. We hypothesized that soil characteristics would influence the magnitude of CO 2 efflux occurring in response to precipitation and management events in a Mediterranean climate. During each field visit—bimonthly (April–October) and monthly (November–March)—we measured CO 2 , soil temperature, and gravimetric water content (GWC) from vine and intervine (alleys) rows. Monthly, we collected soil samples for dissolved organic C (DOC), which tended to be greater in the alleys of San Joaquin and Redding than Tokay in summer but decreased after the onset of precipitation. In mid‐May and mid‐October 2012, CO 2 efflux was higher in Tokay than in San Joaquin or Redding. Carbon dioxide efflux across all soils increased as a result of seasonal management practices (i.e., tillage and mowing of cover crops). Management practices distinguished soil DOC between vine rows and alleys from June to October 2012. Soil type or clay content influenced CO 2 efflux across these vineyards, as did GWC and soil temperature. This 20‐mo study indicated that CO 2 efflux responded to soil disturbance from management practices, precipitation, and irrigation.

Recent studies suggest that dietary krill oil leads to higher omega-3 polyunsaturated fatty acids (n-3 PUFA) tissue accretion compared to fish oil because the former is rich in n-3 PUFA esterified as phospholipids (PL), while n-3 PUFA in fish oil are primarily esterified as triacylglycerols (TAG). Tissue accretion of the same dietary concentrations of PL- and TAG-docosahexaenoic acid (22:6n-3) (DHA) has not been compared and was the focus of this study. Mice (n = 12/group) were fed either a control diet or one of six DHA (1%, 2%, or 4%) as PL-DHA or TAG-DHA diets for 4 weeks. Compared with the control, DHA concentration in liver, adipose tissue (AT), heart, and eye, but not brain, were significantly higher in mice consuming either PL- or TAG-DHA, but there was no difference in DHA concentration in all tissues between the PL- or TAG-DHA forms. Consumption of PL- and TAG-DHA at all concentrations significantly elevated eicosapentaenoic acid (20:5n-3) (EPA) in all tissues when compared with the control group, while docoshexapentaenoic acid (22:5n-6) (DPA) was significantly higher in all tissues except for the eye and heart. Both DHA forms lowered total omega-6 polyunsaturated fatty acids (n-6 PUFA) in all tissues and total monounsaturated fatty acids (MUFA) in the liver and AT; total saturated fatty acid (SFA) were lowered in the liver but elevated in the AT. An increase in the DHA dose, independent of DHA forms, significantly lowered n-6 PUFA and significantly elevated n-3 PUFA concentration in all tissues. Our results do not support the claim that the PL form of n-3 PUFA leads to higher n-3 PUFA tissue accretion than their TAG form.

Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV) and transmitted by Polymyxa betae , is considered the most important disease of sugar beet and has spread to almost all production areas of the world. The most efficient way to control this soil-borne disease is through the cultivation of rhizomania-resistant varieties, which has proven successful since the 1980s. In the 2002–2003 season, sugar beet fields in the Imperial Valley, California, planted with a resistant commercial variety were observed with severe rhizomania symptoms suggesting resistance conferred by the most widely deployed gene, Rz1 , was compromised. BNYVV isolates were identified to which all resistant check varieties became infected and tested positive for the virus (RB-BNYVV, Rz1 -resistance breaking strain of Beet necrotic yellow vein virus ). For continuing development of BNYVV and RB-BNYVV resistant germplasm, a highly important reservoir of resistance factors is the Beta vulgaris subsp. maritima (BVM) accession collection. We evaluated 404 BVM accessions under BNYVV and RB-BNYVV field and greenhouse conditions to identify and select rhizomania resistant accessions useful for sugar beet germplasm improvement. Accessions from Denmark, Ireland, and Portugal showed the highest level of rhizomania resistance as characterized by foliar yellowing due to rhizomania, rhizomania disease index, and percent resistant beets. The low bolting tendency of Denmark and Ireland accessions suggest these for pre-breeding donor material.

To assess the potential to suppress Mediterranean fruit fly, Ceratitis capitata (Wiedemann; Diptera: Tephritidae), via mass trapping with Trimedlure (TML), we compared fly catch (as catch per trap per time period) provided by either a novel, solid, triple-lure dispenser with TML, methyl eugenol (ME), and raspberry ketone (RK) (TMR) or solid TML plugs, both without insecticides, in addition to Biolure bait stations. Work was done in a coffee plantation that had a dense C. capitata population. Three treatments were compared: 1) TMR or TML (50 traps per ha), 2) Biolure (50 traps per ha), 3) TML (25 per ha) or TMR (25 per ha) + Biolure (25 per ha), and 4) an untreated control. During coffee season, based on C. capitata captures (mean flies per trap per wk) inside plastic McPhail traps, all treatments were significantly different than the control: Biolure (9.57) = TMR (11.28) = Biolure +TMR (13.50) < Control (36.06 flies/trap/wk). During non-coffee season, all treatments were significantly different than the control and TML was significantly lower than Biolure (wax matrix bait stations): TML (0.95) < Biolure (1.43) = Biolure +TML (1.77) < Control (2.81 flies/trap/wk). Surprisingly, captures were not lower in plots treated with combinations of Biolure + TMR or TML, compared to individual plots with Biolure or TML or TMR alone. Mass trapping with either TML or TMR dispensers deserves further study as a component of Integrated Pest Management programs for C. capitata in Hawaii and may have global potential for management of C. capitata.

Cold tolerance studies were conducted with the egg and larval stages of Mediterranean fruit fly, Ceratitis capitata (Wiedemann) and melon fly, Zeugodacus (Bactrocera) cucurbitae (Coquillett) in Navel oranges to determine whether quarantine cold treatments approved for C. capitata might also be effective against Z. cucurbitae. Navel orange is a good host for C. capitata and a poor host for Z. cucurbitae, and therefore, artificial infestation of fruit was used to facilitate comparisons. Laboratory-reared eggs and larvae were inserted in the center of Navel oranges, placed in cold storage chambers at 1.5-2.0°C for 1, 2, 4, 6, 8, 10, 12, or 14 d, then removed, and evaluated for egg hatch or larval survival. Time-response data were analyzed using linear mixed-effects models, probit analysis, and visual inspection of survivorship graphs. C. capitata eggs were significantly more cold tolerant than Z. cucurbitae eggs, and Z. cucurbitae larvae were generally more cold tolerant than C. capitata larvae. C. capitata eggs and Z. cucurbitae second instar larvae were the most cold-tolerant life stages, and they were not significantly different from each other. Results suggest that cold treatment at ≤1.5°C for a minimum of 14 d would be sufficient to achieve disinfestation of C. capitata and Z. cucurbitae. The inherent cold tolerance in Z. cucurbitae is equal to or higher than that of C. capitata, and therefore, cold treatment protocols developed for C. capitata may not always be effective against Z. cucurbitae.

trans 10,cis 12-CLA has been reported to alter fatty acid composition in several non-neurological tissues, but its effects are less known in neurological tissues. Therefore, the purpose of this study was to determine if CLA supplementation would alter brain and eye fatty acid composition and if those changes could be prevented by concomitant supplementation with docosahexaenoic acid (DHA; 22:6n3) or eicosapentaenoic acid (EPA; 20:5n3). Eight-week-old, pathogen-free C57BL/6N female mice (n = 6/group) were fed either the control diet or diets containing 0.5% (w/w) t10,c12-CLA in the presence or absence of either 1.5% DHA or 1.5% EPA for 8 weeks. CLA concentration was significantly (P < 0.05) greater in the eye but not in the brain lipids of the CLA group when compared with the control group. The sums of saturated, monounsaturated, polyunsaturated fatty acids, and n3:n6 ratio did not differ between these two groups for both tissues. The n3:n6 ratio and concentrations of 20:5n3 and 22:5n3 were significantly greater, and those of 20:4n6, 22:4n6, and 22:5n6 were lesser in the CLA + DHA and CLA + EPA groups than in the control and CLA groups for either tissue. DHA concentration was higher in the CLA + DHA group only but not in the CLA + EPA group when compared with the CLA group for both tissues. The dietary fatty acids generally induced similar changes in brain and eye fatty acid concentration and at the concentrations used both DHA and EPA fed individually with CLA were more potent than CLA alone in altering the tissue fatty acid concentration.

Core Ideas Alleys have greater soil C and N pools than vine rows. Soil N 2 O emissions increase in response to precipitation, fertigation, and irrigation. Path analysis revealed that vineyard zone and soil texture influence N 2 O emissions. Path analysis revealed that GWC influences N 2 O emissions. To evaluate the effect of precipitation events, management practices, and soil type in wine grape ( Vitis vinifera L. ssp. vinifera ) vineyard systems and provide data for greenhouse gas (GHG) emissions calculators, we monitored nine vineyards in the Lodi wine grape district, California, from April 2011 to December 2012. These commercial vineyards exist on three soil series (Redding, San Joaquin, and Tokay), representing a spectrum of soil textures and degrees of soil development. We hypothesized that soil characteristics would be a dominating factor affecting GHG fluxes, but the magnitude of fluxes would be influenced by precipitation and management events. We measured N 2 O fluxes, soil NO 3 –N and NH 4 –N, and gravimetric water content (GWC) from vine and intervine (alleys) rows bimonthly (April–October) and monthly (November–March). Monthly, we collected soil samples for dissolved organic C (DOC) and dissolved organic N (DON) determination. Path analysis revealed that the effects of soil type and vineyard zone on N 2 O emissions were influenced by soil texture (i.e., gravel and clay contents) but that this effect was mediated by GWC through soil temperature and soil inorganic N content. Management practices such as irrigation, fertigation, cover cropping, and tillage affected differences between vine rows and alleys for soil inorganic pools, DOC, and DON from June to October 2012. This 20‐mo study indicated that precipitation events strongly influenced N 2 O fluxes.

Diets containing high n-3 polyunsaturated fatty acids (PUFA) decrease inflammation and the incidence of chronic diseases including cardiovascular disease and nonalcoholic fatty liver disease while trans-fatty acids (TFA) intake increases the incidence of these conditions. Some health benefits of n-3 PUFA are mediated through the impact of their oxygenated metabolites, i.e. oxylipins. The TFA, trans-10, cis-12-conjugated linoleic acid (CLA; 18:2n-6) is associated with adipose tissue (AT) inflammation, oxidative stress, and wasting. We examined the impact of a 4-week feeding of 0, 0.5, and 1.5% docosahexaenoic acid (DHA; 22:6n-3) in the presence and absence of 0.5% CLA on AT oxylipin profiles in female C57BL/6N mice. Esterified oxylipins in AT derived from linoleic acid (LNA), alpha-linolenic acid (ALA), arachidonic acid (ARA), eicosapentaenoic acid (EPA), DHA, and putative from CLA were quantified. CLA containing diets reduced AT mass by ~62%. Compared with the control diet, the DHA diet elevated concentrations of EPA-and DHA-derived alcohols and epoxides and LNA-derived alcohols, reduced ARA-derived alcohols, ketones, epoxides, and 6-keto-prostaglandin (PG) F1α (P < 0.05), and had mixed effects on ALA-derived alcohols. Dietary CLA lowered EPA-, DHA-, and ALA-derived epoxides, ARA-derived ketones and epoxides, and ALA-derived alcohols. While dietary CLA induced variable effects in EPA-, DHA-, and LNA-derived alcohols and LNA-derived ketones, it elevated ARA-derived alcohols and PGF1α, PGF2α, and F2-isoprostanes. DHA counteracted CLA-induced effects in 67, 57, 43, and 29% of total DHA-, ARA-, EPA-, and ALA-derived oxylipins, respectively. Thus, CLA elevated proinflammatory oxylipins while DHA increased anti-inflammatory oxylipins and diminished concentration of CLA-induced pro-inflammatory oxylipins in AT.

Modified atmosphere packaging (MAP) creates a low-oxygen (O2) environment that can increase the shelf life of fresh produce by decreasing respiration and the growth of pathogens. Low oxygen may also increase insect tolerance to irradiation (IR), and the use of MAP with products treated by IR to control quarantine pests before export may inadvertently compromise treatment efficacy. Spotted wing drosophila, Drosophila suzukii Matsumura (Diptera: Drosophilidae) is a quarantine pest of stone and small fruits and a potential target for postharvest IR treatment. The effect of low oxygen generated by MAP at ambient temperatures on the radiation tolerance of D. suzukii infesting sweet cherries was examined. Early pupal stage D. suzukii were inserted into ripe sweet cherries and treated by 1) MAP + IR, 2) IR alone, 3) MAP alone, or 4) no MAP and no IR and held for adult emergence. Three types of commercially available MAP products were tested that produced different oxygen concentrations between 3 and 15%, and a sublethal radiation dose (60 Gy) was used to allow comparisons between the treatments. Xtend PP61 bags (3.2-4.8% O2), Xtend PP71 bags (5.4-8.6% O2), and Xtend PP53 bags (13.6-15.4% O2) did not enhance survivorship to the adult stage in D. suzukii pupae irradiated at 60 Gy in sweet cherries. MAP use should not compromise phytosanitary IR treatment against D. suzukii in exported sweet cherries or other fruit.

Degradation models for multilure fruit fly trap dispensers were analyzed to determine their potential for use in large California detection programs. Solid three-component male lure TMR (trimedlure [TML], methyl eugenol [ME], raspberry ketone [RK]) dispensers impregnated with DDVP (2, 2-dichlorovinyl dimethyl phosphate) insecticide placed inside Jackson traps were weathered during summer (8 wk) and winter (12 wk) in five citrus-growing areas. Additionally, TMR wafers without DDVP, but with an insecticidal strip, were compared to TMR dispensers with DDVP. Weathered dispensers were sampled weekly and chemically analyzed. Percent loss of TML, the male lure for Ceratitis capitata (Wiedemann) Mediterranean fruit fly; ME, the male lure for Bactrocera dorsalis (Hendel), oriental fruit fly; RK, the male lure for Bactrocera cucurbitae (Coquillett), melon fly; and DDVP was measured. Based on regression analyses for the male lures, TML degraded the fastest followed by ME. Degradation of the more chemically stable RK was discontinuous, did not fit a regression model, but followed similar seasonal patterns. There were few location differences for all three male lures and DDVP. Dispensers degraded faster during summer than winter. An asymptotic regression model provided a good fit for % loss (ME, TML, and DDVP) for summer data. Degradation of DDVP in TMR dispensers was similar to degradation of DDVP in insecticidal strips. Based on these chemical analyses and prior bioassay results with wild flies, TMR dispensers could potentially be used in place of three individual male lure traps, reducing costs of fruit fly survey programs. Use of an insecticidal tape would not require TMR dispensers without DDVP to be registered with US-EPA.

Docosahexaenoic acid (DHA) is a major constituent, and primary omega-3 fatty acid, in the brain. Evidence suggests that DHA consumption may promote cognitive functioning and prevent cognitive decline, and these effects may be particularly relevant in the context of fear or stress. However, the potency and efficacy of dietary DHA may depend on the form of DHA (e.g., phospholipid; PL vs. triglyceride; TG). In this study, we compared in mice the effects of consuming PL and TG forms of DHA on associative, avoidance (fear) based learning and memory. Diets consisted of either no DHA or 1%, 2%, and 4% PL- or TG-DHA. After 4 weeks on the test diets (n = 12/group), we used the 3-day passive avoidance (PA) and elevated plus maze (EPM) to examine fear and fear-associated learning and memory. We found a significant (p < 0.05) diet by time interaction in the PA and EPM. Compared to the control and the 1% TG-DHA group, mice consuming the diet supplemented with 1% PL-DHA displayed a significantly greater latency by test day 2 in the 3-day PA. No differences in latency between any of the groups were observed during trials 1 and 3. Mice consuming the 2% PL-DHA diet spent significantly more time frequenting the open arms during the first minute, but not the last 4 min, of the test. Compared to all other groups, mice fed the 4% TG-DHA diet had increased spleen, liver, and visceral fat weight. Consumption of the lower dose PL-DHA may confer enhanced efficacy, particularly on fear-based learning behavior.

Core Ideas Interest in the use of active optical sensors for guiding N fertilizer management of crops like wheat has grown rapidly since the mid‐1990s. Recently, active optical sensors have been used to assess water status of crops in addition to plant N status. We conducted a 2‐yr study on a Casa Grande sandy loam soil in Maricopa, AZ, with durum wheat under an overhead sprinkler system. Uniquely, this study had 10 unrandomized levels of irrigation and five rates of N fertilizer. The objectives were to compare 12 vegetation indices for their ability to distinguish irrigation and N fertilizer rates and to determine how well the vegetation indices estimated biomass, plant N, grain yield, grain N, and yellow berry. The canopy chlorophyll content index, Datt, and Meris terrestrial chlorophyll index were the most consistent vegetation indices in responding well to N, with minimal water effects. No vegetation indices detected water stress with minimal N effect as well as canopy temperature measured with infrared thermometers. Interest in active optical sensors (AOS) for guiding N fertilizer management of crops like wheat ( Triticum aestivum L.) has grown rapidly since their introduction in the mid‐1990s. Recently, AOS have been used to assess water status of crops in addition to plant N status. Specific vegetation indices (VIs) might assess N stress while minimizing effects of water stress. A 2‐yr study (2013–2014) was conducted on a Casa Grande sandy loam soil in Maricopa, AZ, with durum wheat ( T. durum Desf) under an overhead sprinkler system. Uniquely, this study had 10 unrandomized levels of irrigation and five rates of N fertilizer. The objectives were to compare 12 VIs for their ability to distinguish irrigation and N fertilizer effects and to determine how well the VIs estimated biomass, plant N, grain yield, grain N, and yellow berry (opaque starchy grain). Two Crop Circle 470 AOS were passed at a fixed height, 1 m above the tallest plants in the field, every 7 to 10 d during the growing season. The normalize difference vegetation indices (NDVIs) showed highly significant response to N rate in three of four growth‐stage‐years, but significant water and small N effects at Zadoks 32 (early stem elongation) in 2014. The canopy chlorophyll content index (CCCI), DATT (Datt, 1999), and Meris terrestrial chlorophyll index (MTCI) were the most consistent VIs in distinguishing N rates, with minimal water effects. No VIs detected water stress with minimal N effect as well as the infrared thermometer (IRT) measurements of canopy temperature did.

Invasion by the exotic annual grass Bromus tectorum often increases soil nutrient availability. It is unclear, however, if other grasses benefit from this higher nutrient status. Soil from three sites in the northern Great Basin U.S.A. conditioned by B. tectorum invasion (BTCS=B. tectorum conditioned soil), paired with adjacent areas conditioned by native vegetation (NCS=native conditioned soil), were freshly-collected. Replicates were sown to B. tectorum, Elymus wawawaiensis (native perennial grass), and Agropyron cristatum (exotic perennial grass) and grown for 70 days. Above-ground biomass of the exotics B. tectorum and A. cristatum averaged over 2 times greater in BTCS relative to their growth in NCS. Above-ground biomass of the native E. wawawaiensis was statistically similar whether grown in BTCS or NCS. Overall, plants grown in BTCS had statistically similar tissue N and significantly greater tissue P concentrations compared to plants grown in NCS. The native perennial grass had significantly more negative ∂15N values when grown in BTCS relative to NCS suggesting it is accessing isotopically different N sources between the two substrates that B. tectorum or A. cristatum do not sense. Post-harvest soil mineral N was significantly greater for BTCS compared with NCS. Grown in BTCS, both exotic grasses significantly reduced soil mineral N relative to unplanted controls, but the native grass did not. The variable with the strongest explanatory power for above-ground plant mass was % utilization of the pre-plant soil pool of bicarbonate-extractable P. For the two exotics tested, BTCS is a superior growth medium than NCS. The native E. wawawaiensis may not benefit from growth in BTCS because it has slower nutrient uptake kinetics and growth to efficiently utilize greater N and P availability.